Online monitoring lignocellulosic particles by focus beam reflectance measurement for efficient bioprocessing.

Lignocellulose presents a promising alternative to fossil fuels. Monitoring the mass and size changes of lignocellulosic particles without disrupting the process can assist in adjusting pretreatment and enzymatic hydrolysis, where conventional sieving methods fall short. A method utilizing focused beam reflectance measurement (FBRM) was developed to establish mathematical correlations between FBRM chord information (chord length and count) and particle characteristics (weight and size) quantified through sieving. Results indicate particle size exhibits a linear correlation with the square weighted median chord length (Lsqr) with R2 at 0.93. Further, real-time bulk particle mass can be predicted using Lsqr and chord count (R2 0.98). These correlations are applicable in range 53 µm to 358.5 µm. Real-time monitoring of enzymatic hydrolysis of corn stalks has demonstrated the practical applicability of FBRM. This study introduces a novel approach for online characterization of lignocellulosic particles, thereby enhancing lignocellulosic biorefineries.

Prognosis of Older Adult Patients Suffering from Atrial Fibrillation and Hypokalemia.

Objective: To examine the effects of hypokalemia on the prognosis of older adult patients with atrial fibrillation (AF). Methods: We enrolled 794 older adult patients ≥ 75 years suffering from AF, and divided them into two groups according to the inclusion and exclusion criteria: Group 1, (hypokalemia group), 246 cases, serum K+<3.5 mmol/L; Group 2, (normal blood potassium group), 548 cases, 3.5mmol/L≤serum K+<5.5 mmol/L. The two groups of patients were followed for 70 months to observe the occurrence of clinical events. The primary endpoint was cardiovascular death and the secondary endpoint was all-cause death. Results: The median follow-up time was 15.00 months. In terms of baseline profile characteristics, serum creatinine levels were significantly lower in Group 1 than in Group 2 patients (P=0.002). In terms of the relationship between hypokalemia and clinical outcomes, Kaplan-Meier survival analysis revealed that the incidence of clinical primary endpoint in Group 1 was significantly higher than that in Group 2 (P < 0.001), and the incidence of the secondary endpoint did not differ significantly between the two groups (P> 005). Based on multivariate Cox regression risk model analysis, coronary heart disease, hemoglobin content, serum uric acid and usage of anticoagulant drugs were the independent variables related to the primary endpoint of cardiovascular death (all P< 0.01). Conclusion: The incidence of hypokalemia in older adult patients with AF was 30.98%. Hypokalemia was closely related to the cardiovascular death, and coronary heart disease, hemoglobin content, serum uric acid level, and usage of anticoagulant drugs were the independent risk factors for the primary endpoint event.

Deciphering Molecular Mechanism Underlying Self-Flocculation of Zymomonas mobilis for Robust Production.

Zymomonas mobilis metabolizes sugar anaerobically through the Entner-Doudoroff pathway with less ATP generated for lower biomass accumulation to direct more sugar for product formation with improved yield, making it a suitable host to be engineered as microbial cell factories for producing bulk commodities with major costs from feedstock consumption. Self-flocculation of the bacterial cells presents many advantages, such as enhanced tolerance to environmental stresses, a prerequisite for achieving high product titers by using concentrated substrates. ZM401, a self-flocculating mutant developed from ZM4, the unicellular model strain of Z. mobilis, was employed in this work to explore the molecular mechanism underlying this self-flocculating phenotype. Comparative studies between ZM401 and ZM4 indicate that a frameshift caused by a single nucleotide deletion in the poly-T tract of ZMO1082 fused the putative gene with the open reading frame of ZMO1083, encoding the catalytic subunit BcsA of the bacterial cellulose synthase to catalyze cellulose biosynthesis. Furthermore, the single nucleotide polymorphism mutation in the open reading frame of ZMO1055, encoding a bifunctional GGDEF-EAL protein with apparent diguanylate cyclase/phosphodiesterase activities, resulted in the Ala526Val substitution, which consequently compromised in vivo specific phosphodiesterase activity for the degradation of cyclic diguanylic acid, leading to intracellular accumulation of the signaling molecule to activate cellulose biosynthesis. These discoveries are significant for engineering other unicellular strains from Z. mobilis with the self-flocculating phenotype for robust production. IMPORTANCE Stress tolerance is a prerequisite for microbial cell factories to be robust in production, particularly for biorefinery of lignocellulosic biomass to produce biofuels, bioenergy, and bio-based chemicals for sustainable socioeconomic development, since various inhibitors are released during the pretreatment to destroy the recalcitrant lignin-carbohydrate complex for sugar production through enzymatic hydrolysis of the cellulose component, and their detoxification is too costly for producing bulk commodities. Although tolerance to individual stress has been intensively studied, the progress seems less significant since microbial cells are inevitably suffering from multiple stresses simultaneously under production conditions. When self-flocculating, microbial cells are more tolerant to multiple stresses through the general stress response due to enhanced quorum sensing associated with the morphological change for physiological and metabolic advantages. Therefore, elucidation of the molecular mechanism underlying such a self-flocculating phenotype is significant for engineering microbial cells with the unique multicellular morphology through rational design to boost their production performance.

The Impact of the Duration of Cardiac Troponin I Elevation on the Clinical Prognosis as Well as Incidence of New-Onset Atrial Fibrillation Respectively in Elderly Non-ST-Elevation Acute Myocardial Infarction Patients without PCI.

OBJECTIVE: This study aimed to investigate the impact of the duration of cardiac troponin I (TnI) elevation on the prognosis and incidence of new-onset atrial fibrillation (NOAF) in elderly patients with non-ST-elevation acute myocardial infarction (NSTE-AMI). METHODS: A total of 383 NSTE-AMI patients ≥75 years old were enrolled in this study and divided into two groups: in 194 cases, the duration of TnI elevation was ≥14 days (group 1), and in 189 cases, the duration of TnI elevation was <14 days (group 2). The patients were followed up for 60 months. The effect of TnI on prognosis was studied by cohort. The primary endpoint was a composite endpoint of cardiovascular death, reinfarction, ischemic stroke, and hospitalization for heart failure, and the secondary endpoint was all-cause death. A case-control study design was adopted to analyze the influencing factors of NOAF occurrence in Group 1 and Group 2. RESULTS: The median duration of follow-up was 26 months. Multivariate Cox's regression analysis revealed that the duration of TnI elevation ≥14 days and diuretic use were independent variables of the major composite endpoint (p < 0.01 for both), and the left ventricular ejection fraction and the duration of TnI elevation ≥14 days were independent related variables of all-cause death (p < 0.05). The duration of TnI elevation ≥14 days was correlated with the occurrence of NOAF, but, in the multivariate logistic regression model, only uric acid and high-sensitivity C-reactive protein were independently associated with NOAF (p < 0.05). CONCLUSION: The duration of TnI elevation ≥14 days was the independent correlation factor of the major composite endpoint and all-cause death; high sensitivity C-reactive protein and uric acid are independent risk factors for NOAF.