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1.
Adv Mater ; : e2402170, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587064

RESUMO

The rapid advancement of prevailing communication/sensing technologies necessitates cost-effective millimeter-wave arrays equipped with a massive number of phase-shifting cells to perform complicated beamforming tasks. Conventional approaches employing semiconductor switch/varactor components or tunable materials encounter obstacles such as quantization loss, high cost, high complexity, and limited adaptability for realizing large-scale arrays. Here, a low-cost, ultrathin, fast-response, and large-scale solution relying on metasurface concepts combined together with liquid crystal (LC) materials requiring a layer thickness of only 5 µm is reported. Rather than immersing resonant structures in LCs, a joint material-circuit-based strategy is devised, via integrating deep-subwavelength-thick LCs into slow-wave structures, to achieve constitutive metacells with continuous phase shifting and stable reflectivity. An LC-facilitated reconfigurable metasurface sub-system containing more than 2300 metacells is realized with its unprecedented comprehensive wavefront manipulation capacity validated through various beamforming functions, including beam focusing/steering, reconfigurable vortex beams, and tunable holograms, demonstrating a milli-second-level function-switching speed. The proposed methodology offers a paradigm shift for modulating electromagnetic waves in a non-resonating broadband fashion with fast-response and low-cost properties by exploiting functionalized LC-enabled metasurfaces. Moreover, this extremely agile metasurface-enabled antenna technology will facilitate a transformative impact on communication/sensing systems and empower new possibilities for wavefront engineering and diffractive wave calculation/inference.

2.
Front Pharmacol ; 14: 1292745, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38034989

RESUMO

Background: Aspirin, with its pleiotropic effects such as anti-inflammatory and anti-platelet aggregation, has been widely used for anti-inflammatory, analgesic, and cardiovascular diseases. However, the association between the use of aspirin before the intensive care unit (ICU) and clinical outcomes in critically ill patients with acute kidney injury (AKI) is unknown. Methods: Patients with AKI in this retrospective observational study were selected from the Marketplace for Medical Information in Intensive Care IV (MIMIC-IV). The association between aspirin intervention and 30-day mortality was assessed using Cox proportional hazards model. Logistic regression models were used to assess the association of aspirin intervention with the risks of intracranial hemorrhage, gastrointestinal bleeding and blood transfusion. The propensity score matching (PSM) method was adopted to balance the baseline variables. Sensitivity analysis was performed to validate the results by multiple interpolations for the missing data. Results: The study included 4237 pre-ICU aspirin users and 9745 non-users. In multivariate models, we found a decreased risk of mortality in those who received aspirin before ICU compared to those who did not (30-day:hazard ratio [HR], 0.70; 95% CI, 0.62-0.79; p < 0.001; 90-day:HR, 0.70; 95% CI, 0.63-0.77, p < 0.001; 180-day:HR, 0.72; 95%CI,0.65-0.79, p < 0.001). This benefit was consistent in the post-PSM analyses, sensitivity analyses, and subgroup analyses. Moreover, aspirin intervention was associated with a reduced risk of intracranial hemorrhage and gastrointestinal bleeding (HR, 0.16; 95% CI, 0.10-0.25; p < 0.001; HR, 0.59; 95% CI, 0.38-0.88, p = 0.012) after being adjusted by relating covariates, whereas with a increased risk of blood transfusion (HR, 1.28; 95% CI, 1.16-1.46; p < 0.001). Conclusion: Patients with AKI treated with aspirin before ICU admission might have reduced 30-day, 90-day and 180-day mortality without increasing the risk of intracranial hemorrhage (ICH) or gastrointestinal bleeding, but may increase the risk of transfusion.

3.
Chinese Journal of Rheumatology ; (12): 666-670, 2011.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-671635

RESUMO

ObjectiveTo investigate the clinical features of systemic lupus erythematosus (SLE) patients with fever and find out the related factors.MethodsData was collected by the same methods in the past ten years in fifteen hospitals in Jiangsu province and then the data wereretrospectively analyzed.The potentially possible risk factors of fever in SLE were selected and then analyzed by chi-square test,Wilcoxon rank sum test and Logistic regression analysis.ResultsAll 1762 patients were investigated.Seven hundred and twenty-nine had active fever.Age at hospitalization,initially treated patients,photosensitivity,serositis,nervous system involvement,generalized lymphadenopathy/hepatosplenomegaly,white blood cell count (WBC),haemoglobin (HB),erythrocyte sedimentation rate (ESR),C-reaction protein (CRP),alanine aminotransferase(ALT),albumin(ALB),serum creatinine (Scr),complement C3,anti-dsDNA antibodies positive rate,anti-Sm antibodies positive rate,SLEDAI score and past therapies were factors associatedwith SLE fever.Logistic regression analysis showed that abnormal WBC count (OR=1.396,95%CI 1.114-1.711,P=0.004),CRP(OR=1.005,95%CI 1.002-1.009,P=0.002),ALT(OR=1.003,95%CI 1.001-1.005,P=0.005),Scr (OR=0.997,95%CI0.995-0.999,P=0.007),HB (OR=0.986,95%CI 0.981-0.992,P=0.000),age (OR =0.984,95% CI 0.974-0.993,P=0.001 ) and past usage of cyclophosphamide (CTX) (OR =0.557,95%CI 0.382-0.813,P=0.002) were correlated with SLE fever.ConclusionFever is one of the most common clinical manifestations of SLE patients.Leucopenia,elevated CRP levels,liver function abnormalities,anemia,younger age are risk factors for SLE fever,while renal impairment and past usage of CTX are protective factors.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-682742

RESUMO

Objective To observe the effect of dexamethasone(Dex)on the proliferation and os- teogenic differentiation of human marrow stromal cells(MSCs)in vitro.Methods The primary human MSCs were isolated and cultured by Ficoll seperation culture in vitro.In subcultures,human MSCs were respectively treated with dexamethasone 10~(-9),10~(-8) and 10~(-7) mol/L.The proliferation of human MSCs was measured using MTF method;cytoplasmic alkaline phosphatase(ALP)activity was measured;the osteogenic marker osteopontin (OPN)mRNA were examined by reverse transcriptase polymerase chain reaction(RT-PCR).Results The op- tical density values in cultures treated with dexamethasone 10~(-8) and 10~(-7) mol/L for 8 days were significantly lower than those in the controls(P<0.05).Treatment of cells with Dex for 12 days led to a significant increase in cytoplasmic ALP activity(P<0.05)in a dose-dependent manner.Dex induced OPN mRNA.Conclusion Dex inhibits the proliferation of human MSCs and dexamethasone 10~(-7) mol/L leads to a strong decrease in cell number.Dex induces human MSCs differentiate to osteoblastic cells.

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