Tremendous progress has been made in the field of ferroptosis since this regulated cell death process was first named in 2012. Ferroptosis is initiated upon redox imbalance and driven by excessive phospholipid peroxidation. Levels of multiple intracellular nutrients (iron, selenium, vitamin E and coenzyme Q10) are intimately related to the cellular antioxidant system and participate in the regulation of ferroptosis. Dietary intake of monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) regulates ferroptosis by directly modifying the fatty acid composition in cell membranes. In addition, amino acids and glucose (energy stress) manipulate the ferroptosis pathway through the nutrient-sensitive kinases mechanistic target of rapamycin complex 1 (mTORC1) and AMP-activated protein kinase (AMPK). Understanding the molecular interaction between nutrient signals and ferroptosis sensors might help in the identification of the roles of ferroptosis in normal physiology and in the development of novel pharmacological targets for the treatment of ferroptosis-related diseases.

Several single nucleotide polymorphisms (SNPs) could indirectly, as well directly, influence metabolic parameters related to health effects in response to selenium (Se) supplementation. This study aimed to investigate whether the selenoprotein SNPs were associated with the response of Se status biomarkers to the Brazil nut consumption in patients using statins and if the variation in Se homoeostasis could affect antioxidant protection, lipid profile, muscle homoeostasis and selenoproteins mRNA. The study was performed in the Ribeirão Preto Medical School University Hospital. Thirty-two patients using statins received one unit of Brazil nut daily for 3 months. Body composition, blood Se concentrations, erythrocyte glutathione peroxidase (GPX) activity, total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triacylglycerol (TAG), creatine kinase (CK) activity and gene expression of GPX1 and selenoprotein P (SELENOP) were evaluated before and after Brazil nut consumption. The volunteers were genotyped for SNP in GPX1 (rs1050450) and SELENOP (rs3877899 and rs7579). SNPs in selenoproteins were not associated with plasma and erythrocyte Se, but SNPs in SELENOP influenced the response of erythrocyte GPX activity and CK activity, TAG and LDL after Brazil nut consumption. Also, Brazil nut consumption increased GPX1 mRNA expression only in subjects with rs1050450 CC genotype. SELENOP mRNA expression was significantly lower in subjects with rs7579 GG genotype before and after the intervention. Thus, SNP in SELENOP could be associated with interindividual differences in Se homeostasis after Brazil nut consumption, emphasising the involvement of genetic variability in response to Se consumption towards health maintenance and disease prevention.

Alcohol abuse causes severe metabolic abnormalities inducing hepatic damage and malnutrition. Since higher Fischer ratio proteins have therapeutic value in liver diseases, an investigation was undertaken to study the ameliorative effect of the enhanced Fischer ratio flaxseed protein hydrolysate (EFR-FPH) alone and in combination with antioxidant micronutrients on ethanol-induced hepatotoxicity in a rat model. The EFR-FPH was prepared by dual enzymatic hydrolysis and charcoal treatment of flaxseed protein. The ratio of the branched-chain:aromatic amino acids (Fischer ratio) was found to be 7·08. The EFR-FPH, characterised using LC-MS/MS, showed the abundance of free leucine and isoleucine compared with phenylalanine and tyrosine. The matrix-assisted laser desorption/ionisation-time of flight MS analysis revealed the larger peptides present in EFR-FPH with mass 2·3 kDa. The EFR-FPH improved the nutritional status, liver function and antioxidant defense in the ethanol hepatotoxicity-induced rat model. The hepatoprotective effect of EFR-FPH was significantly enhanced when combined with selenium or vitamin E. Ethanol-induced changes in the liver tissue were effectively suppressed in the groups receiving EFR-FPH. Flaxseed-based hepatoprotective dietary supplement was formulated incorporating an optimum level of EFR-FPH (10 %) based on sensory acceptability and was fortified with selenium and vitamin E. The hepatoprotective formulation significantly lowered aspartate transaminase, alanine transaminase, alkaline phosphatase and bilirubin by 47, 61, 55 and 78 %, respectively, and improved the antioxidant defense in the ethanol hepatotoxicity-induced rat model. The current investigation suggests that EFR-FPH in synergy with antioxidant micronutrients is potent in ameliorating ethanol-induced hepatotoxicity and has a potential to form a hepatoprotective dietary supplement.

Phase-change materials (PCMs) have demonstrated a wide range of potential applications ranging from electronic memories to photonic devices. These applications are enabled by the unconventional portfolio of properties that characterizes crystalline PCMs. Here, we address the origin of these unusual properties and how they are related to the application potential of these materials. Evidence will be presented that the properties are related to an unconventional bonding mechanism. Employing a novel map, which separates solids according to the number of electrons transferred and shared between adjacent atoms, it is shown that PCMs occupy a well-defined region. Depicting physical properties such as the optical dielectric constant as the third dimension in the map reveals systematic property trends. Such trends can be utilized to unravel the origins of the unconventional materials properties or alternatively, as a means to optimize them.

Thin CdTe photovoltaic device efficiencies show significant improvement with the incorporation of a CdSeTe alloy layer deposited between a MgZnO emitter and CdTe absorber. CdTe and CdSeTe/CdTe devices fabricated by close-space sublimation with a total absorber thickness of 1.5 µm are studied using microscopy measurements and show minimal diffusion of Se into the CdTe. Current loss analysis shows that the CdSeTe layer is the primary absorber in the CdSeTe/CdTe structure, and fill factor loss analysis shows that ideality-factor reduction is the dominant mechanism of fill factor loss. Improvement in the CdSeTe/CdTe absorber quality compared to CdTe is also reflected in spectral and time-resolved photoluminescence measurements. Current density vs. voltage measurements show an increase in current density of up to 2 mA/cm2 with the addition of CdSeTe due to a band gap shift from 1.5 to 1.42 eV for CdTe and CdSeTe/CdTe absorbers respectively. Voltage deficit is lower with the incorporation of the CdSeTe layer, corroborated by improved electroluminescence intensity. The addition of CdSeTe into CdTe device structures has increased device efficiencies from 14.7% to 15.6% for absorbers with a total thickness less than two microns.

The profile of the supergene zone of the Zapadno-Ozernoe massive sulphide Cu-Zn deposit differs from the classic model (Emmons, 1917) in that it includes a prominent dark sooty subzone rich in secondary sulphides. This subzone is situated above residual pyrite sands, which overlie the massive sulphide body and below quartz-baryte leached sands. It contains a diverse mineral assemblage which consists of secondary sulphides such as galena, sphalerite, metacinnabar, Se-bearing pyrite—dhzarkenite series, tiemannite, native Au, native S and native Se, and unidentified sulphosalts of Ag and Hg. The very light S isotope composition of the secondary sulphides (lowest values δ34S = —17.2‰ (VCDt) in comparison with primary pyrite ∼0‰ and baryte +18.4‰ is indicative of bacterial sulphate reduction. The overlying oxidized part of the supergene column contains minerals of the jarosite-beudantite- segnitite series. The maximum concentrations of Au, up to 150 ppm, occur in the lower part of the profile. The atypical structure, mineral assemblage and S isotope composition of the secondary sulphides in the dark layer of the supergene profile are indicative of particular geochemical conditions due to the existence of a stagnant water body that gave rise to intense bacterial activity, in turn controlled by fluctuations in the redox boundary.

Monolayers of semiconducting transitional metal dichalcogenides (TMDC) are emerging as strong candidate materials for next generation electronic and optoelectronic devices, with applications in field-effect transistors, valleytronics, and photovoltaics. Prior studies have demonstrated strong light-matter interactions in these materials, suggesting optical control of material properties as a promising route for their functionalization. However, the electronic and structural dynamics in response to electronic excitation have not yet been fully elucidated. In this work, we use non-adiabatic quantum molecular dynamics simulations based on time-dependent density functional theory to study lattice dynamics of a model TMDC monolayer of MoSe2 after electronic excitation. The simulation results show rapid, sub-picosecond lattice response, as well as finite-size effects. Understanding the sub-picosecond atomic dynamics is important for the realization of optical control of the material properties of monolayer TMDCs, which is a hopeful, straightforward tactic for functionalizing these materials.

It is known that tungsten oxide may be reacted with selenium sources to form WSe2 but literature reports include processing steps that involve high temperatures, reducing atmospheres, and/or oxidative pre-treatments of tungsten oxide. In this work, we report a non-vacuum process for the fabrication of compositionally high quality WSe2 thin films via the selenization of tungsten oxide under milder conditions. Tungsten source materials were various hydrated WO3 and WO2.9 compounds that were prepared using chemical solution techniques. Resulting films were selenized using a two-stage heating profile (250 °C for 15 minutes and 550 °C for 30 minutes) under a static argon atmosphere. Effects of the starting tungsten oxide phase on WSe2 formation after single and double selenization cycles were investigated using Raman spectroscopy and X-ray diffraction (XRD). After two selenization cycles, hydrated WO3 was converted to (002)-oriented WSe2 that exhibits well-resolved peaks for E12g and A1g phonon modes. Only a single selenization cycle was required to convert amorphous WO2.9 to WSe2. All selenizations in this work were achieved in non-reducing atmospheres and at lower temperatures and shorter times than any non-laser-assisted processes reported for WO3-to-WSe2 conversions.

In this study, we propose a Se-incorporated Ge10Sb90 as a phase-change material for phase-change memory (PCM) with high reliability and low operation power. We investigated the effect of the Se concentration on the thermal and electrical properties of Se-doped Ge10Sb90 films by varying the Se concentration from 0 to 20 at.%. The crystallization temperature, crystallization activation energy, and maximum ten-year data retention temperature increased with the increasing Se, thus demonstrating the improved thermal stability of Se-doped Ge10Sb90 films with higher Se contents. More Se also increased the rate factor, band gap, threshold voltage, and load resistance. In addition, the crystallization speed, programming window, and resistances of both the amorphous and crystalline states increased with the increasing Se concentration. In contrast, the reset current decreased with the increasing Se concentration. These results demonstrate that Se-doped Ge10Sb90 is a highly promising material for PCM applications.

Sustainable invasive weed management must address treatment effects on desired vegetation. Our objective was to determine the influence of clopyralid plus 2,4-D, glyphosate, and fosamine, at various application rates and timing, on the density and biomass of Russian knapweed and desired plant groups growing in association with this invasive weed. In a randomized complete block design with four replications, three herbicides by three herbicide rates by three herbicide application timings and a nontreated control were factorially applied to two sites located along the Missouri River riparian corridor in Montana. Clopyralid plus 2,4-D, glyphosate, and fosamine were applied during the spring rosette stage of Russian knapweed (June), the bud to bloom stage of Russian knapweed (July), or the flowering stage of Russian knapweed (August). Herbicide rates were considered low, medium, and high based on label rates of clopyralid plus 2,4-D, glyphosate, or fosamine. Density and biomass of all species were sampled 3 yr after treatment. Russian knapweed biomass decreased from 125 to about 25 g/m2 using clopyralid plus 2,4-D, irrespective of rate or timing of application. Russian knapweed density was reduced by about half by this mixture of herbicides. Nonnative grass density and biomass were maintained, whereas native grasses increased using clopyralid plus 2,4-D at medium or high rates. Neither glyphosate nor fosamine provided substantial Russian knapweed control or increases in grasses. Too few forbs were present to analyze their response to the treatments. We believe that herbicides must be combined with revegetation in areas lacking a diverse mixture of desired species capable of capturing resources made available by controlling Russian knapweed.

Se supplementation in feed can be used to increase human Se intake, and this has showed significant progress in the area of healthy nutrition in recent years. It has been proven that the antioxidant function of Se is likely to contribute to better shelf life in animal products. Egg freshness can be monitored by assessment of albumen and yolk pH, fatty acid profile, malondialdehyde content, yolk vitelline membrane strength, carbonyl content and yolk pigment stability. It has been proven that Se reduces oxidation processes inside the egg and hence the pH of its contents does not increase too rapidly when stored. Several studies have reported that the rate of fatty acid oxidation and the production of lipid oxidation products (malondialdehyde, MDA) are lower in Se enriched eggs compared to non-enriched eggs. These results have been explained by an increase in gluthation peroxidase (GSH-Px) levels and activity in eggs after supplementation of laying hens with Se, which is an essential component of GSH-Px. Se has a positive effect on the stability of yolk pigments, which is linked to the oxidation stability of yolk lipids. According to several studies, Se decreases the carbonyl, which is a marker of protein oxidation. The yolk vitelline membrane consists of a high amount of protein incorporating Se, which explains the increased vitelline membrane strength after Se supplementation.

The photo-structural changes in a 2 μm thick amorphous selenium (a-Se) thin film, thermally evaporated on Si substrate, have been studied by micro-Raman spectrometer with 532 nm laser at different laser power densities (1 to 64 W/mm2) and exposure times (15 – 60 s). In addition, the nanoscale photo-structural changes/photo-thermodynamic phase changes are examined on 90 nm a-Se film coated on SiO2 cladding of the optical Fiber Bragg Grating (FBG) sensor on prolonged exposure to a low power (1 mW/mm2, 10 mW/mm2) 532 nm laser, which is measured by means of photo-striction (light induced strain) in the material.

Integrated safety assessment methodology that analyzes radionuclide migration reflecting the spatial and temporal changes of disposal systems was developed for a geological disposal site with uplift and denudation, and then some case analyses for an assumed site were carried out. The combination of uniform uplift and denudation has the largest effect on the radionuclide migration because the ground water flow velocity increases with decreasing depth from the ground surface. In the case without denudation, tilted uplift has more effect than uniform uplift because flow velocity in tilted uplift increases with increasing hydraulic gradient. The long-term change of the geological structures including the uplift and denudation, the hydraulic conditions, and the recharge and outlet of the ground water around a candidate site should be carefully investigated to determine the appropriate the place, depth and layout of the repository.

Selenium (Se) is an important element for assessing the safety of high-level waste disposal. Se is redox-sensitive, and its oxidation state varies from -2 to 6 depending on the redox conditions and pH of the solution. Large quantities of ferrous ions formed in bentonite due to corrosion of carbon steel overpack after the closure of a repository are expected to maintain a reducing environment near the repository. Therefore, the migration behavior of Se in the presence of Fe in bentonite was investigated by electrochemical experiments. Na2SeO3 solution was used as tracer solution. Dry density range of bentonite was from 0.8 to 1.4 ×103 kg/m3.

Results indicated that Se was strongly retained by the processes such as precipitation reaction with ferrous ions in bentonite. Se K-edge X-ray absorption near-edge structure (XANES) measurements were performed at the BL-11 beamline at SAGA Light Source, and the results revealed that the oxidation state of Se in the bentonite remained Se(IV).

Bacterial infections are commonly found on paper towels and other paper products leading to the potential spread of bacteria and consequent health concerns. The objective of this in vitro study was to introduce antibacterial properties to paper towel surfaces by coating them with selenium nanoparticles. Results showed that the selenium nanoparticle coated paper towels inhibited the growth of S. Aureus and P. aeruginosa by 80%∼90% after 72 hours compared with the uncoated paper towels. Thus, the study showed that nano-selenium coated paper towels may lead to an increased eradication of bacteria to more effectively clean a wide-range of clinical environments, thus, improving health.

In this work, the synthesis of two amphiphilic π-conjugated compounds such as ferrocenylthioamide and ferrocenylselenoamide, with the general formula FcC=MNH(CH2)15CH3 with M = S or Se, are reported. The ferrocenyl group is a donor moiety forming a π-conjugated system with the amides of sulfur and selenium; both elements have also bioactivity with pharmacological interest. These two compounds formed Langmuir (L) monolayers at the air-water interface, which were characterized by isotherms of surface pressure versus molecular area (π-A) and compression/expansion cycles (hysteresis curves); Brewster angle microscopic images were also obtained. By using the Langmuir-Blodgett method molecular monolayers were transferred onto glass substrates. These nanostructures, in form of Langmuir-Blodgett (LB) films, were characterized through atomic force microscopy (AFM).

Papers in the Appendix were published in electronic format as Volume 1534

Bacterial infections are commonly found on paper towels and other paper products leading to the potential spread of bacteria and consequent health concerns. The objective of this in vitro study was to introduce antibacterial properties to paper towel surfaces by coating them with selenium nanoparticles. Scanning electron microscopy was used to measure the size and distribution of the selenium coatings on the paper towels. Atomic force microscopy was used to measure the surface roughness of paper towels before and after coated with selenium nanoparticles. The amount of selenium precipitated on the paper towels was measured by atomic absorption spectroscopy. In vitro bacterial studies with Staphylococcus aureus were conducted to assess the effectiveness of the selenium coating at inhibiting bacterial growth. Results showed that the selenium nanoparticles coated on the paper towel surface were well distributed and semispherical about 50nm in diameter. Most importantly, the selenium nanoparticle coated paper towels inhibited S. aureus growth by 90% after 24 hours and 72 hours compared with the uncoated paper towels. Thus, the study showed that nano-selenium coated paper towels may lead to an increased eradication of bacteria to more effectively clean a wide-range of clinical environments, thus, improving health.

Moore’s law of transistor scaling, the exponential increase in the number of complementary metal oxide semiconductor (CMOS) transistors per unit area, continues unabated; however, computer clock speeds have remained frozen since 2003. The development of a new digital switch, the piezoelectronic transistor (PET), is designed to circumvent the speed and power limitations of the CMOS transistor. The PET operates on a novel principle: an electrical input is transduced into an acoustic pulse by a piezoelectric element which, in turn, is used to drive a continuous insulator-to-metal transition in a piezoresistive element, thus switching on the device. Performance is enabled by the use of key high response materials, a relaxor piezoelectric, and a rare-earth chalcogenide piezoresistor. Theory and simulation predict, using bulk material properties, that PETs can operate at one-tenth the present voltage of CMOS technology and consuming 100 times less power while running at multi-GHz clock speeds. A program to fabricate prototype PET devices is under way.

Biofilms are a common cause of persistent infections on medical devices as they are easy to form and hard to treat. Selenium and its compounds are considered to be a novel material for a wide range of applications including anticancer applications and antibacterial applications. The objective of this study was to coat selenium nanoparticles on the surface of polycarbonate medical devices and examine their effectiveness at preventing biofilm formation. The results of this in vitro study showed that the selenium coating significantly inhibited Staphylococcus aureus growth on the surface of polycarbonate after 24 hours. Thus, this study suggests that coating polymers with nanostructured selenium is a fast and effective way to reduce bacteria functions leading to medical device infections.