Temporal Variability of Urinary Phthalate Metabolite Levels in Men of Reproductive Age

Phthalates are a family of multifunctional chemicals widely used in personal care and other consumer products. The ubiquitous use of phthalates results in human exposure through multiple sources and routes, including dietary ingestion, dermal absorption, inhalation, and parenteral exposure from medical devices containing phthalates. We explored the temporal variability over 3 months in urinary phthalate metabolite levels among 11 men who collected up to nine urine samples each during this time period. Eight phthalate metabolites were measured by solid-phase extraction–high-performance liquid chromatography–tandem mass spectrometry. Statistical analyses were performed to determine the between- and within-subject variance apportionment, and the sensitivity and specificity of a single urine sample to classify a subject’s 3-month average exposure. Five of the eight phthalates were frequently detected. Monoethyl phthalate (MEP) was detected in 100% of samples; monobutyl phthalate, monobenzyl phthalate, mono-2-ethylhexyl phthalate (MEHP), and monomethyl phthalate were detected in > 90% of samples. Although we found both substantial day-to-day and month-to-month variability in each individual’s urinary phthalate metabolite levels, a single urine sample was moderately predictive of each subject’s exposure over 3 months. The sensitivities ranged from 0.56 to 0.74. Both the degree of between- and within-subject variance and the predictive ability of a single urine sample differed among phthalate metabolites. In particular, a single urine sample was most predictive for MEP and least predictive for MEHP. These results suggest that the most efficient exposure assessment strategy for a particular study may depend on the phthalates of interest

Examining the Impact of Patch Burning on Livestock Grazing Patterns in Edwards Plateau, Texas

Production of sheep, goat, and cattle are major agricultural enterprises on West Texas rangelands, especially in the Edwards Plateau. In this region, the use of fire as a management tool was suppressed until recently. Although previous studies have been conducted to evaluate cattle use of burned versus unburned patches, there has been a lack of studies where combinations of livestock species grazing together on patch burned areas have been evaluated. The objective of this study is to examine grazing patterns of cattle, sheep and goats, both spatially and temporally, on areas where patch burning has been implemented. The study site is the Texas A&M AgriLife Research Ranch, Martin Ranch, located in Mesquite-Oak-Savanna ecosystem in Menard County of Texas, USA. In February 2019 and September 2020, patch burns were implemented on the ranch and represented about 29% of the total ranch area (480 out of 1655 ha). After the burns, animals from the resident herd were randomly selected and GPS collars were placed on 34 goats, 33 sheep, and 8 cows to reflect the proportion of animals in the resident herd. The GPS collars were set to collect movement data every 10 minutes during a fourteen-month period. Gates and fences for the entire ranch were opened and livestock were free to choose areas to graze. Data from the GPS’s were evaluated to determine locations where the animals grazed and their preferences for different areas of the landscape. Initial observations indicate that cattle and sheep were more attracted by recent burned patches compared to goats. Livestock forage use patterns and time spent by species in the burned and unburned areas and among different vegetation land cover classes are presented. Information from this study will assist in providing information to producers on how implementation of patch burning would influence their management of these grazing lands

Государственное регулирование электроэнергетики

Цель работы – разработка теоретических и практических положений, направленных на совершенствование механизмов государственного регулирования электроэнергетики в России, выявление основных тенденций и возможных путей дальнейшего развития названной сферы в российской экономике. Объектом исследования являются отношения, возникающие в процессе осуществления государственного регулирования электроэнергетической отрасли в России.Purpose - to develop theoretical and practical provisions aimed at improving the mechanisms of state regulation of electric power industry in Russia, identifying the main trends and opportunities for further development of the said spheres of the Russian economy. The object of the study are the relations arising in the implementation of state regulation of electric power industry in Russia

How Metal/Insulator Interfaces Enable the Enhancement of the Hydrogen Evolution Reaction Kinetics in Two Ways

Laterally nanostructured surfaces give rise to a new dimension of understanding and improving electrochemical reactions. In this study, we present a peculiar mechanism appearing at a metal/insulator interface, which can significantly enhance the Hydrogen Evolution Reaction (HER) from water reduction by altering the local reaction conditions in two ways: facilitated adsorption of hydrogen on the metal catalyst surface and improved transfer of ions through the double layer. The mechanism is uncovered using electrodes consisting of well-defined nanometer-sized metal arrays (Au, Cu, Pt) embedded in an insulator layer (silicon nitride), varying various parameters of both the electrode (size of the metal patches, catalyst material) and the electrolyte (cationic species, cation concentration, pH). In addition, simulations of the electrochemical double layer are carried out, which support the elaborated mechanism. Knowledge of this mechanism will enable new design principles for novel composite electrocatalytic systems

Phase I/II study of the anti-oestrogen zindoxifene (D16726) in the treatment of advanced breast cancer. A Cancer Research Campaign Phase I/II Clinical Trials Committee study.

We report a phase I/II study of the indole derivative, zindoxifene, an anti-oestrogen with intrinsic oestrogenic activity. We have treated 28 women with advanced breast cancer of whom 26 had received prior endocrine therapy. Oral zindoxifene doses ranged from 10 to 100 mg daily; doses were escalated in some patients. Twenty-five patients were assessed for response; the remaining three patients completed less than 3 weeks of treatment. There were no objective responses; disease stabilised in seven patients for up to 5 months and progressed in the remaining 18. Five patients (including three treated with tamoxifen) responded to subsequent endocrine therapy. Nausea, which was dose-limiting, affected half of the patients treated with 80 mg daily. Metabolites of zindoxifene were detectable in serum at all doses used, and sex hormone binding globulin (SHBG) levels showed a strong tendency to rise at the higher doses, indicating that zindoxifene is absorbed and has biological activity. We conclude that zindoxifene in the doses used in this study has only marginal therapeutic activity in the treatment of advanced breast cancer