116 research outputs found

    Kinetics of Strong Acid Hydrolysis of a Bleached Kraft Pulp for Producing Cellulose Nanocrystals (CNCs)

    No full text
    Cellulose nanocrytals (CNCs) are predominantly produced using the traditional strong acid hydrolysis process. In most reported studies, the typical CNC yield is low (approximately 30%) despite process optimization. This study investigated the hydrolysis of a bleached kraft eucalyptus pulp using sulfuric acid between 50 and 64 wt % at temperatures of 35–80 °C over time periods of up to 240 min for the production of CNCs. The experimental design captured the feature of the coexistence of a variety of reaction products, such as CNC, cellulosic solid residue (CSR), glucose, and xylose, in the product stream for accurate kinetic modeling to improve the CNC production yield. The kinetic model describing the solubilization of cellulose fibers used three phenomenological reactions, namely, hydrolysis of xylan to form xylose, depolymerization of cellulose to CNCs, and hydrolysis of cellulose to form glucose, each of which can be described by pseudohomogenous first-order kinetics. The concept of “degrees of hydrolyzable xylan or cellulose” to reflect the inhomogeneity of xylan or cellulose in hydrolysis was incorporated into the kinetic modeling to improve model accuracy. The developed model showed excellent predictability for CNC production. Both the experimental data and the model clearly indicate that CNC production was limited by cellulose depolymerization at low acid concentrations of below 58 wt %, but controlled by CNC degradation when the acid concentration was higher than 58 wt %. This work for the first time provides the most plausible description of CNC production kinetics, which is significant for the commercial production of CNCs

    Table_1_Association between statin use and acute pulmonary embolism in intensive care unit patients with sepsis: a retrospective cohort study.docx

    No full text
    IntroductionAcute pulmonary embolism (APE) is a life-threatening medical condition that is frequently encountered and associated with significant incidence and mortality rates, posing a substantial threat to patients’ well-being and quality of life. Sepsis is prominent independent risk factor for the development of APE. Despite recent investigations indicating a reduced APE risk through statin therapy, its impact on patients with sepsis and APE remains unresolved.MethodsThe Medical Information Mart for Intensive Care (MIMIC)-IV database was utilized to identify patients diagnosed with sepsis and APE, irrespective of statin treatment status, as part of this study. The primary study aim was to assess the risk of APE, which was analyzed using multivariate logistic regression models.ResultsThe study encompassed a total of 16,633 participants, with an average age of 64.8 ± 16.2 years. Multivariate logistic regression revealed that septic patients receiving statin therapy in the intensive care unit (ICU) exhibited a 33% reduction in the risk of developing APE (OR = 0.67, 95% CI: 0.52–0.86, p DiscussionThe results of the study provide compelling evidence in favor of administering statins to septic patients as a prophylactic measure against APE, given that statins may reduce the risk of developing APE, and their anti-APE effect appears to be dose-dependent. Nonetheless, future randomized controlled trials are needed to validate these results.</p

    Table_2_Association between statin use and acute pulmonary embolism in intensive care unit patients with sepsis: a retrospective cohort study.docx

    No full text
    IntroductionAcute pulmonary embolism (APE) is a life-threatening medical condition that is frequently encountered and associated with significant incidence and mortality rates, posing a substantial threat to patients’ well-being and quality of life. Sepsis is prominent independent risk factor for the development of APE. Despite recent investigations indicating a reduced APE risk through statin therapy, its impact on patients with sepsis and APE remains unresolved.MethodsThe Medical Information Mart for Intensive Care (MIMIC)-IV database was utilized to identify patients diagnosed with sepsis and APE, irrespective of statin treatment status, as part of this study. The primary study aim was to assess the risk of APE, which was analyzed using multivariate logistic regression models.ResultsThe study encompassed a total of 16,633 participants, with an average age of 64.8 ± 16.2 years. Multivariate logistic regression revealed that septic patients receiving statin therapy in the intensive care unit (ICU) exhibited a 33% reduction in the risk of developing APE (OR = 0.67, 95% CI: 0.52–0.86, p DiscussionThe results of the study provide compelling evidence in favor of administering statins to septic patients as a prophylactic measure against APE, given that statins may reduce the risk of developing APE, and their anti-APE effect appears to be dose-dependent. Nonetheless, future randomized controlled trials are needed to validate these results.</p

    DataSheet2_Fine mapping and characterization of RLL6 locus required for anti-silencing of a transgene and DNA demethylation in Arabidopsisthaliana.PDF

    No full text
    DNA methylation patterns in plants are dynamically shaped by the antagonistic actions of DNA methylation and demethylation pathways. Although the DNA methylation pathway has been well studied, the DNA demethylation pathway, however, are not fully understood so far. To gain deeper insights into the mechanisms of DNA demethylation pathway, we conducted a genetic screening for proteins that were involved in preventing epigenetic gene silencing, and then the ones, which were also implicated in DNA demethylation pathway, were used for further studies. Eventually, a mutant with low luciferase luminescence (low LUC luminescence) was recovered, and named reduced LUC luminescence 6–1 (rll6-1). Map-based cloning revealed that rll6-1 mutation was located on chromosome 4, and there were a total of 10 candidate genes residing within such a region. Analyses of genome-wide methylation patterns of rll6-1 mutant showed that mutation of RLL6 locus led to 3,863 hyper-DMRs (DMRs for differentially methylated regions) throughout five Arabidopsis chromosomes, and elevated DNA methylation level of 2 × 35S promoter, which was similar to that found in the ros1 (repressor of silencing 1) mutant. Further analysis demonstrated that there were 1,456 common hyper-DMRs shared by rll6-1 and ros1-7 mutants, suggesting that both proteins acted together in a synergistic manner to remove DNA methylation. Further investigations demonstrated that mutation of RLL6 locus did not affect the expression of the four genes of the DNA glycosylase/lyase family. Thus, our results demonstrate that RLL6 locus-encoded protein not only participates in transcriptional anti-silencing of a transgene, but is also involved in DNA demethylation pathway.</p

    Extremely Efficient and Recyclable Absorbents for Oily Pollutants Enabled by Ultrathin-Layered Functionalization

    No full text
    Oils and organic solvents that leak into water bodies must be promptly removed to avoid ecological disasters, for example, by selective absorption using oleophilic absorbents. However, it remains a challenge for the low-cost synthesis of efficient and recyclable absorbents for oily pollutants. By surface functionalization to inexpensive polyurethane (PU) foams, we synthesize oil absorbents exhibiting the highest absorption capacity and the best recyclability among all polymeric absorbents. The synthesis is enabled by atomic layer deposition of ∼5 nm-thick Al<sub>2</sub>O<sub>3</sub> transition layer onto the skeleton surface of PU foams, followed by coupling a single-molecule layer of silanes to the Al<sub>2</sub>O<sub>3</sub> layer. The sub-10 nm functionalization layer provides the PU foam an outstanding water-repelling and oil-absorbing functionality without compromising its high porosity and elasticity. The functionalized foam is able to quickly absorb oily pollutants spread on water surfaces or precipitated in water with a capacity more than 100 times its own weight. This ultrathin-layer-functionalization method is also applicable to renewable porous biomaterials, providing a sustainable solution for oil spills. Moreover, we propose devices than can continuously operate to efficiently collect oil spills from water surfaces based on the functionalized PU foam developed in this work

    MOESM1 of Characterizing dynamic behaviors of three-particle paramagnetic microswimmer near a solid surface

    No full text
    Additional file 1. This video demonstrates the microswimmer actuated under a rotating magnetic field at a frequency of 7 Hz and 9 Hz, and magnetic steering of the microswimmer

    Chemical constituents of the mangrove-associated fungus <i>Capnodium</i> sp. SZ-F22. A new eremophilane sesquiterpene

    No full text
    <p>A new eremophilane sesquiterpene, capnodiumone (<b>1</b>), along with five known eremophilane sesquiterpenes (<b>2–6</b>) and eight other compounds (<b>7–14</b>), have been isolated from a mangrove-associated fungus <i>Capnodium</i> sp. SZ-F22. The chemical structures were elucidated on the basis of extensive spectroscopic analysis. The broth extract of the fungus exhibited a good inhibitory effect on the mycelium growth against <i>Fusarium graminearum</i> at 100 μg/mL, however, all the 14 compounds showed no expected antifungal activity. The probable reasons were discussed.</p

    Time evolutions of interaction energy of EGCG with hIAPP<sub>1–37</sub> 5-mer on three sites based on the last 100 ns trajectory.

    No full text
    <p>Time evolutions of interaction energy of EGCG with hIAPP<sub>1–37</sub> 5-mer on three sites based on the last 100 ns trajectory.</p

    The averaged Cα RMSFs for each chain of hIAPP<sub>1–37</sub> oligomer as a function of residues.

    No full text
    <p>The averaged Cα RMSFs for each chain of hIAPP<sub>1–37</sub> oligomer as a function of residues.</p
    corecore