Land use and occupation and pesticide contamination assessment in honey from Africanized honey bees (Hymenoptera: Apidae) using gas chromatography-mass spectrometry.

We examined pesticide contamination in honey from Africanized honey bees in two different seasons, and evaluated the concentration and incidence of these compounds in georeferenced apiaries to provide relevant information for food safety and environmental quality. The land use and occupation of the region were evaluated by selecting 15 apiaries and georeferencing three randomly selected colonies of Africanized honey bees within each apiary. Honey samples were collected during two seasons, and three organochlorine pesticides (p.

Reactivity assessment of oligomeric systems associated with crystalline and amorphous cellulose for bioethanol production: a DFT study.

Context: The production of bioethanol from renewable raw materials is a decisive factor in the economic development of many countries. However, the complexity of the processes and the numerous experimental variables involved require a deeper understanding of the chemical reactions that take place during bioethanol production to define optimal parameters. Here, we have employed density functional theory-based calculations to investigate the local reactivity of oligomeric systems by considering crystalline and amorphous cellulose models to better understand some details regarding pulp pretreatment processes.

Impact of Silicon Carbide Coating and Nanotube Diameter on the Antibacterial Properties of Nanostructured Titanium Surfaces.

This study aimed to comprehensively assess the influence of the nanotube diameter and the presence of a silicon carbide (SiC) coating on microbial proliferation on nanostructured titanium surfaces. An experiment used 72 anodized titanium sheets with varying nanotube diameters of 50 and 100 nm. These sheets were divided into four groups: non-coated 50 nm titanium nanotubes, SiC-coated 50 nm titanium nanotubes, non-coated 100 nm titanium nanotubes, and SiC-coated 100 nm titanium nanotubes, totaling 36 samples per group.

Decreasing global tropical cyclone frequency in CMIP6 historical simulations.

The impact of anthropogenic global warming on tropical cyclone (TC) frequency remains a challenging issue, partly due to a relatively short period of reliable observational TC records and inconsistencies in climate model simulations. Using TC detection from 20 CMIP6 historical simulations, we show that the majority (75%) of these models show a decrease in global-scale TC frequency from 1850 to 2014. We demonstrated that this result is largely explained by weakened mid-tropospheric upward motion in CMIP6 models over the Pacific and Atlantic main development regions.

Identification of Iodotyrosines as Novel Substrates for the Thyroid Hormone Transporter MCT8.

Monocarboxylate transporter 8 (MCT8) is the most specific thyroid hormone transporter identified to date, deficiency of which has been associated with severe intellectual and motor disability and abnormal serum thyroid function tests. However, it is presently unknown if MCT8, similar to other thyroid hormone transporters, also accepts additional substrates, and if disruption of their transport may contribute to the observed phenotype. In this study, we aimed to identify such substrates by applying liquid chromatography-mass spectrometry-based metabolome analysis in lysates of control and MCT8-overexpressing oocytes.