COVID-19 is an acute, complex disorder that was caused by a new β-coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Based on current reports, it was surprising that the ...characteristics of many patients with COVID-19, who fulfil the Berlin criteria for acute respiratory distress syndrome (ARDS), are not always like those of patients with typical ARDS and can change over time. While the mechanisms of COVID-19–related respiratory dysfunction in COVID-19 have not yet been fully elucidated, pulmonary microvascular thrombosis is speculated to be involved. Considering that thrombosis is highly related to other inflammatory lung diseases, immunothrombosis, a two-way process that links coagulation and inflammation, seems to be involved in the pathophysiology of COVID-19, including respiratory dysfunction. Thus, the current manuscript will describe the proinflammatory milieu in COVID-19, summarize current evidence of thrombosis in COVID-19, and discuss possible interactions between these two.
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•A novel sensor was synthesized for simultaneous detection of AA and acac.•Both proposed sensing systems showed high KSV values and low LOD.•Probable sensing mechanism are discussed ...in more detail.
A novel Cu(II) coordination polymer Cu(HL)(4,4′-bpy)n (4,4′-bpy = 4,4′-bipyridine) 1 based on a semi-rigid tricarboxylate, 5-(3,4-dicarboxylphenoxy) nicotinic acid (H3L) has been hydrothermally synthesized. Single-crystal X-ray diffraction analysis indicates that, in compound 1, H3L ligands first extend the metal ions into a 2-D layer. Then the 4,4′-bpy molecules functioned as bidentate bridge, strutting the 2-D layers into a 3-D open network with a (63) (69·8) topology. Notably, 1-D channels of ca. 6.5 × 10.5 Å2 are observed in 1, but due to 2-fold interpenetration phenomenon, these channels become small or disappear. Fluorescent spectra indicate 1 can act as a muti-chemosensor for detection of acetylacetone (Hacac), Cr2O72− and CrO42− in aqueous solution with high selectivity and sensitivity. The mechanism of luminescent sensing Hacac and Cr(VI) were also investigated in detail.
A one-dimensional (1D) Ni(II) coordination polymer (CP), Ni(H2L)2(bpe)(H2O)2bpe·(H2O)4 (1) (H3L = 4-(2′,3′-dicarboxylphenoxy) benzoic acid; bpe = 1,2-bis(4-pyridyl) ethylene) was constructed from ...a semi-rigid tricarboxylate acid H3L. Owing to the extraordinary moisture susceptibility and fluorescence property, compound 1 displays high sensitive and selective detectivity as a dual-response fluorescence probe for ascorbic acid and acetylacetone in aqueous phase via fluorescence “turn on” and “turn off” mechanism, respectively. It's worth noting that 1 exhibits rare turn-on responsive effect to AA. Both proposed systems exhibit excellent performance with outstanding anti-interference ability as well as good reusability. Besides, the mechanisms of fluorescence sensing were also investigated in detail. This work expands the practical applications of stable CPs in the detection of biological molecules and organic pollutants in aqueous phase.
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•A new luminescent Ni(II)-CP was prepared for detecting Hacac and AA.•This compound exhibits rare turn-on responsive effect to AA.•The possible sensing mechanisms are also discussed in detail.
We report Q-switching and mode-locking operations in a Ho 3+ /Pr 3+ co-doped ZBLAN fiber laser at 3-μm mid-infrared waveband using a single-walled carbon nanotube saturable absorber (SWCNT-SA). The ...SWCNTs were produced by catalytic chemical vapor deposition method and then deposited on the surface of a flat gold-coated mirror to form the SWCNT-SA. The modulation depth and saturation intensity of the SWCNT-SA are 16.5% and 1.66 MW/cm 2 , respectively. Stable Q-switched laser pulses operating at 2865.6 nm were obtained at a launched pump power of 530.6 mW. The resulting pulses have a measured repetition rate and pulse width of 178.6 kHz and 1.21 μs, respectively. The maximum pulse energy is calculated to be 0.36 μJ. By slightly adjusting the position of the SWCNT-SA, stable continuous-wave mode-locked pulses at 2865.2 nm were also achieved. Our work demonstrates that SWCNTs are promising SAs for 3-μm midinfrared pulsed lasers.
Direct water injection (DWI) within internal combustion engine has become a promising technology due to its potential for suppressing knock, reducing emissions and lowering fuel consumption. The ...spray morphology shows a significant impact on the effectiveness of DWI, which makes it of great research significance. In this research, the spray characteristics of water jet under different conditions were investigated based on a constant volume vessel. The water injection temperature ranged from 30 °C to 240 °C, and the ambient pressure varied from 0.2 bar to 10 bar. The results showed that the spray width at near-field increases with water temperature. However, at ambient pressures of 0.8 bar–2.5 bar, higher superheat level resulted in severe spray collapse, manifested as significantly reduced spray width. It was identified that the collapse under flash boiling occurs as a result of the presence of the low-pressure zone at the center of the spray, and higher superheat level migrate the low-pressure zone closer to the nozzle exit, resulting in enhanced spray collapse. This could lead to excessive water mist concentration in partial region, negatively affecting combustion process and potentially causing oil emulsion in actual engine operation. This work also suggests a strong correlation between spray collapse and water injection pressure, in addition to superheat level and ambient pressure. The findings of this work have the potential to provide effective reference for high-temperature water injection strategies in internal combustion engines.
The compression ignition internal combustion Rankine cycle (CI-ICRC) is a novel combustion cycle that integrates oxy-fuel combustion, direct water injection (DWI), and waste heat recovery into diesel ...cycle to achieve ultra-high thermal efficiency and zero emissions. NOX formation is eliminated by utilizing oxygen instead of air, and water is injected into the cylinder to improve thermal efficiency. To achieve over 50% indicated thermal efficiency in the CI-ICRC engine, a thermodynamic model of the CI-ICRC engine is established in this paper to explore the potential thermal efficiency and boundary under different DWI strategies. Theoretical results demonstrate that the thermal efficiency of CI-ICRC engine is mostly affected by DWI mass and temperature, the thermal efficiency is dramatically enhanced as DWI mass and temperature increase. Under a water-to-fuel ratio of 20 and DWI temperature of 423K, the calculated thermal efficiency reaches 76.8%. Moreover, exhaust waste heat is mainly recovered through DWI, which increases the working fluid within the combustion chamber, thereby increasing the expansion work and improving cyclic thermal efficiency. Additionally, specific heat ratio of the mixture within the cylinder can be enhanced by 0.04 through DWI, improving the thermal efficiency by 9% at an in-cylinder temperature of 800 K.
•A theoretical thermodynamics model of CI-ICRC engine is established.•Effects of DWI strategies on CI-ICRC thermal efficiency are calculated.•The mechanism of CI-ICRC thermal efficiency enhancement is proposed.•The differences between the theoretical and actual thermal efficiency of CI-ICRC are studied.
A single electro-optical (EO) sensor used in space debris observation provides angle-only information. However, space debris position can be derived using simultaneous optical measurements obtained ...from two EO sensors located at two separate observation sites, and this is commonly known as triangulation. In this paper, we propose a new triangulation algorithm to determine space debris position, and its analytical expression of Root-Mean-Square (RMS) position error is presented. The simulation of two-site observation is conducted to compare the RMS positioning error of the proposed triangulation algorithm with traditional triangulation algorithms. The results show that the maximum RMS position error of the proposed triangulation algorithm is not more than 200 m, the proposed triangulation algorithm has higher positioning accuracy than traditional triangulation algorithms, and the RMS position error obtained in the simulation is nearly consistent with the analytical expression of RMS position error. In addition, initial orbit determination (IOD) is carried out by using the triangulation positioning data, and the results show that the IOD accuracy of two-site observation is significantly higher than that of the single-site observation.
BackgroundThe pregnant women with intrahepatic cholestasis were at high risk of fetal distress, preterm birth and unexpected stillbirth. Intrahepatic cholestasis of pregnancy (ICP) was mainly caused ...by disorder of bile acid metabolism, whereas the specific mechanism was obscure.MethodsWe performed proteomics analysis of 10 ICP specimens and 10 placenta specimens from patients without ICP through data-independent acquisition (DIA) technique to disclose differentially expressed proteins. We executed metabolomic analysis of 30 ICP specimens and 30 placenta specimens from patients without ICP through UPLC-MS/MS to identify differentially expressed metabolites. Enrichment and correlation analysis was used to obtain the direct molecular insights of ICP development. The ICP rat models were constructed to validate pathological features.ResultsThe heatmap of proteomics analysis showed the top 30 up-regulated and 30 down-regulated proteins. The metabolomic analysis revealed 20 richer and 4 less abundant metabolites in ICP samples compared with placenta specimens from patients without ICP, and enrichment pathways by these metabolites included primary bile acid biosynthesis, cholesterol metabolism, bile secretion, nicotinate and nicotinamide metabolism, purine metabolism and metabolic pathways. Combined analysis of multiple omics results demonstrated that bile acids such as Glycohyocholic acid, Glycine deoxycholic acid, beta-Muricholic acid, Noncholic acid, cholic acid, Gamma-Mercholic Acid, alpha-Muricholic acid and Glycochenodeoxycholic Aicd were significantly associated with the expression of GLRX3, MYL1, MYH7, PGGT1B, ACTG1, SP3, LACTB2, C2CD5, APBB2, IPO9, MYH2, PPP3CC, PIN1, BLOC1S1, DNAJC7, RASAL2 and ATCN3 etc. The core protein ACAT2 was involved in lipid metabolic process and animal model showed that ACAT2 was up-regulated in placenta and liver of pregnant rats and fetal rats. The neonates had low birth weight and Safranin O-Fast green FCF staining of animal models showed that poor osteogenic and chondrogenic differentiation of fetal rats.ConclusionMultiple metabolites-alpha-Muricholic acid, beta-Muricholic acid, Glycine deoxycholic acid and Glycochenodeoxycholic Acid etc. were perfect biomarkers to predict occurrence of ICP. Bile acids were significantly associated with varieties of protein expression and these proteins were differentially expressed in ICP samples. Our study provided several biomarkers for ICP detection and potential therapeutic targets for ICP development.
To summarise evidence of the effects of blood pressure (BP)-lowering interventions after acute spontaneous intracerebral haemorrhage (ICH).
A prespecified systematic review of the Cochrane Central ...Register of Controlled Trials, EMBASE and MEDLINE databases from inception to 23 June 2020 to identify randomised controlled trials that compared active BP-lowering agents versus placebo or intensive versus guideline BP-lowering targets for adults <7 days after ICH onset. The primary outcome was function (distribution of scores on the modified Rankin scale) 90 days after randomisation. Radiological outcomes were absolute (>6 mL) and proportional (>33%) haematoma growth at 24 hours. Meta-analysis used a one-stage approach, adjusted using generalised linear mixed models with prespecified covariables and trial as a random effect.
Of 7094 studies identified, 50 trials involving 11 494 patients were eligible and 16 (32.0%) shared patient-level data from 6221 (54.1%) patients (mean age 64.2 SD 12.9, 2266 36.4% females) with a median time from symptom onset to randomisation of 3.8 hours (IQR 2.6-5.3). Active/intensive BP-lowering interventions had no effect on the primary outcome compared with placebo/guideline treatment (adjusted OR for unfavourable shift in modified Rankin scale scores: 0.97, 95% CI 0.88 to 1.06; p=0.50), but there was significant heterogeneity by strategy (p
=0.031) and agent (p
<0.0001). Active/intensive BP-lowering interventions clearly reduced absolute (>6 ml, adjusted OR 0.75, 95%CI 0.60 to 0.92; p=0.0077) and relative (≥33%, adjusted OR 0.82, 95%CI 0.68 to 0.99; p=0.034) haematoma growth.
Overall, a broad range of interventions to lower BP within 7 days of ICH onset had no overall benefit on functional recovery, despite reducing bleeding. The treatment effect appeared to vary according to strategy and agent.
CRD42019141136.
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