Higher Activity Content Research Articles

Determination of the Distribution of Gamma Emitting Radionuclides in Abeokuta using an In-Situ Gamma Spectrometric System

In all ground formations, naturally occurring radionuclides, such as 40K, 226Ra and 232Th and their decay products exist as trace levels. In this study, in-situ gamma spectrometry, which consists of a NaI(Tl) detector, a portable shield 4 cm thick and 17.5 cm deep which was filled with lead shots and a mobile stand has been used to measure different components of environmental radioactivity around Abeokuta, capital of Ogun State, Southwestern Nigeria. Results from the study shows that 40K, 226Ra and 232Th has a mean of 469.28 ± 4.09, 65.11± 0.27 and 558.93 ± 6.61 Bq/kg correspondingly. Calculated values for absorbed dose rate are as follows: 451.27 nGy/h for the mean, 86.76 nGy/h for the lowest, and 1635.92 nGy/h for the highest. The mean value of the yearly effective dosage is 0.99 mSv/y, with low value of 0.22 mSv/y and high value of 4.22 mSv/y. The minimum value exceeds the maximum value. Based on the findings of this investigation, one may draw the conclusion that the comparatively high activity concentration level of the city can be attributed to the unexpectedly high concentrations that were found at some sites.

Chronic Radium-226 Bioaccumulation and Toxicity in the Aquatic Invertebrate Daphnia magna.

Mining operations in Canada, including uranium mining and milling, generate by-products containing radionuclides, including radium-226 (226Ra), a long-lived, bioaccumulative calcium (Ca2+) analog. Despite strict discharge regulations, there is limited evidence to suggest that current thresholds for 226Ra adequately protect aquatic organisms. Furthermore, Canada lacks a federal water quality guideline for 226Ra, underscoring the need for protective limits to safeguard aquatic ecosystems. Hence, this research aimed to generate data on 226Ra toxicity to the model aquatic invertebrate Daphnia magna. For this purpose, two 21-day chronic toxicity tests with D. magna were conducted, with survival and reproduction as the endpoints, as well as a reduced water hardness experiment, a multigenerational study, and a bioaccumulation assay. These experiments demonstrated that a high activity concentration (nominal 50Bq/L) of 226Ra can significantly impact the survival of D. magna. 226Ra was also found to bioaccumulate in D. magna with a BAF of 72.8. Since the Canadian Metal and Diamond Mining Effluent Regulations (MDMER) monthly mean effluent limit is currently set at 0.37Bq 226Ra /L, the limit for composite samples at 0.74Bq/L 226Ra, andthe limit for grab samples at 1.11Bq/L 226Ra, it is unlikely that toxic effects to aquatic cladocerans like D. magna from 226Ra will be observed downstream of Canadian mines and mills.

Anti-seepage reinforcement property and pollution control effect of bio-cemented fracture zone in electrolytic manganese residue dump

The heavy metal (HM) pollutants in electrolytic manganese residue (EMR) can easily diffuse through the seepage channel of the dump under the leaching action of rainfall. Particularly, the fracture zone, as one of the widely distributed seepage channels in the manganese residue dump (MRD), poses a greater threat to the ecological environment due to its weak mechanical properties, strong ductility, and numerous fractures. In this study, the microbially induced calcium carbonate precipitation (MICP) method was used for anti-seepage reinforcement of the fracture zone in an MRD to be constructed. The optimal conditions for the anti-seepage reinforcement of the fracture zone using the MICP method were proposed, and the control effect of the bio-cemented fracture zone on the major HM pollutant in the leachate of EMR was illustrated. Results showed that after grouting at a rate of 3 mL/min for 12 cycles with a grouting slurry of high urease activity (9 mM urea/min) and high cementation solution concentration (1.5 mol/L), the permeability coefficient of the fracture zone decreased from 10−4 to 10−5, and the unconfined compressive strength was approximately 5.58 times that of uncemented. Furthermore, the cubic calcite crystal clusters with high purity, good stability, dense arrangement, and high cementation properties were generated using the optimal conditions, and the pores were transformed from long columnar to spherical pores. Additionally, the Mn2+ concentration in the effluent from the fracture zone at the stabilization stage was only 663 mg/L, significantly lower than that of the leachate of EMR, and the risk of leaching changed from very high risk to low risk. The research outcomes can provide guidance and reference for laboratory model testing and in-situ testing of bio-cemented fracture zone, and it is expected to provide the theoretical and technological support for green and economic anti-seepage reinforcement of the fracture zone.

Detection and quantification of small and low-uptake lesions for differentiated thyroid carcinoma using non-time-of-flight iodine-124 PET/MRI.

124-iodine (124I) is used for positron emission tomography (PET) diagnostics and therapy planning in patients with differentiated thyroid cancer (DTC). Small lesion sizes(<10mm) and low 124I uptake are challenging conditions for the detection of DTC lymph node lesions. The aim of this study was to systematically investigate the lesion detectability and quantification performance under clinically challenging imaging conditions using non-time-of-flight (TOF) PET/magnetic resonance imaging (MRI) in the clinical context of radionuclide therapy planning of DTC patients. PET/MR measurements were performed on the Siemens Biograph mMR using a small lesion NEMA-like phantom (six glass spheres, diameters 3.7-9.7mm). 60 min list-mode data were acquired for nine activity concentrations (AC) ranging from 25kBq/mL to 0.25kBq/mL using a sphere-to-background ratio of 20:1. PET list-mode data were divided into five timeframes (60, 30, 16, 8, and 4min) and reconstructed using either ordered-subsets expectation maximization (OSEM) or OSEM+ point spread function (PSF) algorithm. For all reconstructions, the smallest detectable sphere size was investigated in a human observer study. Partial volume effect (PVE) corrected PET images (contour and oversize-based approach) were analyzed considering a±30% deviation range between imaged and true AC as acceptable. Clinical data of eight DTC patients with small lymph node lesions were evaluated to assess agreement between the PVE correction approaches. Longer PET acquisition times, higher ACs, and PSF reconstructions resulted in improved PET image quality and overall improved lesion detectability. The smallest 3.7mm sphere was only visible under the best imaging conditions. Using a typical clinical 124I whole-body PET/MRI protocol with an acquisition time of 8 min using OSEM reconstructions, all lesions of ≥6.5mm in diameter could be detected and the quantification provided reliable results approximately above 5.0kBq/mL. An accurate quantification of ACs in the 4.8mm sphere was not feasible in this study. In the clinical evaluation of 10 lesions, a good agreement between oversize- and contour-based PVE corrections was observed(<15% deviation). The results showed that a reliable quantification of 124I uptake with PET/MRI is feasible and, therefore, could be used to perform radioiodine pre-therapy lesion dosimetry and individualized therapy planning in DTC patients.

Low Temperature Epitaxy Processes for Contact Resistivity Reduction

With the continued scaling of CMOS logic devices the contact resistivity at the semiconductor/silicide interface has become a limiting factor for device performance. High active dopant concentration at this interface is critical to realizing low contact resistance, and ion implantation is conventionally used to achieve this. We have previously reported [1] that contact cavity shaping to increase the contact area can be used to decrease the contact resistivity. This etching process produces convex (111) facets from a (100) starting surface in the source-drain volume, thereby increasing the contact area. The etched-recess shape can be varied from a “U” to a “V” as seen in figures 1(b) through (d). The ρc for these shapes was measured after integrating a 385°C SiGe:B in the recessed layer on TLM structures decreases with increasing (111) facet-length and for the longest facet length a ρc = 8.0 x10-10 Ωcm-2, where the implant + anneal control sample had ρc = 1.5x10-9 Ωcm-2. On FinFET structures the cavity shaping + low temp SiGe:B achieved a ρc = 5.2 x10-10 Ωcm-2 compared to the implant + anneal control of ρc = 1.5x10-9 Ωcm-2 as shown in figures 1(e) and (f).Cavity shaping can be a helpful knob to improve contact resistance, however thermal budget and integration constraints necessitate that the epitaxial growth of these layers are at temperatures ≤ 400°C. These low growth temperatures can be beneficial to dopant activation, however the growth rate and selectivity are negatively impacted. Next generation contact epitaxy processes will integrate etch cavity shaping with novel deposition chemistries to surmount these challenges. For PMOS SiGe:B deposition acceptable growth rates are more easily realized due to the intrinsic growth rate benefit from Ge and B incorporation, as well as the higher reactivity of Ge precursors compared to their Si analogs. However maintaining selective deposition requires large flows of HCl which decrease the growth rate and the boron concentration. We have employed an alternative Cl-containing precursor to maintain selectivity during Si0.5Ge0.5:B deposition at temperatures as low as 350°C, with a growth rate of 13 Å/min. Whereas to achieve selectivity with HCl at this temperature results in a growth rate of 6 Å/min. Figures 2(a) through (d) show a patterned wafer images with and without the addition of this precursor at 350°C.The situation for NMOS Si:P deposition is more difficult, as PH3 does not increase the growth rate as drastically as GeH4 or B2H6 do, and the gas-phase reactivity of conventional Si-hydrides and hydrochlorides is quite low. Higher-order silanes such as Si3H8 and Si4H10 can be used however the cost of these precursors is high and their efficiency at 400°C is typically between 0.01% and 1%. Ideally a phosphorus doping precursor, which is ostensibly used at lower flow rates, could enhance the growth rate similar to the effect of B2H6 in the growth of p-type materials. The other major concern for low temperature Si:P deposition processes is the selectivity to dielectric surfaces. A fully selective process in unlikely for Si:P at these temperatures and etch-back cycles will be required to remove the materials which nucleate on the dielectric surfaces. It is therefore desired to identify a P precursor with higher intrinsic selectivity than Si2H6-PH3 and/or Si3H8-PH3 processes.Here we present a Si2H6-based process in which the P dopant precursor (PDOP-1) is engineered to enhance the epitaxial growth rate and delay the nucleation of material on the dielectric surface. Figure 3(a) compares the growth rate vs. temperature for a Si2H6-PH3 process and Si2H6-PDOP-1. The growth rate of the PH3 process falls-off rapidly below 400°C, whereas a measurable epitaxial growth rate is maintained down to ~ 385°C in the PDOP-1 process. We find that for equivalent growth conditions and %P that PDOP-1 can increase the growth rate by 60-80% relative to PH3 processes. In figure 3(b) the amorphous growth rate on SiO2 is plotted vs time for a Si2H6-PH3 benchmark and Si2H6-PDOP. From this plot we have determined a nucleation delay of ~ 90 seconds for PDOP-1, whereas the benchmark PH3 does not exhibit a nucleation delay. This behavior is further explored in figure 4 where we have deposited SiP non-selectively on a simple patterned wafer using Si2H6-PH3, Si3H8-PH3, and Si2H6-PDOP1. We have used the epi to amorphous thickness ratio as metric for the intrinsic selectivity of each process. Based on these results the intrinsic selectivity is improved to 4:1 using PDOP-1, from 2:1 and 3:1 for the, Si3H8-PH3 and Si2H6-PH3 benchmarks, respectively.[1] N. Breil et. al. IEEE Symposium on VLSI Technology, 2023 Figure 1

(Invited) Boron δ-Doping and Silicon Epitaxy on Chlorinated Silicon Surfaces

The halogen-silicon system has been well-studied over the years due to the prevalent use of halogen-based plasmas for silicon device processing and for its role in fostering chemical reactions leading to the functionalization of silicon surfaces. Most recently, our work has demonstrated the effectiveness of a single monatomic layer of chlorine to resist the adsorption of chlorinated molecular dopant precursor gases and support the epitaxial growth of silicon from a molecular beam source. We have leveraged these findings to realize atomic-scale quantum devices in which we are able to confine dopant atoms to atomically-precise regions of a nominal single plane of silicon with sufficient density to support ohmic conduction across these structures at mK temperatures. Here, I will discuss our process of using BCl3 to obtain single layers of heavily boron-doped silicon with an extremely high active carrier concentration (> 1014 cm-2), as well as the role of the chlorinated silicon surface in supporting the growth of high quality, epitaxial silicon capping layers.

Kinetic Analysis of Lithium Titanium Oxide by Applying the Diluted Electrode Method to Various Electrochemical Measurements

Elucidating the diffusion phenomenon of Li ions in lithium insertion electrodes used in lithium-ion batteries is important for improving power capability of the batteries. However, it is extremely difficult to identify the rate-determining process of the reaction because there are various mass transport processes in the lithium insertion electrode. In our laboratory, by using a diluted electrode in which part of the active material is replaced with an electrochemically inactive material, the rate-determining step can be controlled by varying the active material content; the rate-determining step is Li-ion diffusion in the electrolyte within electrode pore for the conventional electrode with high active material content versus Li-ion transportation in the solid active material for the diluted electrode with quite low content. Thus, we have succeeded in measuring the inherent electrochemical properties of lithium insertion material via diluted electrode method.In this study, we applied this diluted electrode method to various electrochemical measurements such as chronopotentiometry, chronoamperometry, and cyclic voltammetry, and analyzed the results in a complementary manner to understand the electrode kinetics of lithium insertion electrodes. In the experiment, lithium titanium oxide (Li[Li1/3Ti5/3]O4; LTO) was used as the active material and aluminum oxide (Al2O3) as the inactive material. The diluted LTO electrode consisted of (LTO+Al2O3):AB:PVdF = 88:6:6.According to the results on chronopotentiometry (Fig. a), the capacity retention in the oxidation reaction was significantly higher than that in the reduction reaction. This means that the inherent reaction kinetics of LTO is asymmetric between oxidation and reduction. Chronoamperometric results at various applied voltages (Fig. b) also showed that the capacity increased more rapidly in the oxidation reaction than in the reduction reaction at the diluted LTO electrode. In the cyclic voltammograms of the diluted LTO electrode (Fig. c), the oxidation and reduction peaks were symmetrical, suggesting that there was almost no difference in reaction rate between the oxidation and reduction reactions.In this presentation, we will analyze these measurement results using equations related to diffusion phenomena (Cottrell equation, Sand equation, etc.), and compare the independently obtained kinetic parameters from each measurement, we will discuss the validity of applying these analytical formulas to lithium insertion electrodes. Figure 1

Evaluation of radiological hazards associated with some Egyptian marble and granite rocks

The aim of the current study is to evaluate the radioactivity estimate the radiological risk of some granites and marbles rocks and explaining the cause of increased radioactivity in some types of rocks. The radioactivity of some granites and marbles produced in Egypt were determined by using a Germanium detector. Three types of marble (Breshia, Galala, and Trista) and three types of granite (Gandola, White Halayeb, and Red Aswani) were collected. All marble samples show low radioactivity with average activity concentrations of 20 ± 2, 4.50 ± 0.5, and 6.70 ± 1.2 Bqkg− 1 for 226Ra, 232Th, and 40K respectively. Granite samples have higher activity concentration with averages of 152 ± 7, 129 ± 8, and 1228 ± 15 Bqkg− 1 for 226Ra, 232Th, and 40K respectively which exceed the world average values of soil (32,45,412 Bqkg− 1 for 226Ra, 232Th, and 40K respectively) excluding Granite G.2 (white Halayeb) as it shows an insignificant level of radioactivity. The annual effective doses of marble samples Breshia, Galala, and Trista were measured to be 4.42 ± 0.4; 158 ± 14 and 153 ± 15 µSvy− 1, and 1008 ± 147, 80 ± 7 and 987 ± 45.0 µSvy− 1 for the granite samples Gandola, White Halayeb and Red Aswani respectively. The radiation hazard parameters show a higher value for granite samples than marble samples, primarily due to the presence of potassium feldspar minerals in these types of granites. marbles were observed to be radiologically safer than granite because they possess a neglected 40K content and a trace quantity of uranium and thorium. Moreover, the minimum potassium content is enough to make a rock radiological unsafe due to 40K only being determined to be about 13.2%.

Amorphous Nanobelts for Efficient Electrocatalytic Ammonia Production

AbstractOne‐dimensional (1D) amorphous nanomaterials combine the advantages of high active site concentration of amorphous structure, high specific surface area and efficient charge transfer of 1D materials, so they present promising opportunities for catalysis. However, how to achievie the balance between the high orientation of 1D morphology and the isotropy of amorphous structure is a significant challenge, which severely obstructs the controllable preparation of 1D amorphous materials. Guided by the hard‐soft acids‐bases theory, here we develop a general strategy for preparing 1D amorphous nanomaterials through the precise modulation of bond strength between metal ions and organic ligands for a moderated fastness. The soft base dodecanethiol (DT) is multifunctionally served as both structure‐regulating agent and morphology‐directing agent. Compared with the borderline acids (e.g. Fe2+, Co2+, Ni2+) to construct amorphous structure, soft acid of Cu+ which produced crystalline nanobelts can still be amorphized by reducing the hardness of Cu ions through redox reaction to weak Cu−SR bond. Due to the combined advantages of amorphous structure and one‐dimensional morphology, amorphous CuDT nanobelts exhibited excellent electrocatalytic activity in electrochemical nitrate reduction, outperformed most of the reported Cu‐based catalysts. This work will effectively bridge the gap between traditional 1D crystalline nanomaterials synthesis and their amorphization preparation.

Facile construction of superhydrophobic porous red mud/slag-based geopolymer for thermal insulation and oil/water separation

Red mud (RM) is difficult to be comprehensively utilized and has a serious impact on the environment due to the high alkalinity, low activity, and high content of harmful substances. In this study, porous RM-based geopolymers (PRGMs) with high porosity ratio (76.83%) and compressive strength (1.16 MPa) were prepared by controlling the ratio of slag and RM (60%) and curing temperature (70 °C) and adding a mechanical foaming agent (MFA: 12%). The flux of the PRGMs was as high as 10180.33 L·m-2·h-1 at a thickness of 3 mm. The equilibrium cold surface temperature was reduced from 175.6 to 131.7 °C compared to a structure without MFA. In addition, a superhydrophobic PRGMs (SPRGMs) was successfully modified by chemical vapor deposition using water and polymethylhydrosiloxane at 120 °C for 3 h. It had excellent superhydrophobic properties (159.04°) and low thermal conductivity (0.1922 W·m⁻1·K⁻1). The contact angle of the SPRGMs was still >150° even after treatment under real simulation conditions including acid/alkali/salt solution contact/immersion, variable temperature (-20 to 450 °C for 2 h), ultraviolet aging (60 h), and physical abrasion (10 cycles). The SPRGMs achieved 100% desorption of light/heavy oils with excellent and stable cycling performances. The contact angle was still larger than 151° after 10 cycles. Furthermore, the SPRGMs are effective for a continuous treatment of oil/water emulsions and mixtures by gravity, which provides a new concept for the development of thermal insulation building materials, large-scale treatment of RM, and industrial treatment of oil/water pollution.

The Antileishmanial, Antioxidant and Cytotoxic Potential of Cecropia concolor Willd (Urticaceae), an Amazonian Species

Cecropia sp. (Urticaceae) are commonly used in traditional medicine in South American countries for the treatment of different diseases. To date, the species Cecropia concolor Willd, of Amazonian occurrence, has not been investigated for its pharmacological potential. In this study, we described the chemical profile and the antileishmanial, antioxidant and cytotoxic activities of extracts of the leaves of C. concolor. The ethanolic extract and its partition phases (hexane, ethyl acetate and hydroethanolic) were analyzed for their chemical classes and phenolic content. Antileishmanial activity was assessed against Leishmania (L.) amazonensis. The antioxidant activity was evaluated using the DPPH method and in MRC-5 human fibroblast cells. Toxicity was tested against Artemia salina and in human cells (fibroblasts and cancer lines). The leaves of C. concolor have phenolic substances, such as flavonoids, as well as terpenes, steroids and alkaloids. Chlorogenic acid, caffeic acid, schaftoside and vicenin 2 were identified. The hydroethanolic phase showed a high concentration of phenolic compounds and pronounced antioxidant activity. The antileishmanial activity was observed in the ethanolic extract, with a promising effect of the hexane phase. The C. concolor ethanolic extract and its phases are non-toxic, which makes this species of interest in pharmaceutical and cosmetics applications.

A comparative study of the elevated radioactivity in beach placer deposits of Bangladesh.

Beach sediments are mineral deposits formed through weathering and erosion of either igneous or metamorphic rocks. Among the rock constituent minerals are some natural radionuclides that contribute to ionizing radiation exposure on Earth. Kolatoli and Kuakata are the two major beaches with heavy mineral deposits and important tourist sites in Bangladesh. Natural radioactivity in Kolatoli and Kuakata beach sand deposits along the southern coast of Bangladesh was assessed and compared to identify the sources, causes, and possible environmental impact. Result shows most of the radionuclides have higher activity concentrations than the background level, and the activity varies with the sample locations. The dominant radionuclides were found to be the radionuclides of thorium series i.e. Th-232 and Ra-228 followed by uranium series and K-40. The radioactivity in Kolatoli beach sands was observed to be much higher than Kuakata beach due to the presence of a higher content of heavy minerals i.e. illmenite, rutile, zircon, garnet and monazite. Furthermore, monazite and zircon are the two radioactive minerals that are considered to be the main contributors to the radioactivity in Kolatoli beach sand. These minerals are dominated by the activity of thorium series radionuclides i.e. Th-232 and Ra-228 surpass the activity of all other radionuclides such as U-238, U-234, Th-230, Ra-226, Po-210, and K-40. However, major contribution of radioactivity in Kuakata beach sand comes from uranium series radionuclides such as U-238, U-234, Ra-226, and Po-210. Beach morphology, sedimentological, and geochemical evolution of those minerals might be important areas of further study for the radioactivity monitoring activity in those areas.

Amorphous Nanobelts for Efficient Electrocatalytic Ammonia Production.

One-dimensional (1D) amorphous nanomaterials combine the advantages of high active site concentration of amorphous structure, high specific surface area and efficient charge transfer of 1D materials, so they present promising opportunities for catalysis. However, how to achievie the balance between the high orientation of 1D morphology and the isotropy of amorphous structure is a significant challenge, which severely obstructs the controllable preparation of 1D amorphous materials. Guided by the hard-soft acids-bases theory, here we develop a general strategy for preparing 1D amorphous nanomaterials through the precise modulation of bond strength between metal ions and organic ligands for a moderated fastness. The soft base dodecanethiol (DT) is multifunctionally served as both structure-regulating agent and morphology-directing agent. Compared with the borderline acids (e.g. Fe2+, Co2+, Ni2+) to construct amorphous structure, soft acid of Cu+ which produced crystalline nanobelts can still be amorphized by reducing the hardness of Cu ions through redox reaction to weak Cu-SR bond. Due to the combined advantages of amorphous structure and one-dimensional morphology, amorphous CuDT nanobelts exhibited excellent electrocatalytic activity in electrochemical nitrate reduction, outperformed most of the reported Cu-based catalysts. This work will effectively bridge the gap between traditional 1D crystalline nanomaterials synthesis and their amorphization preparation.

Oxidative Stress Markers and Na,K-ATPase Enzyme Kinetics Are Altered in the Cerebellum of Zucker Diabetic Fatty fa/fa Rats: A Comparison with Lean fa/+ and Wistar Rats.

Type 2 diabetes mellitus has been referred to as being closely related to oxidative stress, which may affect brain functions and brain glucose metabolism due to its high metabolic activity and lipid-rich content. Na,K-ATPase is an essential enzyme maintaining intracellular homeostasis, with properties that can sensitively mirror various pathophysiological conditions such as diabetes. The goal of this study was to determine oxidative stress markers as well as Na,K-ATPase activities in the cerebellum of Zucker diabetic fatty (ZDF) rats depending on diabetes severity. The following groups of male rats were used: Wistar, ZDF Lean (fa/+), and ZDF (fa/fa) rats, arbitrarily divided according to glycemia into ZDF obese (ZO, less severe diabetes) and ZDF diabetic (ZOD, advanced diabetes) groups. In addition to basic biometry and biochemistry, oxidative stress markers were assessed in plasma and cerebellar tissues. The Na, K-ATPase enzyme activity was measured at varying ATP substrate concentrations. The results indicate significant differences in basic biometric and biochemical parameters within all the studied groups. Furthermore, oxidative damage was greater in the cerebellum of both ZDF (fa/fa) groups compared with the controls. Interestingly, Na,K-ATPase enzyme activity was highest to lowest in the following order: ZOD > ZO > Wistar > ZDF lean rats. In conclusion, an increase in systemic oxidative stress resulting from diabetic conditions has a significant impact on the cerebellar tissue independently of diabetes severity. The increased cerebellar Na,K-ATPase activity may reflect compensatory mechanisms in aged ZDF (fa/fa) animals, rather than indicating cerebellar neurodegeneration: a phenomenon that warrants further investigation.

Investigation of an Industrially Scalable Production of Sulfur‐Polyacrylonitrile Based Cathodes

AbstractSulfur‐polyacrylonitrile (SPAN) is a sulfur‐based active material for next‐generation lithium‐sulfur battery cathodes. Due to the covalent bonding between sulfur chains and the polymeric backbone, the shuttle effect degrading classical sulfur‐based cathodes can be suppressed while also achieving a high active material content in the cathode. In this paper, we investigate the processability of an industrially scalable SPAN active material with 38 wt.‐% of sulfur in a water‐based and scalable process route. The potential of the SPAN material for industrial adoption and the impact of the process route on the cell performance are discussed. We show that when processed correctly, the SPAN material delivers exceptional cycling stability and good C‐rate performance with ether‐based electrolytes. However, the performance of the SPAN cathode is influenced by the mixing characteristic. Using higher mixing intensities during the slurry preparation leads to deterioration of the electrochemical performance. This can be attributed to a decreasing carbon black percolation with increasing tip speed in combination with the kinetic limitation of sulfur cathodes during Li2S2 and Li2S oxidation.

Investigating biological mechanisms of colour changes in sustainable food systems: The role of Starmerella bacillaris in white wine colouration using a combination of genomic and biostatistics strategies

This study explores the biological mechanisms behind colour changes in white wine fermentation using different strains of Starmerella bacillaris. We combined food engineering, genomics, machine learning, and physicochemical analyses to examine interactions between S. bacillaris and Saccharomyces cerevisiae. Significant differences in total polyphenol content were observed, with S. bacillaris fermentation yielding 6 % higher polyphenol content compared to S. cerevisiae EC1118. Genomic analysis identified 12 genes in S. bacillaris with high variant counts that could impact phenotypic properties related to wine color. Notably, SNP analysis revealed numerous missense and synonymous variants, as well as stop-gained and start-lost variants between PAS13 and FRI751, suggesting changes in metabolic pathways affecting pigment production. Besides that, high upstream gene variants in SSK1 and HIP1R indicated potential regulatory changes influencing gene expression. Fermentation trials revealed FRI751 consistently showed high antioxidant activity and polyphenol content (Total Polyphenol: 299.33 ± 3.51 mg GAE/L, DPPH: 1.09 ± 0.01 mmol TE/L, FRAP: 0.95 ± 0.02 mmol TE/L). PAS13 exhibited a balanced profile, while EC1118 had lower values, indicating moderate antioxidant activity. The Weibull model effectively captured nitrogen consumption dynamics, with EC1118 serving as a reliable benchmark. The scale parameter delta for EC1118 was 23.04 ± 2.63, indicating moderate variability in event times. These findings highlight S. bacillaris as a valuable component in sustainable winemaking, offering an alternative to chemical additives for maintaining wine quality and enhancing colours profiles. This study provides insights into the biotechnological and fermented food systems applications of yeast strains in improving food sustainability and supply chain, opening new avenues in food engineering and microbiology.

Inducible RPE-specific GPX4 knockout causes oxidative stress and retinal degeneration with features of age-related macular degeneration

Age-related macular degeneration (AMD) is one of the leading causes of vision loss in the elderly. This disease involves oxidative stress burden in the retina leading to death of retinal pigment epithelial (RPE) cells and photoreceptors. The retina is susceptible to oxidative stress, in part due to high metabolic activity and high concentration of polyunsaturated fatty acids that undergo lipid peroxidation chain reactions. Antioxidant enzymes exist in the retina to combat this stress, including glutathione peroxidase 4 (GPX4). GPX4 specifically reduces oxidized lipids, protecting against lipid peroxidation-induced oxidative stress, which is noted in dry AMD. We hypothesize that Gpx4 knockout within the RPE will result in an environment of chronic oxidative stress yielding degeneration akin to AMD. C57BL/6J mice with a floxed Gpx4 gene were mated with Rpe65Cre/ER mice. Offspring containing Rpe65Cre ± alleles and either Gpx4 WT or Gpx4 fl/fl alleles were administered tamoxifen to induce Gpx4 knockout in Gpx4 fl/fl mice. At sequential timepoints, retinal phenotypes were assessed via in vivo imaging utilizing confocal scanning laser ophthalmoscopy and optical coherence tomography (OCT), and visual function was probed by electroretinography. Retinas were studied post-mortem by immunohistochemical analyses, electron microscopy, plastic sectioning, and quantitative polymerase chain reaction and Western analyses. The RPE-specific Gpx4 knockout model was validated via Western analysis indicating diminished GPX4 protein only within the RPE and not the neural retina. Following Gpx4 knockout, RPE cells became dysfunctional and died, with significant cell loss occurring 2 weeks post-knockout. Progressive thinning of the photoreceptor layer followed RPE degeneration and was accompanied by loss of visual function. OCT and light microscopy showed hyperreflective foci and enlarged, pigmented cells in and above the RPE layer. Electron microscopy revealed decreased mitochondrial cristae and loss of basal and apical RPE ultrastructure. Finally, there was increased carboxyethylpyrrole staining, indicating oxidation of docosahexaenoic acid, and increased levels of mRNAs encoding oxidative stress-associated genes in the RPE and photoreceptors. Overall, we show that RPE-localized GPX4 is necessary for the health of the RPE and outer retina, and that knockout recapitulates phenotypes of dry AMD.

Behcet's disease presenting as malignant hypertension induced by renovascular hypertension.

Hypertension is an uncommon manifestation of Behcet's disease, which is also an uncommon cause of renovascular hypertension. We herein report a case of malignant hypertension associated with unilateral renal artery stenosis due to vascular Behcet's disease. A 19-year-old man, who had no significant medical history, was referred to ophthalmology at our hospital because he was suspected to have uveitis and Vogt-Koyanagi-Harada syndrome. In addition to poor eyesight, he had been aware of a fever, loss of appetite, and weight loss for a month. He was admitted with markedly elevated blood pressure (222/140mmHg), hypertensive retinopathy, and acute kidney injury, who was diagnosed with malignant hypertension. Laboratory findings showed high plasma renin activity and plasma aldosterone concentration, hypokalemia, and elevated inflammatory response. Computed tomography showed an atrophic right kidney and a compensatorily enlarged left kidney. Renal computed tomography angiography revealed severe and diffuse stenosis of the right renal artery, and stenosis of the ostium of celiac artery. Since he was suspected to have uveitis and his inflammatory responses were elevated on admission, we listed Behcet's disease as a differential diagnosis. Medical interview and examination focusing on Behcet's disease revealed that the patient had recurrent oral aphthous lesions and folliculitis, and a positive pathergy test, which led to the patient being diagnosed with vascular Behcet's disease. After admission, his blood pressure was well controlled with multiple antihypertensive drugs including an angiotensin receptor/neprilysin inhibitor, and his oral aphthous lesions and skin lesion were improved with colchicine. When young men who are at a higher risk for vascular Behcet's disease show renovascular hypertension with an elevated inflammatory reaction, vascular Behcet's disease should be considered as a differential diagnosis.

Investigation of the distribution of transuranic radionuclides in marine sediment at the Montebello Islands, Western Australia

Three nuclear weapons tests were conducted in the 1950s at the Montebello Islands, Western Australia. The detonations were of different yields and configurations (two tower tests, one ship test), and led to substantial radionuclide contamination within the surrounding terrestrial and marine ecosystems. The region possesses great ecological and recreational significance, particularly within the marine environment. However, studies conducted so far have largely neglected the marine ecosystem which makes up the majority of the Montebello Island Marine Park and in which most test fallout would have deposited. Here we investigated the distribution of the transuranic radionuclides 238Pu, 239,240Pu and 241Am in marine sediment from the Montebello Islands. Marine sediment samples near Operation Mosaic G2 and Operation Hurricane were collected and analysed by gamma and alpha spectrometry. Activity concentrations of 239,240Pu across both series ranged from 45 to 2900 Bq kg−1, while 241Am levels ranged from 2.8 to 70 Bq kg−1. Higher activity concentrations were observed in sediment near the land-based, higher yield Mosaic G2 test, compared with the ship-based, lower yield Hurricane test. Sediment samples located closer to the detonation site were also observed to have higher activity concentrations. Radioactive particles of 0.94 mm and 1.5 mm in diameter were identified by analysis of size-fractioned sediment via investigation of 152Eu levels, photostimulated autoradiography and point gamma spectroscopy. Particles were confirmed to have transuranic radionuclide interiors, with surface coatings which were dominated by vitrified CaCO3. Their long-term resistance to weathering and subsequent persistence in the marine environment can therefore be attributed to their coated structural form. Our study confirms the persistence of transuranic radionuclides in Montebello Island marine sediment and highlights the need for additional studies to improve our understanding of the nuclear legacy in this region.

Evaluation of Pre-Harvest Nutrient Composition and Functional Active Substances in Various Lotus Roots.

This study investigated the impact of variety and harvest time on the visual appearance, nutritional quality, and functional active substances of six lotus root cultivars: "Xinsanwu", "Wuzhi No. 2", "Baiyuzhan", "Huaqilian", "Elian No. 6", and "Elian No. 5". Samples were collected monthly from December 2023 to April 2024. A nutrient analysis revealed a decrease in the water content with a delayed harvest. The total soluble solids and soluble sugar content peaked towards the end and middle-to-late harvest periods, respectively. Starch levels initially increased before declining, while the soluble protein exhibited a triphasic trend with an initial rise, a dip, and a final increase. The vitamin C (Vc) content varied across cultivars. Functional active substances displayed dynamic changes. The total phenolics initially decreased, then increased, before ultimately declining again. The total flavonoid content varied by both cultivar and harvest time. The phenolic acid and flavonoid content mirrored the trends observed for total phenolics and total flavonoids. Gastrodin was the most abundant non-flavonoid compound across all varieties. "Wuzhi No. 2" and "Baiyuzhan" displayed higher levels of functional active substances and starch, while the Elian series and "Xinsanwu" cultivar exhibited a greater content of Vc, soluble sugar, and soluble protein. Specific harvest periods yielded optimal results: "Wuzhi No. 2" (H1 and H5), "Huaqilian" (H2), and "Baiyuzhan" (H3 and H4) demonstrated a high nutrient and functional active substance content. Overall, the lotus roots harvested in period H4 achieved the highest score. Overall, this study provides the foothold for the rapid identification of superior lotus root cultivars and the valorization of lotus root by-products via advanced processing methods. Additionally, it offers valuable insights for market participants and consumers to select optimal varieties and harvest times based on their specific needs.