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This study investigates the transport of particles in turbulent channel flow with friction Reynolds number $Re_\tau = 1000$ by direct numerical simulation. We focus on how large-scale flow structures, namely the $Qs$ structures (Lozano-Durán et al. 2012, J. Fluid Mech., vol. 694, pp. 100–130), affect the wall-normal transport of particles. Despite occupying less than $10\,\%$ of the physical domain, our results highlight the critical role played by $Qs$ structures in the particle transport, namely that the particle number and momentum flux inside the $Qs$ structures are substantially higher than outside. The fraction of particle wall-normal momentum flux inside $Qs$ structures is considerably larger than their volume fraction, suggesting highly efficient transport inside the $Qs$ structures. This prominent role played by $Qs$ structures in the transport of inertial particles is more effective by diminishing the inertia of particles. Notably, the long-distance transport of particles in the wall-normal direction is driven primarily by the continuous effect of $Qs$ structures. In summary, our findings advance the understanding of the effects of $Qs$ structures on particle transport, and demonstrate their significant role in the process.
The extracellular matrices, such as the haemolymph, in insects are at the centre of most physiological processes and are protected from oxidative stress by the extracellular antioxidant enzymes. In this study, we identified two secreted superoxide dismutase genes (PxSOD3 and PxSOD5) and investigated the oxidative stress induced by chlorpyrifos (CPF) in the aquatic insect Protohermes xanthodes (Megaloptera: Corydalidae). PxSOD3 and PxSOD5 contain the signal peptides at the N-terminus. Structure analysis revealed that PxSOD3 and PxSOD5 contain the conserved CuZn-SOD domain, which is mainly composed of β-sheets and has conserved copper and zinc binding sites. Both PxSOD3 and PxSOD5 are predicted to be soluble proteins located in the extracellular space. After exposure to different concentrations of sublethal CPF, MDA content in P. xanthodes larvae were increased in a dose-dependent manner; SOD and CAT activities were also higher in CPF-treated groups than that in the no CPF control, indicating that sublethal CPF induces oxidative stress in P. xanthodes larvae. Furthermore, PxSOD3 and PxSOD5 expression levels and haemolymph SOD activity in the larvae were downregulated by sublethal CPF at different concentrations. Our results suggest that the PxSOD3 and PxSOD5 are putative extracellular antioxidant enzymes that may play a role in maintaining the oxidative balance in the extracellular space. Sublethal CPF may induce oxidative stress in the extracellular space of P. xanthodes by reducing the gene expression and catalytic activity of extracellular SODs.
This study aimed to investigate the relationship between serum folate levels and the risk of psoriasis by integrating observational study with Mendelian Randomisation (MR) analysis. We firstly conducted an observational study using data from the National Health and Nutrition Examination Survey (NHANES). Subsequently, genetic instruments were selected for two-sample MR analyses to investigate the causal relationship between serum folate levels and the risk of psoriasis. The observational study showed no significant association between serum folate levels and psoriasis. In the fully adjusted model, neither serum folate level as a continuous variable (OR = 0·99, 95 % CI: 0·98, 1·00, P = 0·071) nor serum folate quartiles Q4 compared to Q1 (OR = 0·83, 95 % CI: 0·58, 1·19, P = 0·309) showed statistical significance. The MR analysis revealed that higher genetically predicted serum folate levels from Icelandic and Danish populations were significantly associated with a reduced risk of psoriasis (OR = 0·63, 95 % CI: 0·45, 0·88, P = 0·005). Similarly, higher genetically predicted serum folate levels from South Asian populations were significantly associated with a lower risk of psoriasis (OR = 0·84, 95 % CI: 0·72, 0·98, P = 0·025). Integrating observational study with MR analysis suggests that serum folate levels are protective factors against psoriasis, indicating that higher serum folate levels may help prevent the onset of the disease.
This paper provides an overview of the current status of ultrafast and ultra-intense lasers with peak powers exceeding 100 TW and examines the research activities in high-energy-density physics within China. Currently, 10 high-intensity lasers with powers over 100 TW are operational, and about 10 additional lasers are being constructed at various institutes and universities. These facilities operate either independently or are combined with one another, thereby offering substantial support for both Chinese and international research and development efforts in high-energy-density physics.
When a droplet impacts onto a superheated liquid pool, vapour generation and drainage within the gas cushion play a crucial role in postponing or even preventing contact between the droplet and the pool surface. Through direct numerical simulations, we closely examine the transient dynamics of vapour flow confined within the thin film, with a particular focus on the minimum thickness of this film under a range of impact conditions. Our numerical findings manifest the significant influence of evaporation on the vertical motion of the liquid–vapour interface, revealing how the minimum film thickness evolves in response to variations in impact velocity and degree of superheat. In our numerical simulations, we have identified two distinct evolution laws for the minimum film thickness, corresponding to moderate and high superheat regimes, respectively. These regimes are differentiated by the dominance of evaporation effects within the vapour film during the early falling stage. Subsequently, we establish scaling relations to characterize these regimes by carefully balancing inertial, pressure and evaporation effects within the thin vapour film. Furthermore, we observe that the vapour pressure eventually reaches equilibrium with the rapid increase in capillary pressure at the spreading front, thereby controlling the minimum thickness of the vapour layer in both moderate and high superheat regimes. We derive self-similar solutions based on this equilibrium, and the predicted minimum film thickness aligns remarkably well with our numerical results. This provides compelling evidence that evaporation alone is insufficient to prevent droplet–pool coalescence.
Stimulated Raman scattering is a third-order nonlinear optical effect that is not only effective for wavelength converting laser output, but also for single longitudinal-mode output due to the absence of spatial hole burning. Diamond is a prominent Raman-active medium that has significant potential for linewidth narrowing and wavelength converting lasers at high power levels due to its high thermal conductivity, long Raman frequency shift and wide spectral transmission range. In this work we utilize diamond in a resonantly mode-matched external cavity to achieve cascaded Raman conversion of a 1064 nm laser. By fine-tuning the length of this external cavity, we can obtain narrow linewidth emission at 1240 and 1485 nm. When operating at maximum power, the measured linewidths were more than twofold narrower than the linewidth of the fundamental field. In addition, the noise levels of the Stokes fields are lower than that of the fundamental field throughout the entire noise frequency range, and the intrinsic linewidth of the second Stokes field, which is expressed at the hertz level (~3.6 Hz), is decreased by approximately three orders of magnitude compared to that of the pump. This work represents the first measurement and analysis of the linewidth and noise characteristics of cascaded diamond Raman lasers and, significantly, offers a new means by which high-power, narrow linewidth laser output can be produced from wavelength-converted laser systems.
An optical spectrometer system based on 60 channels of fibers has been designed and employed to diagnose light emissions from laser–plasma interactions. The 60 fiber collectors cover an integrated solid angle of $\pi$, enabling the measurement of global energy losses in a symmetrical configuration. A detecting spectral range from ultraviolet to near-infrared, with angular distribution, allows for the understanding of the physical mechanisms involving various plasma modes. Experimental measurements of scattered lights from a conical implosion driven by high-energy nanosecond laser beams at the Shenguang-II Upgrade facility have been demonstrated, serving as reliable diagnostics to characterize laser absorption and energy losses from laser–plasma instabilities. This compact diagnostic system can provide comprehensive insights into laser energy coupling in direct-drive inertial confinement fusion research, which are essential for studying the driving asymmetry and improving the implosion efficiencies.
Dietary restriction-influenced biological performance is found in many animal species. Pardosa pseudoannulata is a dominant spider species in agricultural fields and is important for controlling pests. In this study, three groups – a control group (CK group), a re-feeding group (RF group), and a dietary restriction group (RT group) – were used to explore development, mating, reproduction, and the expression levels of Vg (vitellogenin) and VgR (vitellogenin receptor) genes in the spider. The findings indicated that when subjected to dietary restriction, the carapace size, weight of the spiderlings, and weight of the adults exhibited a decrease. Furthermore, the preoviposition period and egg stage were observed to be prolonged, while the number of spiderlings decreased. It was also observed that re-feeding reduced cannibalism rates and extended the preoviposition period. Dietary restriction also affected the expression of the Vg-3 gene in the spider. These results will contribute to the understanding of the impact of dietary restriction in predators of pest control, as well as provide a theoretical foundation for the artificial rearing and utilisation of the dominant spider in the field.
Panax L., renowned as ginseng genus, is a famous medicinal group of family Araliaceae. Within this genus, the taxa of Panax bipinnatifidus complex are mainly distributed in Himalayas and Hengduan Mountain areas. Due to the complex evolutionary history and short-term rapid radiation, the relationships among species within the complex have not been clearly resolved, and the taxa identification is difficult due to the intermediate morphological traits. This study aimed to use the available restriction-site associated DNA sequence data from 29 individuals of P. bipinnatifidus complex to mine high-polymorphic simple sequence repeat (SSR) markers, with the goal of evaluating their utility in taxa identification. Eleven polymorphic SSR loci were ultimately selected and validated through polymerase chain reactions amplifying across 63 individuals of P. bipinnatifidus complex and 13 individuals of three outgroup species. The subsequent genetic diversity analysis uncovered 76 alleles in total, ranging from 5 to 15 per locus. Observed heterozygosity spanned 0.241–0.512, while expected heterozygosity ranged between 0.345 and 0.644. The genetic kinship analysis revealed a sister relationship between Panax zingiberensis and Panax vietnamensis. The analysis result also supported the classification of samples from Hunan and Hubei provinces into a single genetic unit within the P. bipinnatifidus complex. These newly developed SSR markers will facilitate the identification of wild ginseng plants.
The discovery that blazars dominate the extra-galactic $\gamma$-ray sky is a triumph in the Fermi era. However, the exact location of $\gamma$-ray emission region still remains in debate. Low-synchrotron-peaked blazars (LSPs) are estimated to produce high-energy radiation through the external Compton process, thus their emission regions are closely related to the external photon fields. We employed the seed factor approach proposed by Georganopoulos et al. It directly matches the observed seed factor of each LSP with the characteristic seed factors of external photon fields to locate the $\gamma$-ray emission region. A sample of 1 138 LSPs with peak frequencies and peak luminosities was adopted to plot a histogram distribution of observed seed factors. We also collected some spectral energy distributions (SEDs) of historical flare states to investigate the variation of $\gamma$-ray emission region. Those SEDs were fitted by both quadratic and cubic functions using the Markov-chain Monte Carlo method. Furthermore, we derived some physical parameters of blazars and compared them with the constraint of internal $\gamma\gamma$-absorption. We find that dusty torus dominates the soft photon fields of LSPs and most $\gamma$-ray emission regions of LSPs are located at 1–10 pc. The soft photon fields could also transition from dusty torus to broad line region and cosmic microwave background in different flare states. Our results suggest that the cubic function is better than the quadratic function to fit the SEDs.
MicroRNAs (miRNAs) are endogenous, non-coding RNAs, which are functional in a variety of biological processes through post-transcriptional regulation of gene expression. However, the role of miRNAs in the interaction between Bacillus thuringiensis and insects remains unclear. In this study, small RNA libraries were constructed for B. thuringiensis-infected (Bt) and uninfected (CK) Spodoptera exigua larvae (treated with double-distilled water) using Illumina sequencing. Utilising the miRDeep2 and Randfold, a total of 233 known and 726 novel miRNAs were identified, among which 16 up-regulated and 34 down-regulated differentially expressed (DE) miRNAs were identified compared to the CK. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that potential target genes of DE miRNAs were associated with ABC transporters, fatty acid metabolism and MAPK signalling pathway which are related to the development, reproduction and immunity. Moreover, two miRNA core genes, SeDicer1 and SeAgo1 were identified. The phylogenetic tree showed that lepidopteran Dicer1 clustered into one branch, with SeDicer1 in the position closest to Spodoptera litura Dicer1. A similar phylogenetic relationship was observed in the Ago1 protein. Expression of SeDicer1 increased at 72 h post infection (hpi) with B. thuringiensis; however, expression of SeDicer1 and SeAgo1 decreased at 96 hpi. The RNAi results showed that the knockdown of SeDicer1 directly caused the down-regulation of miRNAs and promoted the mortality of S. exigua infected by B. thuringiensis GS57. In conclusion, our study is crucial to understand the relationship between miRNAs and various biological processes caused by B. thuringiensis infection, and develop an integrated pest management strategy for S. exigua via miRNAs.
Accurate online estimation of the payload parameters benefits robot control. In the existing approaches, however, on the one hand, only the linear friction model was used for online payload identification, which reduced the online estimation accuracy. On the other hand, the estimation models contain much noise because of using actual joint trajectory signals. In this article, a new estimation algorithm based on parameter difference for the payload dynamics is proposed. This method uses a nonlinear friction model for the online payload estimation instead of the traditionally linear one. In addition, it considers the commanded joint trajectory signals as the computation input to reduce the model noise. The main contribution of this article is to derive a symbolic relationship between the parameter difference and the payload parameters and then apply it to the online payload estimation. The robot base parameters without payload were identified offline and regarded as the prior information. The one with payload can be solved online by the recursive least squares method. The dynamics of the payload can be then solved online based on the numerical difference of the two parameter sets. Finally, experimental comparisons and a manual guidance application experiment are shown. The results confirm that our algorithm can improve the online payload estimation accuracy (especially the payload mass) and the manual guidance comfort.
Path planning for the unmanned aerial vehicle (UAV) is to assist in finding the proper path, serving as a critical role in the intelligence of a UAV. In this paper, a path planning for UAV in three-dimensional environment (3D) based on enhanced gravitational search algorithm (EGSA) is put forward, taking the path length, yaw angle, pitch angle, and flight altitude as considerations of the path. Considering EGSA is easy to fall into local optimum and convergence insufficiency, two factors that are the memory of current optimal and random disturbance with chaotic levy flight are adopted during the update of particle velocity, improving the balance between exploration and exploitation for EGSA through different time-varying characteristics. With the identical cost function, EGSA is compared with seven peer algorithms, such as moth flame optimization algorithm, gravitational search algorithm, and five variants of gravitational search algorithm. The experimental results demonstrate that EGSA is superior to the seven comparison algorithms on CEC 2020 benchmark functions and the path planning method based on EGSA is more valuable than the other seven methods in diverse environments.
Caused by multiple risk factors, heavy burden of major depressive disorder (MDD) poses serious challenges to public health worldwide over the past 30 years. Yet the burden and attributable risk factors of MDD were not systematically known. We aimed to reveal the long-term spatio-temporal trends in the burden and attributable risk factors of MDD at global, regional and national levels during 1990–2019.
Methods
We obtained MDD and attributable risk factors data from Global Burden of Disease Study 2019. We used joinpoint regression model to assess the temporal trend in MDD burden, and age–period–cohort model to measure the effects of age, period and birth cohort on MDD incidence rate. We utilized population attributable fractions (PAFs) to estimate the specific proportions of MDD burden attributed to given risk factors.
Results
During 1990–2019, the global number of MDD incident cases, prevalent cases and disability-adjusted life years (DALYs) increased by 59.10%, 59.57% and 58.57%, respectively. Whereas the global age-standardized incidence rate (ASIR), age-standardized prevalence rate (ASPR) and age-standardized DALYs rate (ASDR) of MDD decreased during 1990–2019. The ASIR, ASPR and ASDR in women were 1.62, 1.62 and 1.60 times as that in men in 2019, respectively. The highest age-specific incidence, prevalence and DALYs rate occurred at the age of 60–64 in women, and at the age of 75–84 in men, but the maximum increasing trends in these age-specific rates occurred at the age of 5–9. Population living during 2000–2004 had higher risk of MDD. MDD burden varied by socio-demographic index (SDI), regions and nations. In 2019, low-SDI region, Central sub-Saharan Africa and Uganda had the highest ASIR, ASPR and ASDR. The global PAFs of intimate partner violence (IPV), childhood sexual abuse (CSA) and bullying victimization (BV) were 8.43%, 5.46% and 4.86% in 2019, respectively.
Conclusions
Over the past 30 years, the global ASIR, ASPR and ASDR of MDD had decreased trends, while the burden of MDD was still serious, and multiple disparities in MDD burden remarkably existed. Women, elderly and populations living during 2000–2004 and in low-SDI regions, had more severe burden of MDD. Children were more susceptible to MDD. Up to 18.75% of global MDD burden would be eliminated through early preventing against IPV, CSA and BV. Tailored strategies-and-measures in different regions and demographic groups based on findings in this studywould be urgently needed to eliminate the impacts of modifiable risk factors on MDD, and then mitigate the burden of MDD.
The purpose of this experiment was to evaluate the contribution of epiphytic microbiota on alfalfa (AL), oat (OT), and red clover (RC) to ensiling characteristics and bacterial community diversity of oat. With the irradiation of γ-ray, sterile OT (~233 g/kg dry matter (DM)) was inoculated by sterile water (STOT), epiphytic microbiota from OT (OTOT), AL (OTAL) and RC (OTRC), respectively. Triplicate silage-bags for each treatment were sampled after different days (1, 3, 7, 15, 30 and 60) of fermentation, respectively. Similar chemical compositions were found between fresh oat and STOT. Lower (P < 0.05) contents of ammonia nitrogen (NH3-N) and higher (P < 0.05) accumulation of lactic acid were found in OTAL compared with OTRC and OTOT on day 3. The greatest (P < 0.05) NH3-N, acetic acid concentrations and pH and the lowest (P < 0.05) concentration of lactic acid were found in OTRC on day 60. After 3 days of ensiling, Lactobacillus accounted for a big proportion in OTAL and OTOT, and Hafnia-Obesumbacterium was predominant in OTRC. The bacterial communities in OTAL and OTOT had lower (P < 0.05) abundances of ‘Genetic Information Processing’ than OTRC after 3 days. Overall, the composition, diversity, and activity of epiphytic microbiota can notably influence the ensiling characteristics of forage oat. The lactic acid bacteria (hetero-fermentative type) and Enterobacteriaceae species played an important role in producing ethanol contents during the ensiling of forage oat.
Double-cone ignition [Zhang et al., Phil. Trans. R. Soc. A 378, 20200015 (2020)] was proposed recently as a novel path for direct-drive inertial confinement fusion using high-power lasers. In this scheme, plasma jets with both high density and high velocity are required for collisions. Here we report preliminary experimental results obtained at the Shenguang-II upgrade laser facility, employing a CHCl shell in a gold cone irradiated with a two-ramp laser pulse. The CHCl shell was pre-compressed by the first laser ramp to a density of 3.75 g/cm3 along the isentropic path. Subsequently, the target was further compressed and accelerated by the second laser ramp in the cone. According to the simulations, the plasma jet reached a density of up to 15 g/cm3, while measurements indicated a velocity of 126.8 ± 17.1 km/s. The good agreements between experimental data and simulations are documented.
OBJECTIVES/GOALS: Incomplete mucosal healingand dysbiosis prevent long-term remission after colitis. IL4 may restore colon homeostasis through its action on immune cells and the microbiome. We will demonstrate this mechanism using genetically modified mice and molecular tools. This may result in target therapies that prolong remission in patients with IBD. METHODS/STUDY POPULATION: Mice were treated with 3% dextran sulfate sodium (DSS) in drinking water for 5 days to induce colitis. Mice were monitored daily for changes in body weight, and to monitor colitis severity. At each endpoint, mice were sacrificed and colon length was measured. For disease severity assessment, mouse colons were prepared in paraffin sections by the 'swiss-rolling' method. For flow cytometry, lamina propria mononuclear cell isolation was performed and cellular populations were stained with fluorophore-conjugated antibodies. IL4-eGFP-expressing (4get) mice were used to analyze the cellular expression of IL4 after colitis. Cell-specific IL4 deletion mice were generated using the cre-lox system. RESULTS/ANTICIPATED RESULTS: IL4-deficient mice had worse colitis compared with wild-type controls. Flow cytometry of lamina propria cells from 4get mice showed that most IL4-producing cells after colitis are eosinophils (CD11b+SiglecF+). Flow cytometry of C57bl6 mice showed an influx of IL4Ra+ monocytes (CD11b+Ly6C+) and macrophages (CD11b+F480+). IL4-stimulated bone marrow-derived macrophages demonstrated an increase in HB-EGF mRNA transcription. Myeloid-specific IL4R deleted mice had no difference in colitis severity compared with controls. Neutrophil-specific IL4R-deleted mice had increased colitis severity and mortality. Co-housing of littermate mice rescued recovery after DSS in IL4 deficient mice. DISCUSSION/SIGNIFICANCE: IL4 appears to play a role in restoring homeostasis after colitis. The mechanism depends on eosinophil-derived IL4, and action through neutrophils. However, the reparative function of IL4 can be shared with deficient mice through the microbiome. I will study the cellular and microbial mechanism by which IL4 restores homeostasis after colitis.
Lymph node tuberculosis is particularly common in regions with a high tuberculosis burden, and it has a great risk of rupture. This study aims to investigate the utility of ultrasound multimodal imaging in predicting the rupture of cervical tuberculous lymphadenitis (CTL). 128 patients with unruptured CTL confirmed by pathology or laboratory tests were included. Various ultrasonic image features, including long-to-short-axis ratio (L/S), margin, internal echotexture, coarse calcification, Color Doppler Flow Imaging (CDFI), perinodal echogenicity, elastography score, and non-enhanced area proportion in contrast-enhanced ultrasound (CEUS), were analyzed to determine their predictive value for CTL rupture within a one-year follow-up period. As a result, L/S (P < 0.001), margin (P < 0.001), internal echotexture (P < 0.001), coarse calcification (P < 0.001), perinodal echogenicity (P < 0.001), and the area of non-enhancement in CEUS (P < 0.001) were identified as significant imaging features for predicting CTL rupture. The prognostic prediction showed a sensitivity of 89.29%, specificity of 100%, accuracy of 95.31%, respectively. Imaging findings such as L/S < 2, unclear margin, heterogeneous internal echotexture, perinodal echogenicity changed, and non-enhancement area in CEUS > 1/2, are indicative of CTL rupture, while coarse calcification in the lymph nodes is associated with a favorable prognosis.
In preparation for an experiment with a laser-generated intense proton beam at the Laser Fusion Research Center at Mianyang to investigate the 11B(p,α)2α reaction, we performed a measurement at very low proton energy between 140 keV and 172 keV using the high-voltage platform at the Institute of Modern Physics, Lanzhou. The aim of the experiment was to test the ability to use CR-39 track detectors for cross-section measurements and to remeasure the cross-section of this reaction close to the first resonance using the thick target approach. We obtained the cross-section σ = 45.6 ± 12.5 mb near 156 keV. Our result confirms the feasibility of CR-39 type track detector for nuclear reaction measurement also in low-energy regions.