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A novel entomopathogenic nematode (EPN) species, Steinernema tarimense n. sp., was isolated from soil samples collected in a Populus euphratica forest located in Yuli County within the Tarim Basin of Xinjiang, China. Integrated morphological and molecular analyses consistently place S. tarimense n. sp. within the ‘kushidai-clade’. The infective juvenile (IJ) of new species is characterized by a body length of 674–1010 μm, excretory pore located 53–80 μm from anterior end, nerve ring positioned 85–131 μm from anterior end, pharynx base situated 111–162 μm from anterior end, a tail length of 41–56 μm, and the ratios D% = 42.0–66.6, E% = 116.2–184.4, and H% = 25.5–45.1. The first-generation male of the new species is characterized by a curved spicule length of 61–89 μm, gubernaculum length of 41–58 μm, and ratios D% = 36.8–66.2, SW% = 117.0–206.1, and GS% = 54.8–82.0. Additionally, the tail of first-generation female is conoid with a minute mucron. Phylogenetic analyses of ITS, 28S, and mt12S sequences demonstrated that the three isolates of S. tarimense n. sp. are conspecific and form a sister clade to members of the ‘kushidai-clade’ including S. akhursti, S. anantnagense, S. kushidai, and S. populi. Notably, the IJs of the new species exhibited faster development at 25°C compared to other Steinernema species. This represents the first described of an indigenous EPN species from Xinjiang, suggesting its potential as a novel biocontrol agent against local pests.
In this paper, we investigate the attitude manoeuver planning and tracking control of the flexible satellite equipped with a coilable mast. Due to its flexible beamlike structure, the coilable mast experiences bending and torsional modal vibrations in multi-direction. The complex nonlinear coupling and other external disturbances significantly impact the achievement of high-precision attitude control. To overcome these challenges, a robust attitude tracking controller is proposed for easy implementation by the Attitude Determination and Control System (ADCS). The controller consists of a disturbance compensator, feedforward controller and output feedback controller. The compensator, based on a Nonlinear Disturbance Observer (NDO), effectively compensates for the cluster disturbances caused by vibrations, environmental factors and parameter perturbations. The feedforward controller tracks the desired path in the nominal satellite model. Furthermore, the output feedback controller enables large-angle manoeuver control of the satellite and evaluates the suppression effect of the controlled output on the observation error of cluster disturbances used the ${L_2}$-gain. Simulation results demonstrate that the proposed controller successfully achieves high-precision attitude tracking control during large-angle manoeuvering.
This paper proposes a fixed-time anti-saturation (FT-AS) control scheme with a simple control loop for the 6-Degree-of-Freedom tracking (6-DOF) control problem of spacecraft with parameter uncertainties, external disturbances and input saturation. Considering the external disturbance and parameter uncertainties, the dynamical model of the tracking error is established. The traditional methods of handling input saturation usually add anti-saturation subsystems in the control system to suppress the impact of input overshoot. However, this paper directly inputs the input overshoot into the tracking error model, thus constructing a modified lumped disturbance term that includes the influence of input overshoot. Then, a novel fixed-time disturbance observer (FT-DO) is designed to estimate and compensate for this modified lumped disturbance. Therefore, there is no need to add the anti-saturation structures in the control loop, significantly reducing the complexity of the system. Finally, an observer-based fixed-time non-singular terminal sliding mode (FT-NTSM) controller is designed to guarantee the fixed-time stability of the whole system. In this way, the convergence time of the proposed scheme does not depend on the system’s initial conditions. Simulation results illustrate that the proposed method keeps the control input within the limit while achieving high-precision tracking control of attitude and position.
Competition among the two-plasmon decay (TPD) of backscattered light of stimulated Raman scattering (SRS), filamentation of the electron-plasma wave (EPW) and forward side SRS is investigated by two-dimensional particle-in-cell simulations. Our previous work [K. Q. Pan et al., Nucl. Fusion 58, 096035 (2018)] showed that in a plasma with the density near 1/10 of the critical density, the backscattered light would excite the TPD, which results in suppression of the backward SRS. However, this work further shows that when the laser intensity is so high ($>{10}^{16}$ W/cm2) that the backward SRS cannot be totally suppressed, filamentation of the EPW and forward side SRS will be excited. Then the TPD of the backscattered light only occurs in the early stage and is suppressed in the latter stage. Electron distribution functions further show that trapped-particle-modulation instability should be responsible for filamentation of the EPW. This research can promote the understanding of hot-electron generation and SRS saturation in inertial confinement fusion experiments.
The target backsheath field acceleration mechanism is one of the main mechanisms of laser-driven proton acceleration (LDPA) and strongly depends on the comprehensive performance of the ultrashort ultra-intense lasers used as the driving sources. The successful use of the SG-II Peta-watt (SG-II PW) laser facility for LDPA and its applications in radiographic diagnoses have been manifested by the good performance of the SG-II PW facility. Recently, the SG-II PW laser facility has undergone extensive maintenance and a comprehensive technical upgrade in terms of the seed source, laser contrast and terminal focus. LDPA experiments were performed using the maintained SG-II PW laser beam, and the highest cutoff energy of the proton beam was obviously increased. Accordingly, a double-film target structure was used, and the maximum cutoff energy of the proton beam was up to 70 MeV. These results demonstrate that the comprehensive performance of the SG-II PW laser facility was improved significantly.
Collaborative planning for multiple hypersonic vehicles can effectively improve operational effectiveness. Time coordination is one of the main forms of cooperation among multi-hypersonic glide vehicles, and time cooperation trajectory optimisation is a key technology that can significantly increase the success rate of flight missions. However, it is difficult to obtain satisfactory time as a constraint condition during trajectory optimisation. To solve this problem, a multilayer Perceptrona is trained and adopted in a time-decision module, whose input is a four-dimensional vector selected according to the trajectory characteristics. Additionally, the MLP will be capable of determining the optimal initial heading angle of each aircraft to reduce unnecessary manoeuvering performance consumption in the flight mission. Subsequently, to improve the cooperative flight performance of hypersonic glide vehicles, the speed-dependent angle-of-attack and bank command were designed and optimised using the Artificial Bee Colony algorithm. The final simulation results show that the novel strategy proposed in this study can satisfy terminal space constraints and collaborative time constraints simultaneously. Meanwhile, each aircraft saves an average of 13.08% flight range, and the terminal speed is increased by 315.6m/s compared to the optimisation results of general purpose optimal control software (GPOPS) tools.
OBJECTIVES/GOALS: NSF often requires cross-disciplinary team composition to be competitive for funding. To what extent do research teams have multidisciplinary authorships after they win an award, given that awards are not contracts? We examined the quantity and quality of multidisciplinary collaboration of NSF-funded teams before and after receiving their award. METHODS/STUDY POPULATION: Our sample was 150 PIs and Co-PIs (67% male) from 58 NSF-funded EAGER (EArly-concept Grants for Exploratory Research) grants between 2013 and 2019. Using publicly available information, we collected the number of conference papers, publications, and grants PIs/co-PIs produced with each other (all PIs and co-PIs in a team or a partial subset). Based on Ph.D. fields, we also cataloged whether the combination of PIs/co-PI authors on outputs represented unidisciplinary or multidisciplinary collaboration after their NSF award. Multidisciplinary collaboration consisted of multidivisional (Ph.D. disciplines across NSF divisions, e.g., political science and cognitive psychology) or multidirectorate (Ph.D. disciplines across NSF directorates, e.g., psychology and engineering) authorship. RESULTS/ANTICIPATED RESULTS: Of the 74% of PI and co-PI teams who collaborated after their EAGER award, almost 9 out of 10 chose to work with a collaborator from a different discipline, and almost 8 out of 10 chose to work with a researcher from an extremely diverse discipline from their own (e.g., computer science and psychology). Research on interdisciplinary teams largely emphasizes the challenges and problems they face but the current research demonstrated that 90% of the sample chose to continue working together across disciplines after EAGER awards. Therefore, future research should dedicate more attention to the nontangible benefits members receive in interdisciplinary teams. Moreover, quality measures revealed higher H-indices for multidisciplinary than unidisciplinary journals and conferences. DISCUSSION/SIGNIFICANCE: Our archival results revealed that NSF EAGER grants are having their intended effect of being a catalyst for 1) continued multidisciplinary (and especially multidirectorate) collaboration) and 2) high-quality multidisciplinary publication and conference output. These results have contributed to NSF policy changes to reinstate the EAGER grant.
As a typical plasma-based optical element that can sustain ultra-high light intensity, plasma density gratings driven by intense laser pulses have been extensively studied for wide applications. Here, we show that the plasma density grating driven by two intersecting driver laser pulses is not only nonuniform in space but also varies over time. Consequently, the probe laser pulse that passes through such a dynamic plasma density grating will be depolarized, that is, its polarization becomes spatially and temporally variable. More importantly, the laser depolarization may spontaneously take place for crossed laser beams if their polarization angles are arranged properly. The laser depolarization by a dynamic plasma density grating may find application in mitigating parametric instabilities in laser-driven inertial confinement fusion.
This study aimed to investigate the relationship between bone quality in terms of metabolism, homeostasis of elements, bone mineral density (BMD), and microstructure and keel-bone fractures in laying hens (Gallus gallus domesticus). One hundred and twenty 17 week old Lohmann White laying hens with normal keel bones were individually housed in furnished cages for 25 weeks. Birds were then euthanased and dissected to assess keel-bone status at 42 weeks. Serum and keel-bone samples from normal keel (NK) and fractured keel (FK) hens were collected to determine the previously mentioned bone quality parameters. The results showed FK hens to have higher levels of the components of osteocalcin, greater alkaline phosphatase activity in serum and keel bones, and greater tartrate-resistant acid phosphatase (TRAP) activity in keel bones, compared to NK hens. Additionally, FK hens also had higher concentrations of Li, B, K, Cu, As, Se, Sn, Hg, and Pb, but lower concentrations of Na, P, and Ca. Moreover, FK hens showed decreased bone microstructural parameters including bone volume/tissue volume, trabecular number, degree of anisotropy, connectivity density, and BMD, but increased trabecular separation. Meanwhile, no differences were detected in serum TRAP activity, trabecular thickness, bone surface, or bone surface/bone volume. Results showed laying hens with keel-bone fractures to have differences in bone metabolism, elements of home-ostasis, bone microstructure parameters, and BMD. These results suggest that keel-bone fractures may be associated with bone quality.
The extant findings have been of great heterogeneity due to partial volume effects in the investigation of cortical gray matter volume (GMV), high comorbidity with other psychiatric disorders, and concomitant therapy in the neuroimaging studies of social anxiety disorder (SAD).
Objectives
To identity gray matter deficits in cortical and subcortical structures in non-comorbid never-treated patients, so as to explore the “pure” SAD-specific pathophysiology and neurobiology.
Methods
Thirty-two non-comorbid free-of-treatment patients with SAD and 32 demography-matched healthy controls were recruited to undergo high-resolution 3.0-Tesla T1-weighted MRI. Cortical thickness (CT) and subcortical GMV were estimated using FreeSurfer; then the whole-brain vertex-wise analysis was performed to compare group differences in CT. Besides, differences in subcortical GMV of priori selected regions-of-interest: amygdala, hippocampus, putamen, and pallidum were compared by an analysis of covariance with age, gender, and total subcortical GMV as covariates.
Results
The SAD patients demonstrated significantly decreased CT near-symmetrically in the bilateral prefrontal cortex (Monte Carlo simulations of P < 0.05). Besides, smaller GMV in the left hippocampus and pallidum were also observed in the SAD cohort (two-sample t-test of P < 0.05).
Conclusions
For the first time, the current study investigated the structural alterations of CT and subcortical GMV in non-comorbid never-treated patients with SAD. Our findings provide preliminary evidences that structural deficits in cortical-striatal-limbic circuit may contribute to the psychopathological basis of SAD, and offer more detailed structural substrates for the involvement of such aberrant circuit in the imbalance between defective bottom-up response and top-down control to external stimuli in SAD.
We describe a new low-frequency wideband radio survey of the southern sky. Observations covering 72–231 MHz and Declinations south of $+30^\circ$ have been performed with the Murchison Widefield Array “extended” Phase II configuration over 2018–2020 and will be processed to form data products including continuum and polarisation images and mosaics, multi-frequency catalogues, transient search data, and ionospheric measurements. From a pilot field described in this work, we publish an initial data release covering 1,447$\mathrm{deg}^2$ over $4\,\mathrm{h}\leq \mathrm{RA}\leq 13\,\mathrm{h}$, $-32.7^\circ \leq \mathrm{Dec} \leq -20.7^\circ$. We process twenty frequency bands sampling 72–231 MHz, with a resolution of 2′–45′′, and produce a wideband source-finding image across 170–231 MHz with a root mean square noise of $1.27\pm0.15\,\mathrm{mJy\,beam}^{-1}$. Source-finding yields 78,967 components, of which 71,320 are fitted spectrally. The catalogue has a completeness of 98% at ${{\sim}}50\,\mathrm{mJy}$, and a reliability of 98.2% at $5\sigma$ rising to 99.7% at $7\sigma$. A catalogue is available from Vizier; images are made available via the PASA datastore, AAO Data Central, and SkyView. This is the first in a series of data releases from the GLEAM-X survey.
The great demographic pressure brings tremendous volume of beef demand. The key to solve this problem is the growth and development of Chinese cattle. In order to find molecular markers conducive to the growth and development of Chinese cattle, sequencing was used to determine the position of copy number variations (CNVs), bioinformatics analysis was used to predict the function of ZNF146 gene, real-time fluorescent quantitative polymerase chain reaction (qPCR) was used for CNV genotyping and one-way analysis of variance was used for association analysis. The results showed that there exists CNV in Chr 18: 47225201-47229600 (5.0.1 version) of ZNF146 gene through the early sequencing results in the laboratory and predicted ZNF146 gene was expressed in liver, skeletal muscle and breast cells, and was amplified or overexpressed in pancreatic cancer, which promoted the development of tumour through bioinformatics. Therefore, it is predicted that ZNF146 gene affects the proliferation of muscle cells, and then affects the growth and development of cattle. Furthermore, CNV genotyping of ZNF146 gene was three types (deletion type, normal type and duplication type) by Real-time fluorescent quantitative PCR (qPCR). The association analysis results showed that ZNF146-CNV was significantly correlated with rump length of Qinchuan cattle, hucklebone width of Jiaxian red cattle and heart girth of Yunling cattle. From the above results, ZNF146-CNV had a significant effect on growth traits, which provided an important candidate molecular marker for growth and development of Chinese cattle.
We report the experimental results of the commissioning phase in the 10 PW laser beamline of the Shanghai Superintense Ultrafast Laser Facility (SULF). The peak power reaches 2.4 PW on target without the last amplifying during the experiment. The laser energy of 72 ± 9 J is directed to a focal spot of approximately 6 μm diameter (full width at half maximum) in 30 fs pulse duration, yielding a focused peak intensity around 2.0 × 1021 W/cm2. The first laser-proton acceleration experiment is performed using plain copper and plastic targets. High-energy proton beams with maximum cut-off energy up to 62.5 MeV are achieved using copper foils at the optimum target thickness of 4 μm via target normal sheath acceleration. For plastic targets of tens of nanometers thick, the proton cut-off energy is approximately 20 MeV, showing ring-like or filamented density distributions. These experimental results reflect the capabilities of the SULF-10 PW beamline, for example, both ultrahigh intensity and relatively good beam contrast. Further optimization for these key parameters is underway, where peak laser intensities of 1022–1023 W/cm2 are anticipated to support various experiments on extreme field physics.
The performance of hypersonic vehicles in the take-off stage considerably influences their capability of accomplishing the flight tasks. This study is aimed at enhancing the take-off performance of a cruise aircraft using the improved chimp optimisation algorithm. The proposed algorithm, which uses the Sobol sequence for initial population generation and a function of the weight factors, can effectively overcome the problems of premature convergence and low accuracy of the original algorithm. In particular, the Sobol sequence aims to obtain a better fitness value in the first iteration, and the weight factor aims to accelerate the convergence speed and avoid the local optimal solution. The take-off mass model of the hypersonic vehicle is constructed considering the flight data obtained using the pseudo-spectral method in the climb phase. Simulations are performed to evaluate the algorithm performance, and the results show that the algorithm can rapidly and stably optimise the benchmark function. Compared to the original algorithm, the proposed algorithm requires 28.89% less optimisation time and yields an optimised take-off mass that is 1.72kg smaller.
To identify the clinical characteristics, treatment, and prognosis of relapsing polychondritis patients with airway involvement.
Methods
Twenty-eight patients with relapsing polychondritis, hospitalised in the First Hospital of Shanxi Medical University between April 2011 and April 2021, were retrospectively analysed.
Results
Fifty per cent of relapsing polychondritis patients with airway involvement had a lower risk of ear and ocular involvement. Relapsing polychondritis patients with airway involvement had a longer time-to-diagnosis (p < 0.001), a poorer outcome following glucocorticoid combined with immunosuppressant treatment (p = 0.004), and a higher recurrence rate than those without airway involvement (p = 0.004). The rates of positive findings on chest computed tomography and bronchoscopy in relapsing polychondritis patients with airway involvement were 88.9 per cent and 85.7 per cent, respectively. Laryngoscopy analysis showed that 66.7 per cent of relapsing polychondritis patients had varying degrees of mucosal lesions.
Conclusion
For relapsing polychondritis patients with airway involvement, drug treatment should be combined with local airway management.
We report on experimental observation of non-laminar proton acceleration modulated by a strong magnetic field in laser irradiating micrometer aluminum targets. The results illustrate the coexistence of ring-like and filamentation structures. We implement the knife edge method into the radiochromic film detector to map the accelerated beams, measuring a source size of 30–110 μm for protons of more than 5 MeV. The diagnosis reveals that the ring-like profile originates from low-energy protons far off the axis whereas the filamentation is from the near-axis high-energy protons, exhibiting non-laminar features. Particle-in-cell simulations reproduced the experimental results, showing that the short-term magnetic turbulence via Weibel instability and the long-term quasi-static annular magnetic field by the streaming electric current account for the measured beam profile. Our work provides direct mapping of laser-driven proton sources in the space-energy domain and reveals the non-laminar beam evolution at featured time scales.
The coronavirus disease 2019 (COVID-19) pandemic represents an unprecedented threat to mental health. Herein, we assessed the impact of COVID-19 on subthreshold depressive symptoms and identified potential mitigating factors.
Methods
Participants were from Depression Cohort in China (ChiCTR registry number 1900022145). Adults (n = 1722) with subthreshold depressive symptoms were enrolled between March and October 2019 in a 6-month, community-based interventional study that aimed to prevent clinical depression using psychoeducation. A total of 1506 participants completed the study in Shenzhen, China: 726 participants, who completed the study between March 2019 and January 2020 (i.e. before COVID-19), comprised the ‘wave 1’ group; 780 participants, who were enrolled before COVID-19 and completed the 6-month endpoint assessment during COVID-19, comprised ‘wave 2’. Symptoms of depression, anxiety and insomnia were assessed at baseline and endpoint (i.e. 6-month follow-up) using the Patient Health Questionnaire-9 (PHQ-9), Generalised Anxiety Disorder-7 (GAD-7) and Insomnia Severity Index (ISI), respectively. Measures of resilience and regular exercise were assessed at baseline. We compared the mental health outcomes between wave 1 and wave 2 groups. We additionally investigated how mental health outcomes changed across disparate stages of the COVID-19 pandemic in China, i.e. peak (7–13 February), post-peak (14–27 February), remission plateau (28 February−present).
Results
COVID-19 increased the risk for three mental outcomes: (1) depression (odds ratio [OR] = 1.30, 95% confidence interval [CI]: 1.04–1.62); (2) anxiety (OR = 1.47, 95% CI: 1.16–1.88) and (3) insomnia (OR = 1.37, 95% CI: 1.07–1.77). The highest proportion of probable depression and anxiety was observed post-peak, with 52.9% and 41.4%, respectively. Greater baseline resilience scores had a protective effect on the three main outcomes (depression: OR = 0.26, 95% CI: 0.19–0.37; anxiety: OR = 1.22, 95% CI: 0.14–0.33 and insomnia: OR = 0.18, 95% CI: 0.11–0.28). Furthermore, regular physical activity mitigated the risk for depression (OR = 0.79, 95% CI: 0.79–0.99).
Conclusions
The COVID-19 pandemic exerted a highly significant and negative impact on symptoms of depression, anxiety and insomnia. Mental health outcomes fluctuated as a function of the duration of the pandemic and were alleviated to some extent with the observed decline in community-based transmission. Augmenting resiliency and regular exercise provide an opportunity to mitigate the risk for mental health symptoms during this severe public health crisis.
To investigate the influences of dietary riboflavin (RF) addition on nutrient digestion and rumen fermentation, eight rumen cannulated Holstein bulls were randomly allocated into four treatments in a repeated 4 × 4 Latin square design. Daily addition level of RF for each bull in control, low RF, medium RF and high RF was 0, 300, 600 and 900 mg, respectively. Increasing the addition level of RF, DM intake was not affected, average daily gain tended to be increased linearly and feed conversion ratio decreased linearly. Total tract digestibilities of DM, organic matter, crude protein (CP) and neutral-detergent fibre (NDF) increased linearly. Rumen pH decreased quadratically, and total volatile fatty acids (VFA) increased quadratically. Acetate molar percentage and acetate:propionate ratio increased linearly, but propionate molar percentage and ammonia-N content decreased linearly. Rumen effective degradability of DM increased linearly, NDF increased quadratically but CP was unaltered. Activity of cellulase and populations of total bacteria, protozoa, fungi, dominant cellulolytic bacteria, Prevotella ruminicola and Ruminobacter amylophilus increased linearly. Linear increase was observed for urinary total purine derivatives excretion. The data suggested that dietary RF addition was essential for rumen microbial growth, and no further increase in performance and rumen total VFA concentration was observed when increasing RF level from 600 to 900 mg/d in dairy bulls.
The aim of this study was to explore the frequency and distribution of gene mutations that are related to isoniazid (INH) and rifampin (RIF)-resistance in the strains of the multidrug-resistant tuberculosis (MDR-TB) Mycobacterium tuberculosis (M.tb) in Beijing, China. In this retrospective study, the genotypes of 173 MDR-TB strains were analysed by spoligotyping. The katG, inhA genes and the promoter region of inhA, in which genetic mutations confer INH resistance; and the rpoB gene, in which genetic mutations confer RIF resistance, were sequenced. The percentage of resistance-associated nucleotide alterations among the strains of different genotypes was also analysed. In total, 90.8% (157/173) of the MDR strains belonged to the Beijing genotype. Population characteristics were not significantly different among the strains of different genotypes. In total, 50.3% (87/173) strains had mutations at codon S315T of katG; 16.8% (29/173) of strains had mutations in the inhA promoter region; of them, 5.5% (15/173) had point mutations at −15 base (C→T) of the inhA promoter region. In total, 86.7% (150/173) strains had mutations at rpoB gene; of them, 40% (69/173) strains had mutations at codon S531L of rpoB. The frequency of mutations was not significantly higher in Beijing genotypic MDR strains than in non-Beijing genotypes. Beijing genotypic MDR-TB strains were spreading in Beijing and present a major challenge to TB control in this region. A high prevalence of katG Ser315Thr, inhA promoter region (−15C→T) and rpoB (S531L) mutations was observed. Molecular diagnostics based on gene mutations was a useful method for rapid detection of MDR-TB in Beijing, China.
We have extended our previous work to use the Murchison widefield array (MWA) as a non-coherent passive radar system in the FM frequency band, using terrestrial FM transmitters to illuminate objects in low Earth orbit (LEO) and the MWA as the sensitive receiving element for the radar return. We have implemented a blind detection algorithm that searches for these reflected signals in difference images constructed using standard interferometric imaging techniques. From a large-scale survey using 20 h of archived MWA observations, we detect 74 unique objects over multiple passes, demonstrating the MWA to be a valuable addition to the global Space Domain Awareness network. We detected objects with ranges up to 977 km and as small as $0.03$${\rm m}^2$ radar cross section. We found that 30 objects were either non-operational satellites or upper-stage rocket body debris. Additionally, we also detected FM reflections from Geminid meteors and aircraft flying over the MWA. Most of the detections of objects in LEO were found to lie within the parameter space predicted by previous feasibility studies, verifying the performance of the MWA for this application. We have also used our survey to characterise these reflected signals from LEO objects as a source of radio frequency interference (RFI) that corrupts astronomical observations. This has allowed us to undertake an initial analysis of the impact of this RFI on the MWA and the future square kilometer array (SKA). As part of this analysis, we show that the standard MWA RFI flagging strategy misses most of this RFI and that this should be a careful consideration for the SKA.