Improving microalgal growth by strengthening the flashing light effect simulated with computational fluid dynamics in a panel bioreactor with horizontal baffles

Biological CO₂ elimination by photosynthetic microalgae is a sustainable way to mitigate CO₂ from flue gas and other sources. Computational fluid dynamics was used to simulate algal cell movement with an enhanced flashing light effect in a novel panel bioreactor with horizontal baffles. Calculation results showed that the light/dark (L/D) cycle period decreased by 17.5% from 17.1 s to 14.1 s and that the horizontal fluid velocity increased by 95% while horizontal baffles were used under a 0.02 vvm air aeration rate and a microalgal concentration of 0.85 g L⁻¹. The probability of the L/D cycle period within 5–10 s increased from 27.9% to 43.6%, indicating a 56% increase when horizontal baffles existed. It was proved by experiments that the mass-transfer coefficient increased by 31% and the mixing time decreased by 13% under a 0.06 vvm air aeration rate when horizontal baffles were used, and the algal biomass yield increased by ∼51% along with the decrease in the L/D cycle period when horizontal baffles were used.

Biological CO₂ elimination by photosynthetic microalgae is a sustainable way to mitigate CO₂ from flue gas and other sources.     

Characteristics of negative DC discharge in a wire–cylinder configuration under coal pyrolysis gas components at high temperatures

This work aims to provide a comprehensive understanding of negative DC discharge under coal pyrolysis gas components (CO₂, H₂, N₂, CH₄, CO) and air. The characteristics of negative DC discharge were studied in a wire–cylinder configuration at an ambient temperature range of 20–600 °C by analyzing V–I characteristics, discharge photographs, and gas composition. With increasing temperature, corona onset voltage, spark breakdown voltage and operational voltage range for corona discharge decrease, but discharge current and electron current ratio increase. Discharge current of CO₂ is higher than that of air due to the difference of electronegativity. During CO₂ discharge, with the increase of output voltage, three types of discharge are successively observed, namely corona, glow and arc. However, during H₂ discharge, only glow discharge is observed. Temperatures significantly affect the capability of CO to attach electrons. The discharge characteristic of CO is similar to the electronegative gas media at 20 °C and the non-electronegative gas media when the temperature exceeds 350 °C. Chemical reactions and carbon generation are observed during the CH₄ and CO discharge process. The product of carbon filaments under the CH₄ gas medium leads to discharge current volatility and short circuit. These results assist in understanding the property of ESP at high temperatures.

This work aims to provide a comprehensive understanding of negative DC discharge under coal pyrolysis gas components (CO₂, H₂, N₂, CH₄, CO) and air.     

愈肝胶囊抗鸭乙型肝炎病毒作用实验研究

观察愈肝胶囊抗鸭乙型肝炎病毒作用。方法选1日龄广州麻鸭50只接种病毒,分ACV200μg/kg,愈肝胶囊6.5g/kg,3.25g/kg及病毒对照组,1/d,口服。分别观察其抗DHBV的作用。试验结束时,取肝组织作病理切片光镜观察。结果 6.5g/kg愈肝胶囊组在给药后第5天,第10天和停药后第3天,鸭血清DHBV DNA水平均明显下降,与给药前自身比及病毒对照组比较,差异均有显著性(P相似文献   

Systemic Inflammatory Response Syndrome is Associated with Hematoma Expansion in Intracerebral Hemorrhage

ObjectivesSystemic inflammatory response syndrome (SIRS) and hematoma expansion are independently associated with worse outcomes after intracerebral hemorrhage (ICH), but the relationship between SIRS and hematoma expansion remains unclear.Materials and methodsWe performed a retrospective review of patients admitted to our hospital from 2013 to 2020 with primary spontaneous ICH with at least two head CTs within the first 24 hours. The relationship between SIRS and hematoma expansion, defined as ≥6 mL or ≥33% growth between the first and second scan, was assessed using univariable and multivariable regression analysis. We assessed the relationship of hematoma expansion and SIRS on discharge mRS using mediation analysis.ResultsOf 149 patients with ICH, 83 (56%; mean age 67±16; 41% female) met inclusion criteria. Of those, 44 (53%) had SIRS. Admission systolic blood pressure (SBP), temperature, antiplatelet use, platelet count, initial hematoma volume and rates of infection did not differ between groups (all p>0.05). Hematoma expansion occurred in 15/83 (18%) patients, 12 (80%) of whom also had SIRS. SIRS was significantly associated with hematoma expansion (OR 4.5, 95% CI 1.16 - 17.39, p= 0.02) on univariable analysis. The association remained statistically significant after adjusting for admission SBP and initial hematoma volume (OR 5.72, 95% CI 1.40 – 23.41, p= 0.02). There was a significant indirect effect of SIRS on discharge mRS through hematoma expansion. A significantly greater percentage of patients with SIRS had mRS 4-6 at discharge (59 vs 33%, p=0.02).ConclusionSIRS is associated with hematoma expansion of ICH within the first 24 hours, and hematoma expansion mediates the effect of SIRS on poor outcome.     

Benchmarking Various Radiomic Toolkit Features While Applying the Image Biomarker Standardization Initiative toward Clinical Translation of Radiomic Analysis

Journal of Digital Imaging - The image biomarkers standardization initiative (IBSI) was formed to address the standardization of extraction of quantifiable imaging metrics. Despite its effort,...     

Amoxicillin for acute lower respiratory tract infection in primary care: subgroup analysis of potential high-risk groups

Background

Antibiotics are of limited overall clinical benefit for uncomplicated lower respiratory tract infection (LRTI) but there is uncertainty about their effectiveness for patients with features associated with higher levels of antibiotic prescribing.

Aim

To estimate the benefits and harms of antibiotics for acute LRTI among those producing coloured sputum, smokers, those with fever or prior comorbidities, and longer duration of prior illness.

Design and setting

Secondary analysis of a randomised controlled trial of antibiotic placebo for acute LRTI in primary care.

Method

Two thousand and sixty-one adults with acute LRTI, where pneumonia was not suspected clinically, were given amoxicillin or matching placebo. The duration of symptoms, rated moderately bad or worse (primary outcome), symptom severity on days 2–4 (0–6 scale), and the development of new or worsening symptoms were analysed in pre-specified subgroups of interest. Evidence of differential treatment effectiveness was assessed in prespecified subgroups by interaction terms.

Results

No subgroups were identified that were significantly more likely to benefit from antibiotics in terms of symptom duration or the development of new or worsening symptoms. Those with a history of significant comorbidities experienced a significantly greater reduction in symptom severity between days 2 and 4 (interaction term −0.28, P = 0.003; estimated effect of antibiotics among those with a past history −0.28 [95% confidence interval = −0.44 to −0.11], P = 0.001), equivalent to three people in 10 rating symptoms as a slight rather than a moderately bad problem. For subgroups not specified in advance antibiotics provided a modest reduction in symptom severity for non-smokers and for those with short prior illness duration (<7 days), and a modest reduction in symptom duration for those with short prior illness duration.

Conclusion

There is no clear evidence of clinically meaningful benefit from antibiotics in the studied high-risk groups of patients presenting in general practice with uncomplicated LRTIs where prescribing is highest. Any possible benefit must be balanced against the side-effects and longer-term effects on antibiotic resistance.