Abstract
The plasma-beta effect on the
n
= 1 resonant magnetic perturbation (RMP) field penetration in purely radio-frequency (RF) wave heated discharges has been investigated in EAST. The ...experimental results show that the dependence of the threshold RMP coil current for field penetration,
I
RMP,th
, on the total absorbed power
P
tot
scales as approximately
I
RMP,th
∝
P
tot
0.30
, indicating that the error-field tolerance is improved with increasing RF power. This is benefited by the increased electron perpendicular flow dominated by a counter-current electron diamagnetic flow with increasing RF power. However, theoretical scaling in cylindrical geometry overestimates the power index. Assuming an additional term
β
N
α
β
N
for the normalized beta in the scaling, it is shown that the fitted
α
β
N
from the experimental observation is around −1, indicating a degradation effect of plasma beta. To clarify the underlying physics of the plasma-beta effect that was not included in the theoretical scaling in cylindrical geometry, the MARS-Q code with full toroidal geometry is employed for simulation of nonlinear field penetration (Liu
et al
2013
Phys. Plasmas
20
042503). The MARS-Q simulation results reproduce the
β
N
dependence well, and hence the
P
tot
scaling of the threshold current in experimental observations. The main reason for this is that the net total torque, which is mainly contributed by the neoclassical toroidal viscosity (NTV), increases with increasing plasma
β
N
. The results demonstrate that the nonlinear toroidal coupling effect via NTV torque plays an important role in determining field penetration, even in cases with relatively low
β
N
∈
0.3
,
0.6
, which is far less than the no-wall beta limit.
B cells play vital roles in host defense against
Pneumocystis
infection. However, the features of the B cell receptor (BCR) repertoire in disease progression remain unclear. Here, we integrated ...single-cell RNA sequencing and single-cell BCR sequencing of immune cells from mouse lungs in an uninfected state and 1–4 weeks post-infection in order to illustrate the dynamic nature of B cell responses during
Pneumocystis
infection. We identified continuously increased plasma cells and an elevated ratio of (IgA + IgG) to (IgD + IgM) after infection. Moreover,
Pneumocystis
infection was associated with an increasing naïve B subset characterized by elevated expression of the transcription factor
ATF3
. The proportion of clonal expanded cells progressively increased, while BCR diversity decreased. Plasma cells exhibited higher levels of somatic hypermutation than naïve B cells. Biased usage of V(D)J genes was observed, and the usage frequency of
IGHV9-3
rose. Overall, these results present a detailed atlas of B cell transcriptional changes and BCR repertoire features in the context of
Pneumocystis
infection, which provides valuable information for finding diagnostic biomarkers and developing potential immunotherapeutic targets.
Abstract Constructing well‐defined active multisites is an effective strategy to break linear scaling relationships to develop high‐efficiency catalysts toward multiple‐intermediate reactions. Here, ...dual‐intermetallic heterostructure composed of tungsten‐bridged Co 3 W and WNi 4 intermetallic compounds seamlessly integrated on hierarchical nanoporous nickel skeleton is reported as a high‐performance nonprecious electrocatalyst for alkaline hydrogen evolution and oxidation reactions. By virtue of interfacial tungsten atoms configuring contiguous multisites with proper adsorptions of hydrogen and hydroxyl intermediates to accelerate water dissociation/combination and column‐nanostructured nickel skeleton facilitating electron and ion/molecule transportations, nanoporous nickel‐supported Co 3 W–WNi 4 heterostructure exhibits exceptional hydrogen electrocatalysis in alkaline media, with outstanding durability and impressive catalytic activities for hydrogen oxidation reaction (geometric exchange current density of ≈6.62 mA cm −2 ) and hydrogen evolution reaction (current density of ≈1.45 A cm −2 at overpotential of 200 mV). Such atom‐ordered intermetallic heterostructure alternative to platinum group metals shows genuine potential for hydrogen production and utilization in hydroxide‐exchange‐membrane water electrolyzers and fuel cells.
Psittacosis can cause severe community-acquired pneumonia (CAP). The clinical manifestations of psittacosis range from subclinical to fulminant psittacosis with multi-organ failure. It is essential ...to summarize the clinical characteristic of patients with severe psittacosis accompanied by acute hypoxic respiratory failure (AHRF).
This retrospective study included patients with severe psittacosis caused CAP accompanied by AHRF from 19 tertiary hospitals of China. We recorded the clinical data, antimicrobial therapy, respiratory support, complications, and outcomes. Chlamydia psittaci was detected on the basis of metagenomic next-generation sequencing performed on bronchoalveolar lavage fluid samples. Patient outcomes were compared between the treatment methods.
This study included 45 patients with severe CAP and AHRF caused by psittacosis from April 2018 to May 2021. The highest incidence of these infections was between September and April. There was a history of poultry contact in 64.4% of the patients. The median PaO
/FiO
of the patients was 119.8 (interquartile range, 73.2 to 183.6) mmHg. Four of 45 patients (8.9%) died in the ICU, and the median ICU duration was 12 days (interquartile range, 8 to 21) days. There were no significant differences between patients treated with fluoroquinolone initially and continued after the diagnosis, fluoroquinolone initially followed by tetracycline, and fluoroquinolone combined with tetracycline.
Psittacosis caused severe CAP seems not rare, especially in the patients with the history of exposure to poultry or birds. Empirical treatment that covers atypical pathogens may benefit such patients, which fluoroquinolones might be considered as an alternative.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract An experiment was conducted to study the mode penetration of n = 1 resonant magnetic perturbation (RMP) in EAST under low neutral beam injection torque in the co-current direction (Co-NBI). ...The experimental results indicate that the threshold current I RMP,th for field penetration decreases with higher input torque T NBI . Furthermore, it is observed that the plasma mode frequency | f MHD | at counter-current direction is greatly reduced when the plasma toroidal rotation frequency f ϕ increases. The theoretical scaling of mode frequency ( I RMP,th ∝ | f MHD | 0.70 ) predicted by the field penetration theory is in good agreement with the experimental observation ( I RMP,th ∝ | f MHD | 0.53 ). The role of | f MHD | and f ϕ on the mode onset threshold was separately investigated using the full toroidal geometry initial value code MARS-Q (Liu et al 2013 Phys. Plasmas 20 042503). The numerical scaling based on the experimental mode frequency is consistent with the experimental and theoretical ones. Numerical results suggest that evaluating the total mode frequency | f MHD | is crucial in field penetration analysis, in contrast to toroidal rotation frequency f ϕ . With the increase of T NBI , the decreasing | f MHD | leads to a reduction in the field penetration threshold. This suggests that more attention should be paid to error field tolerance in low Co-NBI torque scenarios, where the electron diamagnetic frequency may be canceled out by NBI-driven toroidal plasma rotation.
CDGSH iron sulfur domain 2 can inhibit ferroptosis, which has been associated with cerebral ischemia/reperfusion, in individuals with head and neck cancer. Therefore, CDGSH iron sulfur domain 2 may ...be implicated in cerebral ischemia/reperfusion injury. To validate this hypothesis in the present study, we established mouse models of occlusion of the middle cerebral artery and HT22 cell models of oxygen-glucose deprivation and reoxygenation to mimic cerebral ischemia/reperfusion injury in vivo and in vitro, respectively. We found remarkably decreased CDGSH iron sulfur domain 2 expression in the mouse brain tissue and HT22 cells. When we used adeno-associated virus and plasmid to up-regulate CDGSH iron sulfur domain 2 expression in the brain tissue and HT22 cell models separately, mouse neurological dysfunction was greatly improved; the cerebral infarct volume was reduced; the survival rate of HT22 cells was increased; HT22 cell injury was alleviated; the expression of ferroptosis-related glutathione peroxidase 4, cystine-glutamate antiporter, and glutathione was increased; the levels of malondialdehyde, iron ions, and the expression of transferrin receptor 1 were decreased; and the expression of nuclear-factor E2-related factor 2/heme oxygenase 1 was increased. Inhibition of CDGSH iron sulfur domain 2 upregulation via the nuclear-factor E2-related factor 2 inhibitor ML385 in oxygen-glucose deprived and reoxygenated HT22 cells blocked the neuroprotective effects of CDGSH iron sulfur domain 2 up-regulation and the activation of the nuclear-factor E2-related factor 2/heme oxygenase 1 pathway. Our data indicate that the up-regulation of CDGSH iron sulfur domain 2 can attenuate cerebral ischemia/reperfusion injury, thus providing theoretical support from the perspectives of cytology and experimental zoology for the use of this protein as a therapeutic target in patients with cerebral ischemia/reperfusion injury.
Due to the extremely high bond energy of NN (∼941 kJ/mol), the traditional Haber–Bosch process of ammonia synthesis is known as an energy-intensive and high CO2-emission industry. In this paper, a ...cascade N2 reduction process with dielectric barrier discharge (DBD) plasma oxidation and electrocatalytic reduction as an alternative route is first proposed. N2 is oxidized to be reactive nitrogen species (RNS) by nonthermal plasma, which would then be absorbed by KOH solution and electroreduced to NH4 +. It is found that the production of NO x is a function of discharge length, discharge power, and gas flow rate. Afterward, the cobalt catalyst is used in the process of electrocatalytic reduction of ammonia, which shows high selectivity (Faradic efficiency (FE) above 90%) and high yield of ammonia (45.45 mg/h). Finally, the cascade plasma oxidation and electrocatalytic reduction for ammonia synthesis is performed. Also, the performance of the reaction system is evaluated. It is worth mentioning that a stable and sustainable ammonia production efficiency of 16.21 mg/h is achieved, and 22.16% of NO x obtained by air activation is converted into NH4 +. This work provides a demonstration for further industrial application of ammonia production with DBD plasma oxidation and electrocatalytic reduction techniques.
Background
Following endotracheal intubation, clearing secretions above the endotracheal tube cuff decreases the incidence of ventilator-associated pneumonia (VAP); therefore, subglottic secretion ...drainage (SSD) is widely advocated. Our group developed a novel technique to remove the subglottic secretions, the rapid-flow expulsion maneuver (RFEM). The objective of this study was to explore the effectiveness and safety of RFEM compared with SSD.
Methods
This study was a single-center, prospective, randomized and controlled trial, conducted at Respiratory Intensive Care Unit (ICU) of Beijing Chao-Yang Hospital, a university-affiliated tertiary hospital. The primary outcome was the incidence of VAP, assessed for non-inferiority.
Results
Patients with an endotracheal tube allowing drainage of subglottic secretions (
n
= 241) were randomly assigned to either the RFEM group (
n
= 120) or SSD group (
n
= 121). Eleven patients (9.17%) in the RFEM group and 13 (10.74%) in the SSD group developed VAP (difference, − 1.59; 95% confidence interval CI − 9.20 6.03), as the upper limit of 95% CI was not greater than the pre-defined non-inferiority limit (10%), RFEM was declared non-inferior to SSD. There were no statistically significant differences in the duration of mechanical ventilation, ICU mortality, or ICU length of stay and costs between groups. In terms of safety, no accidental extubation or maneuver-related barotrauma occurred in the RFEM group. The incidence of post-extubation laryngeal edema and reintubation was similar in both groups.
Conclusions
RFEM is effective and safe, with non-inferiority compared to SSD in terms of the incidence of VAP. RFEM could be an alternative method in first-line treatment of respiratory ICU patients.
Trial registration
This study has been registered on ClinicalTrials.gov (Registration Number: NCT02032849,
https://clinicaltrials.gov/ct2/show/NCT02032849
); registered on January 2014
Critically ill patients in intensive care units (ICUs) are at high risk of venous thromboembolism (VTE). This study aimed to explore the prophylaxis effect under a guideline-based thromboprophylaxis ...protocol among critically ill patients in a respiratory ICU.
For this single-center prospective cohort study, we followed the thromboprophylaxis protocol, which was drawn up based on relevant guidelines and Chinese experts' advice. Clinical data were entered into an electronic case report form and analyzed. Multivariate logistic regression was conducted to explore independent risk factors of VTE event under this protocol.
From August 1, 2014, to December 31, 2020, 884 patients underwent thromboprophylaxis according to this protocol; 10.5% of them received mechanical prophylaxis, 43.8% received pharmacological prophylaxis, and 45.7% received pharmacological combined with mechanical prophylaxis. The proportion of VTE events was 14.3% for patients who received the thromboprophylaxis protocol, of which 0.1% had pulmonary thromboembolism (PTE), 2.0% had proximal deep vein thrombosis (DVT), and 12.1% had isolated distal DVT. There was no significant difference between different thromboprophylaxis measures. Cirrhosis (OR 5.789, 95% CI 1.402, 23.894, P = 0.015), acute asthma exacerbation (OR 39.999, 95% CI 4.704, 340.083, P = 0.001), and extracorporeal membrane oxygenation treatment (OR 22.237, 95%CI 4.824, 102.502, P < 0.001) were independent risk factors for proximal DVT under thromboprophylaxis.
The thromboprophylaxis protocol based on guidelines applied in the ICU was practicable and could help decrease the proportion of PTE and proximal DVT events. The risk factors of VTE events happening under the thromboprophylaxis protocol require more attention.
ClinicalTrials.gov: NCT02213978.
The multi-messenger observation of coalescing compact binary systems promises great scientific treasure. However, synthesising observations from both gravitational wave and electromagnetic channels ...remains challenging. In the context of the day-to-week long emission from a macronova, the binary neutron star merger GW170817 remains the only event with successful electromagnetic followup. In this manuscript, we explore the possibility of using the early stage X-ray afterglow to search for the electromagnetic counterpart of a gravitational wave event. Two algorithms, the simple and straightforward sequential observation (SO) and the step-wise optimizing local optimization are considered and applied to some simulated events. We consider the WXT from the proposed Einstein Probe as a candidate X-ray telescope, which has a very wide field of view of 3600 deg2. Benefiting from the large field of view and high sensitivity, we find that the SO algorithm not only is easy to implement, but also promises a good chance of actual detection.
PDF
