Recovery and Utilization of Lignin Monomers as Part of the Biorefinery Approach

Lignin is a substantial component of lignocellulosic biomass but is under-utilized relative to the cellulose and hemicellulose components. Historically, lignin has been burned as a source of process heat, but this heat is usually in excess of the process energy demands. Current models indicate that development of an economically competitive biorefinery system requires adding value to lignin beyond process heat. This addition of value, also known as lignin valorization, requires economically viable processes for separating the lignin from the other biomass components, depolymerizing the lignin into monomeric subunits, and then upgrading these monomers to a value-added product. The fact that lignin’s biological role is to provide biomass with structural integrity means that this heteropolymer can be difficult to depolymerize. However, there are chemical and biological routes to upgrade lignin from its native form to compounds of industrial value. Here we review the historical background and current technology of (thermo) chemical depolymerization of lignin; the natural ability of microbial enzymes and pathways to utilize lignin, the current prospecting work to find novel microbial routes to lignin degradation, and some applications of these microbial enzymes and pathways; and the current chemical and biological technologies to upgrade lignin-derived monomers

Combined Impact of Lifestyle-Related Factors on Total and Cause-Specific Mortality among Chinese Women: Prospective Cohort Study

Findings from the Shanghai Women's Health Study confirm those derived from other, principally Western, cohorts regarding the combined impact of lifestyle-related factors on mortality

Risk factors and prognosis for coronavirus disease 2019 among 131 hemodialysis patients during the Omicron variant epidemic

AbstractThe present study evaluated the presentations and outcomes of coronavirus disease 2019 (COVID-19) among patients undergoing maintenance hemodialysis (MHD) and the impact of the Omicron BF.7 variant. Adult patients (age ≥ 18 years), who underwent MHD (dialysis vintage ≥ 3 months) at the Hemodialysis Center at Beijing Tsinghua Changgung Hospital between December 2022 and January 2023, were included based on predefined eligibility criteria. Clinical and laboratory characteristics were retrospectively collected. Among 131 patients who underwent MHD (10.7% vaccination rate), 106 (80.9%) tested positive for COVID-19. The prevalence of asymptomatic, mild, moderate, and severe COVID-19 was 8.5%, 58.5%, 17%, and 16%, respectively. Among the 97 patients with symptoms, 23 (23.7%) were hospitalized and six (5.7%) died. Fever was experienced by 74.2% of patients and respiratory symptoms were the most common (81.4%). Residual symptoms persisted in 20.9% of patients one month after the onset of COVID-19. COVID-19-positive hemodialysis patients were more likely to experience weight loss and exhibit reduced albumin levels compared to those without COVID-19 (p < .05). Compared with the asymptomatic group, patients with symptoms were younger, and exhibited higher interleukin-6 levels and lower post-infection phosphate levels (p < .05). Age, dialysis vintage, comorbidities, and inflammatory factors were positively associated with disease severity, while baseline albumin and hemoglobulin levels were associated with death (p < .05). In conclusion, COVID-19 was prevalent among patients undergoing MHD, even during the Omicron variant epidemic. Age, nutritional status, comorbidities, and inflammatory factors were associated with disease severity and prognosis

On tensor decomposition, sparse interpolation and Padé approximation

What is the connection of tensor decomposition in multilinear algebra with exponential analysis from signal processing, sparse interpolation from computer algebra, Gaussian quadrature from numerical analysis, and Padé approximation theory? These seemingly unrelated and diverse topics are nevertheless deeply intertwined, as we explain here. However, several of these connections have remained unexplored. The various reformulations bring forth new ways to approach the problem of tensor decomposition (see Section 7) and suggestions for generalizations of existing methods (see Section 6). This may lead to important results since tensor decomposition has a number of grand applications [24], among others in chemometrics, neuroscience, computer vision, social network analysis, big data and the like. In Section 1 we introduce the problem statement. Subsequently the connections are first established for two-dimensional tensors in the sections 2 and 3. Higher dimensional tensors are dealt with in the sections 4 and 5, with a discussion of the connections to the mentioned topics in the sections 6 and 7. We conclude in Section 8 with an illustration of the interrelationships and of our novel approach. Both the existing method presented in Section 5 and the new technique presented in Section 7 are shown

Recovery and Utilization of Lignin Monomers as Part of the Biorefinery Approach

Lignin is a substantial component of lignocellulosic biomass but is under-utilized relative to the cellulose and hemicellulose components. Historically, lignin has been burned as a source of process heat, but this heat is usually in excess of the process energy demands. Current models indicate that development of an economically competitive biorefinery system requires adding value to lignin beyond process heat. This addition of value, also known as lignin valorization, requires economically viable processes for separating the lignin from the other biomass components, depolymerizing the lignin into monomeric subunits, and then upgrading these monomers to a value-added product. The fact that lignin’s biological role is to provide biomass with structural integrity means that this heteropolymer can be difficult to depolymerize. However, there are chemical and biological routes to upgrade lignin from its native form to compounds of industrial value. Here we review the historical background and current technology of (thermo) chemical depolymerization of lignin; the natural ability of microbial enzymes and pathways to utilize lignin, the current prospecting work to find novel microbial routes to lignin degradation, and some applications of these microbial enzymes and pathways; and the current chemical and biological technologies to upgrade lignin-derived monomers.This article is published as Davis, Kirsten M., Marjorie Rover, Robert C. Brown, Xianglan Bai, Zhiyou Wen, and Laura R. Jarboe. "Recovery and utilization of lignin monomers as part of the biorefinery approach." Energies 9, no. 10 (2016): 808. 10.3390/en9100808. Posted with permission.</p

Sex and cell-specific gene expression in corticolimbic brain regions associated with psychiatric disorders revealed by bulk and single-nuclei RNA sequencingResearch in context

Summary: Background: There are sex-specific differences in the prevalence, symptomology and course of psychiatric disorders. However, preclinical models have primarily used males, such that the molecular mechanisms underlying sex-specific differences in psychiatric disorders are not well established. Methods: In this study, we compared transcriptome-wide gene expression profiles in male and female rats within the corticolimbic system, including the cingulate cortex, nucleus accumbens medial shell (NAcS), ventral dentate gyrus and the basolateral amygdala (n = 22–24 per group/region). Findings: We found over 3000 differentially expressed genes (DEGs) in the NAcS between males and females. Of these DEGs in the NAcS, 303 showed sex-dependent conservation DEGs in humans and were significantly enriched for gene ontology terms related to blood vessel morphogenesis and regulation of cell migration. Single nuclei RNA sequencing in the NAcS of male and female rats identified widespread sex-dependent expression, with genes upregulated in females showing a notable enrichment for synaptic function. Female upregulated genes in astrocytes, Drd3+MSNs and oligodendrocyte were also enriched in several psychiatric genome-wide association studies (GWAS). Interpretation: Our data provide comprehensive evidence of sex- and cell-specific molecular profiles in the NAcS. Importantly these differences associate with anxiety, bipolar disorder, schizophrenia, and cross-disorder, suggesting an intrinsic molecular basis for sex-based differences in psychiatric disorders that strongly implicates the NAcS. Funding: This work was supported by funding from the Hope for Depression Research Foundation (MJM)

Environmental enrichment increases transcriptional and epigenetic differentiation between mouse dorsal and ventral dentate gyrus

Environmental enrichment has functional and molecular effects on mammalian hippocampus. Here, Zhang and colleagues show that environmental enrichment of mice is correlated with dorsal-ventral asymmetry in transcription and DNA methylation of the dentate gyrus