Metal Profiles Research Articles

Signs of `Everything Everywhere All at Once' formation in low-surface-brightness globular-cluster-rich dwarf galaxies

Only two ultra-diffuse galaxies (UDGs) have spatially resolved stellar population properties, showing flat to rising metallicity profiles, indicative of a different formation pathway than most dwarf galaxies. The scarcity of other low-surface-brightness (LSB) dwarfs with a similar analysis prevents a deeper understanding of this behaviour. We investigated the radial profiles of the ages, metallicities, and star formation histories of four globular cluster (GC)-rich LSB dwarfs, newly observed as part of the `Analysis of Galaxies At The Extremes' (AGATE) collaboration. DFX1 and DF07 are bona fide UDGs, while PUDG-R27 and VCC 1448 are `nearly UDGs'. Comparing their and DF44's properties to simulations, we aim to reveal their formation pathways. We used the full-spectral-fitting code to fit different spectra extracted in annular apertures in a bid to recover the stellar population properties and compute their gradients. We compared these results with a sample of literature classical dwarfs and simulations, in particular simulated UDGs. Our five LSB dwarfs have flat age and flat to rising metallicity profiles. Such age gradients are compatible with those of classical dwarfs (observed and from cosmological simulations), but the metallicity gradient diverges. All of our LSB dwarfs (except for PUDG-R27, which shows a pronounced increasing metallicity) are compatible with being on the extreme tail of the age--metallicity gradient relation, suggesting a coeval formation, forming the galaxy all at once. This sample of GC-rich LSB dwarfs with spatially resolved properties provides further evidence that they follow a different formation path than classical dwarfs. However, larger samples with higher-S/N spectra and varying amounts of GC richness are required to set robust constraints on the formation pathways of LSB dwarf galaxies.

Metalloproteomic analysis of hemophilic arthropathy synovial tissue: insights into metal overload and pathogenesis.

Hemophilic arthropathy (HA) is a joint disease characterized by local iron overload stemming from erythrocyte rupture and closely linked to synovial lesions. However, the precise molecular characteristics of clinical HA synovial samples remain to be defined. To gain insight into HA synovial tissue lesions, we utilized a metalloprotein strategy to compare the metal and protein spectra of HA with those of osteoarthritis and rheumatoid arthritis. We collected synovial samples from patients with HA, osteoarthritis, and rheumatoid arthritis. Tissue metal and protein profiles were obtained by metallomics and proteomics, respectively. Finally, metalloproteomics strategies compared metal content, proteins, metalloproteins, and the life processes involved. Our metallomics analysis revealed an explicit increase in heavy metal content, particularly arsenic and mercury, in HA synovial samples. Through proteomics, we delineated specific metalloproteins and identified correlations between metals and pathways. These findings yield valuable insights into the pathogenesis of HA and offer potential therapeutic targets for conditions characterized by iron overload.

Effects of different processing methods on the functional, nutritional, and physicochemical profiles of cowpea leaf powder.

Indigenous fruits and vegetables can improve food security and biodiversity. However, their use is hindered by perishability, seasonal availability, cooking losses, lack of nutritional composition data, and connections to low socioeconomic status. This study aimed to process cowpea leaves into powder and determine the effect of five home-cooking methods on their protein, functional, physicochemical, and heavy metal profiles. Cowpea leaves were boiled, blanched, steamed, sous-vide cooked, and stir-fried, at 5, 10, and 15min before dehydration at 60°C. Cowpea leaves contain protein up to 20g/100g. The leaves are rich in calcium, potassium, and zinc, providing up to 70% of the adult recommended dietary allowance for calcium and potassium per 100g of powder. Cowpea leaf powder exhibited good water/oil absorption and rehydration capacities. Sous-vide and steamed cowpea leaves provided an overall superior nutritional profile (p≤0.05). Heavy metals in the cowpea leaf powders were below the WHO permissible limits except for aluminum and high arsenic levels. This study demonstrated that cowpea leaf powders could be potentially incorporated into foods to improve functional properties and nutrient intake.

EXPERIMENTAL ASSESSMENT OF CHANGES IN THE STRUCTURE OF FOOD-GRADE ANTI-CORROSION STEEL DUE TO THE USE OF FLOWDRILL TECHNOLOGY

Machining technologies are constantly evolving in line with new material development strategies, with further advances in cutting tools accelerating these changes even further. Growing demands for increased productivity and production efficiency have led us to today's advanced level of technology. Recently, steel structures made of thin sheets and strips, which are processed by bending, three-dimensional forming or pressing, often in combination with technologies such as ribbing, have been increasingly used. Open and closed rolled profiles are increasingly being replaced by more economical and lighter sheet metal strip materials, which provide similar or even higher strength at a significantly lower weight. Flowdrill technology is often used when joining light sheet metal profiles in a demountable manner, which enables the creation of a cylindrical surface necessary for the subsequent shaping of the thread. Flowdrill thermal drilling technology represents an innovative and forward-looking method of producing precise cylindrical housings in thin-walled materials such as sheets, profiles of various shapes and pipes. This technology uses frictional heat, which is generated by a combination of high tool speeds and axial force acting on the workpiece. Frictional heat causes the material to soften, allowing the tool to smoothly penetrate the workpiece and form a sleeve from the displaced material [Rimar 2023]. This process inspired experimental measurements aimed at analyzing the influence of technology parameters on the material. The aim of the experiments was to investigate structural changes in food-grade anti-corrosion steel EN ISO X10CrNi18-8 (17241) as a result of Flowdrill thermal drilling, by analyzing the state of the material before and after the application of this technology. The results of these measurements will bring valuable knowledge to technologists, which will help them choose suitable materials and drilling technologies in practice.

Metal Content of the Yellowtail Fish (Caesio cuning) Consumed by the Community in Boedingi, North Konawe, Indonesia: An Environmental Health Risk Assessment in the Mining Area

The rapid development of mining activities, the shipping industry, and public transportation across the land and water areas of Boedingi Village can have both positive and negative impacts on the water quality of this area. This study aimed to determine the heavy metal content in yellowtail fish (Caesio cuning), a type of fish that is generally consumed by Boedingi villagers in North Konawe, Indonesia. A descriptive method with an environmental health risk assessment (EHRA) was employed to measure metal profiles (Pb, Cd, and Hg). The results showed that the metal levels in the water exceeded the thresholds, indicating significant heavy metal pollution. In addition, the Cd levels of the fish surpassed the food safety standard according to the USA Food and Drug Administration (FDA). Since Indonesia began its large-scale shift from conventional to electrical transportation, global and government collaboration have become critical in managing the environmental and health impacts of the related industries. This is especially important because this area is one of the largest nickel producers (the raw material of electrical transportation) both nationally and globally.

Large Dark Matter Content and Steep Metallicity Profile Predicted for Ultradiffuse Galaxies Formed in High-spin Halos

We study the stellar properties of a sample of simulated ultradiffuse galaxies (UDGs) with stellar mass M ⋆ = 107.5–109 M ⊙, selected from the TNG50 simulation, where UDGs form mainly in high-spin dwarf-mass halos. We divide our sample into star-forming and quenched UDGs, finding good agreement with the stellar assembly history measured in observations. Star-forming UDGs and quenched UDGs with M ⋆ ≥ 108 M ⊙ in our sample are particularly inefficient at forming stars, having 2–10 times less stellar mass than non-UDGs for the same virial mass halo. These results are consistent with recent mass inferences in UDG samples and suggest that the most inefficient UDGs arise from a late assembly of the dark matter mass followed by a stellar growth that is comparatively slower (for star-forming UDGs) or that was interrupted due to environmental removal of the gas (for quenched UDGs). Regardless of efficiency, UDGs are 60% poorer in [Fe/H] than the population of non-UDGs at a fixed stellar mass, with the most extreme objects having metal content consistent with the simulated mass–metallicity relation at z ∼ 2. Quenched UDGs stop their star formation in shorter timescales than non-UDGs of similar mass and are, as a consequence, alpha enhanced with respect to non-UDGs. We identify metallicity profiles in UDGs as a potential avenue to distinguish between different formation paths for these galaxies, where gentle formation as a result of high-spin halos would present well-defined declining metallicity radial profiles while powerful-outflows or tidal stripping formation models would lead to flatter or constant metallicity as a function of radius due to the inherent mixing of stellar orbits.

Using mercury and lead stable isotopes to assess mercury, lead, and trace metal source contributions to Great Salt Lake, Utah, USA

Great Salt Lake is a critical habitat for migratory birds that is threatened by elevated metal concentrations, including mercury (Hg) and lead (Pb), and is subject to severe hydrologic changes, such as declining lake level. When assessing metal profiles recorded in Great Salt Lake sediment, a large data gap exists regarding the sources of metals within the system, which is complicated by various source inputs to the lake and complex biogeochemistry. Here, we leverage Hg and Pb stable isotopes to track relative changes in metal source contributions to Great Salt Lake over time. Mercury and Pb concentrations increase in sediments deposited after 1920 and peak between 1965 and 1995, following closure of several local smelters and the onset of increased emission controls. The nominal associations above are confirmed via Hg stable isotopes in pre-1920 background sediments, which reflect atmospheric inputs from regional and global origin, whereas Hg and Pb stable isotopes together indicate that elevated metal concentrations in mid-late 20th century sediments reflect increased mining/smelting inputs. The observed minimal rebound towards pre-1920 Pb isotope signatures in 21st century sediments indicates that mining/smelting inputs, though reduced, remain a primary source of Pb to Great Salt Lake. In contrast, the more pronounced rebound of Hg stable isotope signatures to pre-1920 values indicate a greater contribution of atmospheric inputs of regional/global origin to current Hg inputs, though Hg concentrations are ~10 times greater than pre-1920 background values due to global increases in atmospheric Hg concentrations or possibly slow recovery from local contamination. The importance of regional/global Hg sources to the system suggests that reductions in Hg bioaccumulation in the open water food webs of Great Salt Lake are more dependent on national and global reductions in Hg emissions and management strategies to limit methylmercury production within system. This work highlights the utility of using coupled Hg and Pb stable isotope values to assess trace metal pollution sources and pathways in aquatic systems.

Radial Profiles of Σ*, ΣSFR, Gas Metallicity, and Their Correlations across the Galactic Mass–Size Plane

We analyzed the global and resolved properties of approximately 1240 nearby star-forming galaxies from the MaNGA survey, comparing compact and extended galaxies—those with smaller and larger radii (R e), respectively—at a fixed stellar mass (M *). Compact galaxies typically exhibit lower H i gas fractions, higher dust extinction, higher metallicity, greater mass concentration, and lower angular momentum on a global scale. Radial profiles of stellar mass surface density (Σ*) and star formation rate surface density (ΣSFR) as functions of the effective radius (R/R e) reveal that compact galaxies display steeper gradients and higher values, resulting in elevated specific star formation rates (sSFRs) in their inner regions compared to their outskirts. At a given Σ*, compact galaxies have higher sSFRs than extended galaxies, particularly in low-mass galaxies (log(M */M ⊙) ≤ 1010). Additionally, their metallicity profiles differ significantly: extended galaxies have steeper metallicity gradients, while compact galaxies exhibit flatter slopes and higher metallicity at a given R/R e. After accounting for the dependence of metallicity on M * and Σ*, no further correlation with SFR is observed. The combination of higher sSFR and potentially higher star formation efficiency in compact galaxies suggests that their central gas is being rapidly consumed, leading to older stellar populations, as indicated by D n (4000) and EW(Hδ A ), and resulting in faster central growth. Our results reveal that radial SFR profiles cannot be fully determined by M * and Σ* alone; other factors, such as galaxy size or angular momentum, must be considered to fully understand the observed trends.

Particle induced x-ray emission (pixe) assisted technique in the evaluation of potential ecological risks of heavy metals in surface sediments of Oba-Ile River, Ifelodun Local Government Area, Osun-State, Nigeria

The seasonal evaluation of trace elements in the surface sediments collected from Oba-Ile River, using Particle Induced X-Ray Emission (PIXE) Spectroscopy had been carried out. This was done so as to provide information about the pollution status of the river during the rainy and dry seasons. The samples were subjected to trace metal profiling using a 2.5 Mev proton available at the Ion Beam Analysis (IBA)/accelerator laboratory, Centre for Energy Research and Development (CERD), Obafemi Awolowo University, Ile-Ife. The facility is centered on a NEC 5SDH 1.7 MV Pelletron accelerator, equipped to provide proton and helium ions. A multi-elemental estuarine sediments referenced material (SRM 1646a purchased from NIST) was used for the determination of H-value which was subsequently used for analyzing the samples and assured the accuracy of the experimental procedure. The order of abundance of the 16 elements identified was Si > Fe >Al >K > Ca >Ti > Na > Mg > Zr > Mn > Sr > V > Cr > Zn > Pb > Cu. The contamination factor indicated that the metals presented a low contamination factor (LCf) to moderate contamination factor (MCf) except for Fe and Zr which presented a considerable contamination (CCf) and a very high contamination factor (VHCf) respectively. Other contamination indices indicated that Fe had either a moderate enrichment (ME) factor or a significant enrichment (SE) factor, thereby suggesting that Oba-Ile River sediment was particularly enriched in Fe

Black Sands of Iwo Jima: How the Past Can Improve the Future of Warfare

Heavy metal soil contamination persists on Iwo Jima’s Invasion Beach, a site of historical significance from WWII, renowned for its critical role in the Pacific theater and its distinctive black volcanic sand. Despite the sand being collected as war memorabilia, limited research has specifically addressed the heavy metal composition of this sand and the associated contamination risks. This study aims to quantify heavy metal concentrations in soil samples from Invasion Beach, compare them with those from non-affected areas, identify sources of contamination, and assess the environmental and health impacts of these metals. Using X-ray fluorescence (XRF), soil samples were analyzed from various locations on Invasion Beach and compared to non-affected control sites. Statistical analyses, including t-tests, one-way ANOVA, Mann-Whitney U tests, and Multivariate Analysis of Variance (MANOVA), to compare the heavy metal concentrations between Iwo Jima and background samples. The t-tests and ANOVA revealed significant differences in the concentrations of metals such as chromium (Cr) and mercury (Hg), with p-values indicating strong statistical significance (p < 0.05). Mann-Whitney U tests further confirmed significant distributional differences for Cr, Hg, and Zn, while the MANOVA results highlighted a significant overall difference in metal profiles when considering all metals collectively (Wilks’ Lambda = 0.020, p = 0.049). These elevated levels are directly attributed to the intensive military activities and munitions used during the war, as evidenced by the specific metal signatures consistent with military debris. This underscores the potential environmental and public health risks, including disruptions to nutrient cycles, reduced soil fertility, impaired plant growth, and contamination of groundwater and surface water. This research emphasizes the urgent need for adopting environmentally friendly military technologies to minimize the ecological impact of warfare. It also highlights the importance of further studies, the development of sustainable alternatives, increased public awareness, and the implementation of environmental regulations, alongside long-term health monitoring of populations living near contaminated sites. There is limited literature on general soil contamination and the environmental effects of military operations, with no specific studies on Iwo Jima’s Invasion Beach. This study aims to fill this gap by providing empirical data on heavy metal concentrations and analyzing their sources.

(Invited) Application of Electroless Plating to 3D Interconnection Technology of LSIs

In the interconnection of LSIs and 3D integration technologies, high aspect ratio structures (HRS) such as via holes and trenches with very small dimensions were used. In these HRSs, deposition of metals has been studied using CVD or ALD which are based on a surface reaction dominated deposition process. On the other hand, electroless plating is also based on the surface reaction mechanism, therefore a conformal deposition profile is possible. Furthermore, with use of additives, control of deposition profile such as bottom-up fill is enabled by the electroless plating. Production cost would be significantly reduced by the use of electroless plating as compared to CVDs which use high vacuum chambers. Cu electroless bottom-up fill (superfill) is possible for sub-micrometer diameter holes with addition of inhibitors. Conformal deposition profile of electroless Co-alloy barrier metals is achieved for a high aspect ratio TSVs. In the high aspect TSV structures, a combination of electroless barrier metal and Cu electroplated bottom-up fill would be the most important technology. Furthermore, I would like to introduce electroplating of Ru using hydrazine as a reducing agent. This technology enables to deposit a Ru film which shows significant reduction of resistivity after annealing in the forming gas ambient.

Current Transient-Based Electrochemical Method for Detecting Li Plating during Fast-Charging of Li-Ion Batteries

Li metal plating in Li-ion batteries (LIBs) has been recognized as a major obstacle for realizing fast-charging of LIBs, as Li metal deposits on graphite anodes often cause drastic capacity loss and may trigger internal short-circuiting, raising safety concerns. Therefore, extensive research efforts have been devoted to developing methods for detecting plated Li. However, proposed methods often required specialized equipment or sophisticated experimental methods, which cannot be implemented in practical cell operation conditions. Recently, diagnostic methods based on characteristic electrochemical signals of plating have been attracted significant research interest as they enable non-destructive, in operando detection that can be directly applied to the state-of-the-art battery management systems.Herein, we present an electrochemical method for detecting Li plating based on the cell current transient during constant-voltage (CV) charging. To study the electrochemical behavior of full cells under fast-charging conditions, a three-dimensional (3D) full-cell model is constructed with a stochastically generated anode. To generate the geometry of graphite anodes with realistic particle shapes, we employ 3D Voronoi tessellation and Catmull-Clark subdivision methods. In the model, we assume that the plating/stripping reaction of Li-metal is partially reversible, to reflect the highly irreversible nature of Li metal deposits.To extract the characteristic signal of Li plating from the electrochemical behavior of full cells, we simulate the charging process of full cells with three different reaction modes for the graphite anode: (i) intercalation reaction, (ii) intercalation and irreversible Li plating reaction, and (iii) intercalation and partially reversible Li plating/stripping reactions. The results of electrochemical modeling show that, without the Li stripping reaction, the cell current monotonously decreases as CV charging proceeds. Conversely, the cell with partially reversible Li plating/stripping reactions exhibits a characteristic peak in the cell current profile. The amount of plated Li metal and reaction current profiles suggest that the peak appears with the depletion of plated Li. Upon the depletion of plated Li, the Li stripping reaction current, which contributes to the cell current in an opposite direction to the intercalation reaction current, rapidly decreases, causing a transient increase in the cell current during CV charging. As a result, a peak or plateau appears in the current profile of the cell that experiences Li plating and stripping during charging. The effect of the reaction rates of intercalation, Li plating, and Li stripping reactions on the characteristic signal is further explored by electrochemical modeling. Specifically, the amount of plated Li and the reaction rate for Li stripping critically affect the detectability of the peak/plateau in the cell profile. Based on the simulation results, we demonstrate that the peak/plateau in cell current profiles during CV charging can be utilized as a characteristic electrochemical signal of Li plating. Moreover, experimental studies with [LiNi0.8Co0.1Mn0.1O2|graphite] full cells are conducted to demonstrate the practical applicability of the proposed electrochemical method for detecting Li plating during fast-charging cycling.

Gene biomarkers in estuarine oysters indicate pollution profiles of metals, brominated flame retardants, and poly- and perfluoroalkyl substances in and near the Laizhou Bay

The Laizhou Bay (LZB) is of ecological and fishery importance. The discharge of effluents containing numerous pollutants into the LZB via rivers poses significant risks to ecosystem and human health. Estuarine biomonitoring is therefore crucial for assessing the contribution of rivers to coastal pollution and their impacts on species. Estuarine oyster Crassostrea gigas is a preferable bioindicator to pollution conditions. This study measured accumulation of contaminants and expression levels of gene biomarkers in the LZB and Northern Shandong Peninsula (NSP) oysters. The LZB oysters accumulated higher levels of brominated flame retardants (BFRs) and poly- and perfluoroalkyl substances (PFAS), while NSP oysters exhibited greater accumulation of heavy metals. Decabromodiphenyl ethane was the dominant BFR, while perfluorooctanoic acid and perfluoro-2-methoxyacetic acid were the dominant PFASs in oysters. The expression of gene biomarkers effectively distinguished the LZB and NSP oysters, with CYP2 subfamilies expression correlating with BFRs and PFASs and metallothionein expression indicating heavy metals. The reproductive endocrine and neuroendocrine-immune systems in oysters might be the targets of BFRs and heavy metal pollution, respectively. The negative correlation between contaminant accumulation and gene expression might be explained by adaptive evolution, emphasizing the need to consider genetic diversity in ecological risk assessments.

Alterations in zinc, copper, and iron levels in the retina and brain of Alzheimer's disease patients and the APP/PS1 mouse model.

Transition metals like copper (Cu), iron (Fe), and zinc (Zn) are vital for normal central nervous system function and are also linked to neurodegeneration, particularly in the onset and progression of Alzheimer's disease (AD). Their alterations in AD, identified prior to amyloid plaque aggregation, offer a unique target for staging pre-amyloid AD. However, analysing their levels in the brain is extremely challenging, necessitating the development of alternative approaches. Here, we utilized laser ablation-inductively coupled plasma-mass spectrometry and solution nebulization-inductively coupled plasma-mass spectrometry to quantitatively measure Cu, Fe, and Zn concentrations in the retina and hippocampus samples obtained from human donors (i.e. AD and healthy controls), and in the amyloid precursor protein/presenilin 1 (APP/PS1) mouse model of AD and wild-type (WT) controls, aged 9 and 18 months. Our findings revealed significantly elevated Cu, Fe, and Zn levels in the retina (*P<.05, P<.01, and P<.001) and hippocampus (*P<.05, *P<.05, and *P<.05) of human AD samples compared to healthy controls. Conversely, APP/PS1 mouse models exhibited notably lower metal levels in the same regions compared to WT mice-Cu, Fe, and Zn levels in the retina (**P<.01, *P<.05, and *P<.05) and hippocampus (**P<.01, **P<.01, and *P<.05). The contrasting metal profiles in human and mouse samples, yet similar patterns within each species' retina and brain, suggest the retina mirrors cerebral metal dyshomoeostasis in AD. Our findings lay the groundwork for staging pre-AD pathophysiology through assessment of transition metal levels in the retina.

Decoupling Sources of Anthropogenic Influences on Sediments of the Visovac Lake (Krka National Park, Croatia) Using Multiparametric Approach.

Historical changes of sediment characteristics and levels of inorganic and organic contaminants were studied in dated sediment cores from the Visovac Lake, situated in the Krka National Park, Croatia, to identify the main sources of anthropogenic pressures on this highly protected system. Depth distributions of lithogenic elements showed a steady decrease of terrigenous inputs due to the reduction in agricultural activities in the area, which was particularly pronounced during the 1991-1995 war in Croatia. Vertical and longitudinal distributions of Cd and Zn indicated that they are predominately of anthropogenic origin. The historical profiles of these toxic metals coincide well with the recorded production of metal industry in the upper reach of the Krka River with a sharp decrease reflecting the interruption by the war and slow recovery afterwards. By contrast, the recovery of the tourist industry in Krka NP after the war was accompanied by increasing contamination by elements characteristic of boat and car traffic (Sn, Cu, Pb) as well as oil pollution. The contamination with polycyclic aromatic hydrocarbons and polychlorinated biphenyls was only moderate. Although levels of metallic and organic contamination can be considered relatively low, the observed shift from industrial to tourism-related sources indicated that touristic activities should also be regarded as a possible threat for this vulnerable karst aquatic ecosystem.

Spatially–resolved gas-phase metallicity in Seyfert galaxies

Abstract We explore the relations between the gas-phase metallicity radial profiles (few hundred inner parsec) and multiple galaxy properties for 15 Seyfert galaxies from the AGNIFS (Active Galactic Nuclei Integral Field Spectroscopy) sample using optical Integral Field Unit (IFU) observations from Gemini Multi-Object Spectrographs (GMOS) and Multi Unit Spectroscopic Explorer (MUSE) processed archival data. The data were selected at z ≲ 0.013 within black hole mass range [6 &amp;lt; log (MBH/M⊙) &amp;lt; 9] with moderate 14–150 keV X-ray luminosities $\left[42\, \lesssim \, \log L_X (\rm erg\, s^{-1})\, \lesssim \, 44\right]$. We estimated the gas-phase metallicity using the strong-line methods and found mean values for the oxygen dependent (Z ∼ 0.75 Z⊙) and nitrogen dependent (Z ∼ 1.14 Z⊙) calibrations. These estimates show excellent agreement with ΔZ ≈ 0.19 dex and ΔZ ≈ 0.18 dex between the mean values from the two strong-line calibrations for GMOS and MUSE respectively, consistent with the order of metallicity uncertainty via the strong-line methods. We contend that our findings align with a scenario wherein local Seyferts have undergone seamless gas accretion histories, resulting in positive metallicity profile over an extended period of time, thereby providing insights into galaxy evolution and the chemical enrichment or depletion of the universe. Additionally, we argue that metal-poor gas inflow from the local interstellar medium (ISM) and accreted through the circumgalactic medium (CGM) onto the galaxy systems regulates the star formation processes by diluting their central metallicity and inverting their metallicity gradients, producing a more prominent anti-correlation between gas-phase metallicity and Eddington ratio.

Dwarf galaxies as a probe of a primordially magnetized Universe

Aims. The true nature of primordial magnetic fields (PMFs) and their role in the formation of galaxies remains elusive. To shed light on these unknowns, we investigated their impact by varying two sets of properties: (i) accounting for the effect of PMFs on the initial matter power spectrum and (ii) accounting for their magneto-hydrodynamical effects on the formation of galaxies. By comparing both, we can determine the dominant agent in shaping galaxy evolution. Methods. We used the magneto-hydrodynamics code RAMSES to generate multiple new zoom-in simulations for eight different host halos of dwarf galaxies across a wide luminosity range of 103 − 106 L⊙. These halos were selected from a ΛCDM cosmological box, tracking their evolution down to redshift z = 0. We explored a variety of primordial magnetic field (comoving) strengths of Bλ ranging from 0.05 to 0.50 nG. Results. We find that magnetic fields in the interstellar medium not only modify star formation processes in dwarf spheroidal galaxies, but these fields also entirely prevent the formation of stars in less compact, ultra-faint galaxies with halo masses and stellar masses below, respectively, ∼2.5 × 109 and 3 × 106 M⊙. At high redshifts, the impact of PMFs on host halos of dwarf galaxies through the modification of the matter power spectrum is more dominant than the influence of magneto-hydrodynamics in shaping their gaseous structure. Through the amplification of small perturbations ranging in mass from 107 to 109 M⊙ in the ΛCDM+PMFs matter power spectrum, primordial fields expedite the formation of the first dark matter halos, leading to an earlier onset and a higher star formation rate at redshifts of z &gt; 9. We investigated the evolution of various energy components and demonstrated that magnetic fields with an initial strength of Bλ ≥ 0.05 nG exhibit a strong growth of magnetic energy, accompanied by a saturation phase that begins soon after the growth phase. These trends persist consistently, regardless of the initial conditions or whether it is the classical ΛCDM model or ΛCDM modified by PMFs. Lastly, we investigated the impact of PMFs on the present-time observable properties of dwarf galaxies, namely: the half light radius, V-band luminosity, mean metallicity, and velocity dispersion profile. We find that PMFs with moderate strengths of Bλ ≤ 0.10 nG show an impressive agreement with the scaling relations of the observed Local Group dwarfs. However, stronger fields lead to larger sizes and higher velocity dispersions.

Optimization of the Design of a Greenhouse LED Luminaire with Immersion Cooling

Modern agriculture, with the use of artificial lighting, requires high-intensity LED luminaires with compact dimensions. In this regard, new approaches to the design of LED luminaires using both new materials and technical solutions have been considered. The theoretical evaluation of the influence of different materials on the efficiency of removal of thermal energy from LEDs was shown. A new material PMS-5 is proposed and evaluated as an immersion liquid, which can be used as an effective heat sink in the lower part of the luminaire up to the level of LEDs located in the top light LED luminaires. The proposed polymethylsiloxane PMS-5 liquid has more than twice the thermal conductivity (0.167 W/(m·K)) of HFE7200 and NS15 liquids used in immersion-cooled LED luminaires. Based on the theoretical evaluation, the requirements for parameters, such as metal profile area, immersion liquid volume, wall thickness area, and external area of the cylinder, are highlighted and shown. The noted parameters have a key role in the design of an efficient top light LED luminaire. It has been shown that the design of the metal profile significantly affects the efficiency of the removal of thermal energy from LEDs and it is necessary to use specialized profiles optimized for the diameter of the LED luminaire cylinder. A number of LED luminaire designs were proposed, depending on the thermal properties of the construction materials, technical and economic performance, as well as actual operating and installation conditions. The analysis of the presented theoretical evaluations allowed overlay of the design basis of LED luminaires within the presented concept and top light.

A study investigating heavy metals in salmonids products marketed in Spain

Spain is the second European country that consumes the most fish, with salmon being the second most consumed. Therefore, the safety of salmonids for human health is a hot topic that requires more research. In this study we measured arsenic, cadmium, mercury and lead (As, Cd, Hg and Pb respectively) in 54 samples of four salmonid species (Oncorhynchus gorbuscha, O. keta, O. mykiss and S. salar) acquired in Asturias (North Spain) supermarkets, imported from other regions. O. mykiss samples (N = 30) from local farms located on two nearby rivers in the same region were also analyzed as well as river water. Marketed samples were authenticated through DNA barcoding. No species substitution was found, while five samples from O. keta exhibited contradictory information about the geographical origin in the label. The label indicated that they were from “Northwest Pacific” and “FAO area 67”. The Northwest Pacific catch zone corresponds to FAO 61, while FAO 67 is located in Northeast Pacific. Only one market sample exceeded the legal limit of Pb and none for other metals. Five S. salar samples from Denmark surpassed the safety limits marked for As, and other five samples from different species for Hg, but correcting for the expected proportion of the toxic form of these elements only three exceeded the safety limits for Hg and none for As. The importance of local contamination was emphasized for different metal profiles according to different content in water. Overall, health risk assessment indicate that salmonids sold in Spain can be considered safe for human consumption.

Understanding physiological, elemental distribution and bioaccumulation responses of crustose and foliose lichens in the vicinity of coal-based thermal power plant, Raebareli, Uttar Pradesh, India

Environmental pollution, especially from coal-based thermal power plants, poses significant risks to human respiratory health and the environment. This study evaluates the diversity of lichens in the areas. Physiological and bioaccumulation responses of two crustose lichens (Bacidia incongruens and Rindoina sophodes) and one foliose lichen (Pyxine cocoes) in the vicinity of the Feroz Gandhi Unchahar National Thermal Power Corporation, Raebareli, Uttar Pradesh, India were also assessed. These lichens, exposed to emissions including fly ash, greenhouse gases, metals, and particulate matter were analyzed for metal accumulation and physiological responses. Changes in physiological parameters and metal profiles concerning distance from the coal-based thermal power plant to the outskirts were analyzed for B. incongruens, R. sophodes and P. cocoes by utilizing Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The study identified 18 lichen species from 12 genera and 10 families in the area, with Pyxine sorediata newly recorded in Uttar Pradesh. The dominant species, B. incongruens, P. cocoes, and R. sophodes, preferred substrates like Mangifera indica, Acacia nilotica, and Azadirachta indica bark. Physiological analyses revealed variations in pigment concentrations, with significant differences in chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, and chlorophyll degradation, while protein content remained stable. Metal accumulation studies showed nine metals with distinct patterns, B. incongruens had higher concentrations in the west (52730.61 µg g-1) and P. cocoes in the east (23628.32 µg g-1). Correlation analyses indicated significant relationships between paired elements, suggesting specific sources of environmental contamination. This research highlights the significance of integrating physiological and environmental factors to understand lichen responses to coal based thermal power plant.