The Hydration, Microstructure, And Mechanical Properties Of Vaterite Calcined Clay Cement (VC³)

Limestone (calcite) calcined clay cement (LC3) is a promising low-CO2 binder, but the low activity of calcite cannot compensate the reduction in clinker factor, resulting in low one-day strength and limiting its broad applications. As recent carbon capture and utilization technologies allow scalable production of vaterite, a more reactive CaCO3 polymorph, we overcome the challenge by introducing vaterite calcined clay cement (VC3), inspired by the vaterite-calcite phase change. In the present study, VC3 exhibits higher compressive strengths and faster hydration than LC3. Compared to hydrated LC3, hydrated VC3 exhibits increased amount of hemi- and mono-carboaluminate formation and decreased amount of strätlingite formation. With gypsum adjustment, the 1-day strength of VC3 is higher than that of pure cement reference. VC3, a low-CO2 binder, presents great potential as a host of the metastable CaCO3 for carbon storage and utilization and as an enabler of carbon capture at gigaton scales

Some new results for B1 B_1 -matrices

The class of $B_1$-matrices is a subclass of $P$-matrices and introduced as a generalization of $B$-matrices. In this paper, we present several properties for $B_1$-matrices. Then, the infinity norm upper bound for the inverse of $B_1$-matrices is obtained. Furthermore, the error bound for the linear complementarity problem of $B_1$-matrices is presented. Finally, some numerical examples are given to illustrate our results

Elevated monocyte-to-HDL cholesterol ratio predicts post-stroke depression

ObjectivesInflammation plays an important role in the development of depression after stroke. Monocyte-to-HDL Cholesterol Ratio (MHR) recently emerged as a novel comprehensive inflammatory indicator in recent years. This study aimed to investigate whether there is a relationship between MHR levels and post-stroke depression (PSD).MethodsFrom February 2019 to September 2021, patients with acute ischemic stroke (AIS) were recruited within 7 days post-stroke from the two centers and blood samples were collected after admission. The 17-item Hamilton Depression Scale (HAMD-17) was used to measure depressive symptoms at 3 months after stroke. Patients were given the DSM-V criteria for diagnosis of PSD.ResultsOf the 411 enrolled patients, 92 (22.38%) patients were diagnosed with PSD at 3-months follow-up. The results also showed significantly higher level of MHR in patients with depression [0.81 (IQR 0.67–0.87) vs. 0.61 (IQR 0.44–0.82), P < 0.001] at admission than patients without depression. Multivariate logistic regression revealed that MHR (OR 6.568, 95% CI: 2.123–14.565, P = 0.015) was an independent risk factor for the depression at 3 months after stroke. After adjustment for potential confounding factors, the odds ratio of PSD was 5.018 (95% CI: 1.694–14.867, P = 0.004) for the highest tertile of MHR compared with the lowest tertile. Based on the ROC curve, the optimal cut-off value of MHR as an indicator for prediction of PSD was projected to be 0.55, which yielded a sensitivity of 87% and a specificity of 68.3%, with the area under the curve at 0.660 (95% CI: 0.683–0.781; P = 0.003).ConclusionElevated level of MHR was associated with PSD at 3 months, suggesting that MHR might be a useful Inflammatory markers to predict depression after stroke

Effects of Proteins on Protein Diffusion

Despite increased attention, little is known about how the crowded intracellular environment affects basic phenomena like protein diffusion. Here, we use NMR to quantify the rotational and translational diffusion of a 7.4-kDa test protein, chymotrypsin inhibitor 2 (CI2), in solutions of glycerol, synthetic polymers, proteins, and cell lysates. As expected, translational diffusion and rotational diffusion decrease with increasing viscosity. In glycerol, for example, the decrease follows the Stokes-Einstein and Stokes-Einstein-Debye laws. Synthetic polymers cause negative deviation from the Stokes Laws and affect translation more than rotation. Surprisingly, however, protein crowders have the opposite effect, causing positive deviation and reducing rotational diffusion more than translational diffusion. Indeed, bulk proteins severely attenuate the rotational diffusion of CI2 in crowded protein solutions. Similarly, CI2 diffusion in cell lysates is comparable to its diffusion in crowded protein solutions, supporting the biological relevance of the results. The rotational attenuation is independent of the size and total charge of the crowding protein, suggesting that the effect is general. The difference between the behavior of synthetic polymers and protein crowders suggests that synthetic polymers may not be suitable mimics of the intracellular environment. NMR relaxation data reveal that the source of the difference between synthetic polymers and proteins is the presence of weak interactions between the proteins and CI2. In summary, weak but non-specific, non-covalent chemical interactions between proteins appear to fundamentally impact protein diffusion in cells

Translational and Rotational Diffusion of a Small Globular Protein under Crowded Conditions

Protein protein interaction is the fundamental step of biological signal transduction. Interacting proteins find each other by diffusion. To gain insight into diffusion under the crowded conditions found in cells, we used nuclear magnetic resonance spectroscopy (NMR) to measure the effects of solvent additives on the translational and rotational diffusion of the 7.4 kDa globular protein, chymotrypsin inhibitor 2. The additives were glycerol and the macromolecular crowding agent, polyvinylpyrrolidone (PVP). Both translational diffusion and rotational diffusion decrease with increasing solution viscosity. For glycerol, the decrease obeys the Stokes Einstein and Stokes Einstein Debye laws. Three types of deviation are observed for PVP: the decrease in diffusion with increased viscosity is less than predicted, this negative deviation is greater for rotational diffusion, and the negative deviation increases with increasing PVP molecular weight. We discuss our results in terms of other studies on the effects of macromolecules on globular protein diffusion