Difference in oral microbial composition between chronic periodontitis patients with and without diabetic nephropathy

Background To investigate the difference in the structural composition of salivary flora between chronic periodontitis patients with and without diabetic nephropathy (DN). Methods Thirty salivary samples of 15 chronic periodontitis patients with DN (DN group) and 15 chronic periodontitis patients with diabetes but without DN (DM group) were subjected to pyrosequencing of polymerase chain reaction-amplified 16 s ribosomal RNA genes. After diversity testing, the differential flora were analyzed. The sequencing results were compared with GenBank database to determine the type of differential flora using species composition analysis, hierarchical cluster analysis, principal co-ordinate analysis, and species difference analysis. Results There were significant between-group differences with respect to Gemella, Selenomonas spp, Lactobacillales_unclassified, Bacteria-unclassified and Abiotrophia (p < 0.05). Compared with DM group, the relative abundance of Selenomonas spp. in DN group was significantly higher; the area under the receiver operating characteristic curve of Selenomonas spp. was 0.713 (P < 0.05). Multi-level biological identification and feature maps indicated that Selenomonas spp. might be used as a potential biomarker for DN patients. On binary logistic regression analysis, increase of Selenomonas spp. was related with DN. Conclusions We found significant between-group differences in the structural composition of oral flora. The increase in the relative abundance of Selenomonas spp. may be associated with DN in patients with chronic periodontitis.

Short-Term Impact of Multi-Cropping on Some Soil Physical Properties and Respiration

Growing as much crop biomass as possible in the shortest possible time is the target for most bio-energy producers. However, according to the requirements of the Green Deal, the consumption of fertilizers and crop protection products will have to be significantly reduced between 2023 and 2027. In order to meet all the necessary conditions for the production of biomass, a stationary field experiment was carried out at the Experimental Station of Vytautas Magnus University, Lithuania, in 2020–2021. Multi-cultivations of maize, hemp and faba bean were investigated. The aim of this study was to ascertain the impact of multi-cropping intensity on soil structural composition, stability, penetration resistance and gas concentration–respiration. As expected, multi-cropping stabilized the gas concentration and emission from the soil and decreased the proportion of micro-structures in the top soil layers. However, the stability of the soil decreased in all the experimental plots. Gas concentration and respiration mainly depended on soil structural composition, temperature and moisture content. The results of the experiment suggest performing investigations at a long-term scale because the intensive variation of meteorological conditions had a higher impact on the soil properties than the multi-cropping systems.

Changes in chemical composition of cover crops residue during decomposition

ABSTRACT: Crop residues decomposition are controlled by chemical tissue components. This study evaluated changes on plant tissue components, separated by the Van Soest partitioning method, during cover crop decomposition. The Van Soest soluble fraction was the first to be released from the crop residues, followed by cellulose and hemicellulose. Lignin was the crop residue component that suffered the least degradation, and for certain crop residue types, lignin degradation was not detected. The degradation of the main components of crop residues (soluble fraction, cellulose, hemicellulose and lignin) is determined by the chemical and structural composition of each fraction.

Identifying The Quantity of Combustion Heat when Briquetting Oil Waste Process

During the works by calculation, there were grounded the makeup of fuel briquettes, which are produced from oil wastes, coal and biomass - rice husk. Within changing considered makeups and concentration, combustion heat values calculated, which in future will allow to compare the experimental values of the fuel characteristics of the briquettes with an assigned structural composition

Crystallization and mechanical behavior of semi-crystalline polyethylene

Molecular dynamics simulations are employed to study the crystallinity and mechanical properties of multi-chain polyethylene systems. Results show that structural composition (length and number of chains) and temperature lead to different crystallinity, which are obtained by using two general measurement methods, namely chain orientation and global order. The semi-crystalline polyethylene systems are deformed under various mechanical loading modes and at different temperatures representing different polymer states. The stretching temperature and structural composition have a strong influence on the mechanical properties, including elastic modulus, yield stress and inelastic mechanisms. The orientation crystallization caused by the heat treatment stage induces a significant direction effect on the different parts of the large-strain stress-strain response. Besides, the competition of the two main inelastic deformation mechanisms, namely shear yielding and cavitation damage, are revealed during the course of stretching.

Systematic study of precursor effects on structure and oxygen reduction reaction activity of FeNC catalysts

In this work, the effect of porphyrin loading and template size is varied systematically to study its impact on the oxygen reduction reaction (ORR) activity and selectivity as followed by rotating ring disc electrode experiments in both acidic and alkaline electrolytes. The structural composition and morphology are investigated by 57 Fe Mössbauer spectroscopy, transmission electron microscopy, Raman spectroscopy and Brunauer–Emmett–Teller analysis. It is shown that with decreasing template size, specifically the ORR performance towards fuel cell application gets improved, while at constant area loading of the iron precursor (here expressed in number of porphyrin layers), the iron signature does not change much. Moreover, it is well illustrated that too large area loadings result in the formation of undesired side phases that also cause a decrease in the performance, specifically in acidic electrolyte. Thus, if the impact of morphology is the focus of research it is important to consider the area loading rather than its weight loading. At constant weight loading, beside morphology the structural composition can also change and impact the catalytic performance. This article is part of the theme issue ‘Bio-derived and bioinspired sustainable advanced materials for emerging technologies (part 2)’.