Activity

Lignin is a potential biomass feedstock from plant material, but it is particularly difficult to economically process. Inspired by recent ball-milling results, state-of-the-art quantum mechanochemistry calculations have been performed to isolate and probe the purely mechanochemical stretching effect alone upon acid-catalyzed deconstruction of lignin. Effects upon cleavage of several exemplary simple ethers are examined first, and with low stretching force they all are predicted to cleave substantially faster, allowing for use of milder acids and lower temperatures. Effects upon an experimentally known lignin fragment model (containing the ubiquitous β-O-4 linkage) are next examined; this first required a mechanism refinement (3-step indirect cleavage, 1-step side reaction) and identification of the rate-limiting step under zero-force (thermal) conditions. Mechanochemical activation using very low stretching forces improves at first only yield, by fully shutting off the ring-closure side reaction. At only somewhat larger forces, in stark contrast, a switch in mechanism is found to occur, from 3-step indirect cleavage to the direct cleavage mechanism of simple ethers, finally strongly enhancing the cleavage rate of lignin. It is concluded that mechanochemical activation of the common β-O-4 link in lignin would improve the rate of its acidolysis via a mechanism switch past a low force threshold. Relevance to ball-milling experiments is discussed.

This study factor analyzes six scales relating to acculturation and related experiences among a nationally representative sample of United States-residing Latina/os (n = 2,541) from the National Latino and Asian American Study (NLAAS), using measurement invariance (MI) testing to explore differences in latent constructs by Latina/o subgroup.

Factor Analysis (FA) within an Exploratory Structural Equation Modeling framework was used to analyze the factor structure of six scales measuring acculturation and related experiences (i.e., acculturation [language use and preference], enculturation [ethnic identity], discrimination, neighborhood context, and family environment). We tested for MI by two important Latina/o subgroups ethnic heritage and generational status.

The underlying latent factors resulting from FA strongly aligned with the NLAAS subscales. No scale achieved full MI, yet the degree to which MI held varied greatly by scale and by subgroup.

Findings show that Latina/os are heterogeneous, but that this often depends on the construct and subgrouping of interest. Future research should use these scales in a latent framework, accounting for the lack of MI, to ensure that the underlying acculturative constructs of interest are validly measured when investigating their association with mental health outcomes in this population.

Findings show that Latina/os are heterogeneous, but that this often depends on the construct and subgrouping of interest. Future research should use these scales in a latent framework, accounting for the lack of MI, to ensure that the underlying acculturative constructs of interest are validly measured when investigating their association with mental health outcomes in this population.

To investigate global patterns of cardiovascular risk factor control in patients with type 2 diabetes mellitus (T2D).

DISCOVER is an international, observational cohort study of patients with T2D beginning second-line glucose-lowering therapy. Risk factor management was examined among eligible patients (ie, those with the risk factor) at study baseline. Inter-country variability was estimated using median odds ratios (MORs).

Among 14 343 patients with T2D from 34 countries, the mean age was 57.4 ± 12.0 years and the median (interquartile range) duration of T2D was 4.2 (2.0-8.0) years; 11.8% had documented atherosclerotic cardiovascular disease (ASCVD). Among eligible patients, blood pressure was controlled in 67.5% (9284/13756), statins were prescribed in 43.7% (5775/13208), angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers were prescribed in 55.6% (5292/9512), aspirin was prescribed in 53.3% of those with established ASCVD (876/1645), and 84.4% (12 102/14343) were non-smoking. Only 21.5% of patients (3088/14343) had optimal risk factor management (defined as control of all eligible measures), with wide inter-country variability (10%-44%), even after adjusting for patient and site differences (MOR 1.47, 95% confidence interval 1.24-1.66).

Globally, comprehensive control of ASCVD risk factors is not being achieved in most patients, with wide variability among countries unaccounted for by patient and site differences. Better country-specific strategies are needed to implement comprehensive cardiovascular risk factor control consistently in patients with T2D to improve long-term outcomes.

Globally, comprehensive control of ASCVD risk factors is not being achieved in most patients, with wide variability among countries unaccounted for by patient and site differences. Better country-specific strategies are needed to implement comprehensive cardiovascular risk factor control consistently in patients with T2D to improve long-term outcomes.

In children, vitamin D deficiency is common after renal transplantation. Besides promoting bone and muscle development, vitamin D has immunomodulatory effects, which could protect kidney allografts. The purpose of this study was to assess the association between vitamin D status and the occurrence of renal rejection.

We studied a retrospective cohort of 123 children, who were transplanted at a single institution between September 2008 and April 2019. Patients did not receive vitamin D supplementation systematically. In addition, factors influencing vitamin D status were analyzed using univariate and multivariate analyses.

Median 25-hydroxy-vitamin D (25-OH-D) concentration was close to reference values at the time of transplantation (30ng/mL (min-max 5-100)), but rapidly decreased within the first 3months to 19ng/mL (min-max 3-91) (P<.001). The overall acute rejection rate was 7%. Antineoplastic and I inhibitor The clinical rejection rate (5% vs 9%), subclinical rejection (12% vs 36%), and borderline changes (21% vs 28%) were not statistically different during the follow-up between the 3-month 25-OH-D<20ng/mL and 3-month 25-OH-D>20ng/mL groups.