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According to a WHO report, the number of patients with coronavirus disease 2019 (COVID-19) has reached 456,797,217 worldwide as of 15 March, 2022. In Wuhan, China, large teams of healthcare personnel were dispatched to respond to the COVID-19 emergency. This study aimed to determine the sociodemographic and psychological predictors of resilience among frontline nurses fighting the current pandemic.
A total of 143 nurses were recruited from February 15 to February 20, 2020 to participate in this study. The 10-item Connor–Davidson Resilience Scale and the 21-item Depression Anxiety Stress Scale were used to estimate the participants’ resilience and mental wellbeing.
Results showed that the nurses displayed a moderate resilience level. Their median depression, anxiety, and stress scores were 1, 2, and 3, respectively, which were negatively correlated with resilience. Female gender, being dispatched to Wuhan, and depression levels were the significant predictors of resilience.
The results suggest that particular attention should be given to female nurses who were dispatched to Wuhan and who exhibited depression symptoms, and appropriate measures should be taken to boost their resilience.
Echinococcus granulosus sensu lato has complex defence mechanisms that protect it from the anti-parasitic immune response for long periods. Echinococcus granulosus cyst fluid (EgCF) is involved in the immune escape. Nevertheless, whether and how EgCF modulates the inflammatory response in macrophages remains poorly understood. Here, real-time polymerase chain reaction and enzyme-linked immunosorbent assay revealed that EgCF could markedly attenuate the lipopolysaccharide (LPS)-induced production of pro-inflammatory factors including tumour necrosis factor-α, interleukin (IL)-12 and IL-6 but increase the expression of IL-10 at mRNA and protein levels in mouse peritoneal macrophages and RAW 264.7 cells. Mechanically, western blotting and immunofluorescence assay showed that EgCF abolished the activation of nuclear factor (NF)-κB p65, p38 mitogen-activated protein kinase (MAPK) and ERK1/2 signalling pathways by LPS stimulation in mouse macrophages. EgCF's anti-inflammatory role was at least partly contributed by promoting proteasomal degradation of the critical adaptor TRAF6. Moreover, the EgCF-promoted anti-inflammatory response and TRAF6 proteasomal degradation were conserved in human THP-1 macrophages. These findings collectively reveal a novel mechanism by which EgCF suppresses inflammatory responses by inhibiting TRAF6 and the downstream activation of NF-κB and MAPK signalling in both human and mouse macrophages, providing new insights into the molecular mechanisms underlying the E. granulosus-induced immune evasion.
A 1178 J near diffraction limited 527 nm laser is realized in a complete closed-loop adaptive optics (AO) controlled off-axis multi-pass amplification laser system. Generated from a fiber laser and amplified by the pre-amplifier and the main amplifier, a 1053 nm laser beam with the energy of 1900 J is obtained and converted into a 527 nm laser beam by a KDP crystal with 62% conversion efficiency, 1178 J and beam quality of 7.93 times the diffraction limit (DL). By using a complete closed-loop AO configuration, the static and dynamic wavefront distortions of the laser system are measured and compensated. After correction, the diameter of the circle enclosing 80% energy is improved remarkably from 7.93DL to 1.29DL. The focal spot is highly concentrated and the 1178 J, 527 nm near diffraction limited laser is achieved.
The mortality of coronavirus disease 2019 (COVID-19) differs between countries and regions. This study aimed to clarify the clinical characteristics of imported and second-generation cases in Shaanxi. This study included 134 COVID-19 cases in Shaanxi outside Wuhan. Clinical data were compared between severe and non-severe cases. We further profiled the dynamic laboratory findings of some patients. In total, 34.3% of the 134 patients were severe cases, 11.2% had complications. As of 7 March 2020, 91.8% patients were discharged and one patient (0.7%) died. Age, lymphocyte count, C-reactive protein, erythrocyte sedimentation rate, direct bilirubin, lactate dehydrogenase and hydroxybutyrate dehydrogenase showed difference between severe and no-severe cases (all P < 0.05). Baseline lymphocyte count was higher in survived patients than in non-survivor case, and it increased as the condition improved, but declined sharply when death occurred. The interleukin-6 (IL-6) level displayed a downtrend in survivors, but rose very high in the death case. Pulmonary fibrosis was found on later chest computed tomography images in 51.5% of the pneumonia cases. Imported and second-generation cases outside Wuhan had a better prognosis than initial cases in Wuhan. Lymphocyte count and IL-6 level could be used for evaluating prognosis. Pulmonary fibrosis as the sequelae of COVID-19 should be taken into account.
CHD is closely related to respiratory system diseases (Mok Q, Front Pediatr 2017; 5: 2296–2360). Flexible fibreoptic bronchoscopy will diagnose anatomical lesions of the trachea and perform interventions at the same time for children with indications. We report a case of pulmonary artery sling with severe tracheostenosis in a 11-month-old boy. Tracheal stents were placed with good prognosis.
OBJECTIVES/GOALS: The desmoplastic reaction in PDAC involves a significant accumulation of immune cells and fibroblasts.The functional diversity of carcinoma associated fibroblasts (CAFs) remains largely unknown, and identification of immune regulating subsets would have a substantial impact in augmentation of immunotherapy efficacy. METHODS/STUDY POPULATION: Employing histology, FACs, multiplex immunohistochemistry, single cell RNA sequencing (sc-RNA-seq) and genetically engineered mouse models, we demonstrate that aSMA+ cells are a dominant CAF population in PDAC with tumor restraining properties (TS-CAFs), as opposed those of the FAP+ CAFs, which demonstrate tumor promoting activity (TP-CAFs). RESULTS/ANTICIPATED RESULTS: Analysis of bulk tumor depleted of either TS-CAFs or TP-CAFs showed that TS-CAFs predominantly modulate extracellular matrix (ECM) production, facilitate cell-ECM adhesion and regulate adaptive immunity, while TP-CAFs exhibit a lineage that is skewed towards a pro-inflammatory, chemokine secreting phenotype. Further, scRNA-Seq analyses demonstrate that CAFs share distinct gene expression profiles characteristic of lymphocytic and myeloid lineages. Together our data distinguish two populations of CAFs, one which is tumor suppressing with roles in ECM remodeling and another which is tumor promoting with roles in cytokine production, both with immune modulating capabilities. DISCUSSION/SIGNIFICANCE OF IMPACT: Our study identifies a complex network of functionally heterogeneous fibroblasts during PDAC progression with significant immunotherapeutic implication. The identification of distinct fibroblast subsets will allow us to discriminately target fibroblast populations to augment immunotherapy efficacy in pancreatic cancer.
Using ethanol adsorption calorimetry, the surface energetics of two carbon substrates and two products in microwave-assisted carbon nanotube (CNT) growth was studied. In this study, the ethanol adsorption enthalpies of the two graphene-based samples at 25 °C were measured successfully. Specifically, the near-zero differential enthalpies of ethanol adsorption are −75.7 kJ/mol for graphene and −63.4 kJ/mol for CNT-grafted graphene. Subsequently, the differential enthalpy curve of each sample becomes less exothermic until reaching a plateau, −55.8 kJ/mol for graphene and −49.7 kJ/mol for CNT-grafted graphene, suggesting favorable adsorbate–adsorbent binding. Moreover, the authors interpreted and discussed the partial molar entropy and chemical potential of adsorption as the ethanol surface coverage (loading) increases. Due to the low surface areas of carbon black–based samples, adsorption calorimetry could not be performed. This model study demonstrates that using adsorption calorimetry as a fundamental tool and ethanol as the molecular probe, the overall surface energetics of high–surface area carbon materials can be estimated.
The deformation of the Mach stem in pseudo-steady shock wave reflections is investigated numerically and theoretically. The numerical simulation provides the typical flow patterns of Mach stem deformation and reveals the differences caused by high-temperature gas effects. The results also show that the wall jet, which causes Mach stem deformation, can be regarded as a branch of the mainstream from the first reflected shock. A new theoretical model for predicting the Mach stem deformation is developed by considering volume conservation. The theoretical predictions agree well with the numerical results in a wide range of test conditions. With this model, the wall-jet velocity and the inflow velocity from the Mach stem are identified as the two dominating factors that convey the influence of high-temperature thermodynamics. The mechanism of high-temperature gas effects on the Mach stem deformation phenomenon are then discussed.
Rotation vector-based attitude updating algorithms have been used as the mainstream attitude computation algorithms for many years. The most popular methodology for designing the rotation vector algorithm is by leveraging multiple samples of gyro integrated angular rate measurements. However, it has been pointed out by many researchers that the attitude updating accuracy is limited when using the multiple samples rotation vector algorithms, especially when the platforms work under high rate manoeuvres. The third-, fourth-, fifth- and sixth-order Picard component solutions of the rotation vector differential equation are given in this paper. A new design methodology for rotation vector-based attitude updating algorithms is proposed. Different vibratory dynamics and high rate manoeuvre roller coaster experiments were conducted to validate the effectiveness of the new algorithm. The results demonstrate the high accuracy of the new algorithm compared with conventional coning correction methods. The proposed algorithm can also be used in high accuracy attitude computation of a post-processing system, especially when the output frequency of the gyro is limited.
In this paper, we present some efficient numerical schemes to solve a two-phase hydrodynamics coupled phase field model with moving contact line boundary conditions. The model is a nonlinear coupling system, which consists the Navier-Stokes equations with the general Navier Boundary conditions or degenerated Navier Boundary conditions, and the Allen-Cahn type phase field equations with dynamical contact line boundary condition or static contact line boundary condition. The proposed schemes are linear and unconditionally energy stable, where the energy stabilities are proved rigorously. Various numerical tests are performed to show the accuracy and efficiency thereafter.
The commonly used incompressible phase field models for non-reactive, binary fluids, in which the Cahn-Hilliard equation is used for the transport of phase variables (volume fractions), conserve the total volume of each phase as well as the material volume, but do not conserve the mass of the fluid mixture when densities of two components are different. In this paper, we formulate the phase field theory for mixtures of two incompressible fluids, consistent with the quasi-compressible theory , to ensure conservation of mass and momentum for the fluid mixture in addition to conservation of volume for each fluid phase. In this formulation, the mass-average velocity is no longer divergence-free (solenoidal) when densities of two components in the mixture are not equal, making it a compressible model subject to an internal con-straint. In one formulation of the compressible models with internal constraints (model 2), energy dissipation can be clearly established. An efficient numerical method is then devised to enforce this compressible internal constraint. Numerical simulations in confined geometries for both compressible and the incompressible models are carried out using spatially high order spectral methods to contrast the model predictions. Numerical comparisons show that (a) predictions by the two models agree qualitatively in the situation where the interfacial mixing layer is thin; and (b) predictions differ significantly in binary fluid mixtures undergoing mixing with a large mixing zone. The numerical study delineates the limitation of the commonly used incompressible phase field model using volume fractions and thereby cautions its predictive value in simulating well-mixed binary fluids.
Fast linear transformer driver (FLTD) has some advantages in repetitive operation compared with traditional pulsed power generators. However, different types of gas switches applied in the field of pulsed power technology in recent years cannot reach the requirements of repetitive operation of FLTD. Therefore, the capability of repetitive operation of a multigap gas switch has been investigated in a circuit similar to the basic discharge loop named as brick in this paper. The switch has been triggered more than 2000 times and the distribution of delay time and switch jitter are analyzed and reported. Also, the self-breakdown voltages of the switch during different segments of the triggered breakdown experiment have been tested. The experimental results indicate that the delay time obeys the Gauss distribution and the jitter of 2000 times of discharge is about 2.3 ns.
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