Search Results (935)

Selenium (Se) and silicon (Si) have been demonstrated to mitigate the adverse effects of cadmium (Cd) stress on the growth of various higher plants. However, the distinct mechanisms by which Se and Si, when applied to soil, alleviate the toxicity of Artemisia argyi under Cd stress remain unclear. This study employed A. argyi as the experimental material and simulated a Cd stress environment in soil pot experiments by adding CdCl₂·2.5H₂O at concentrations of 4 mg kg⁻¹ and 10 mg kg⁻¹. Exogenous Se in the form of Na₂SeO₃ (2 mg kg⁻¹) or Si in the form of Na₂SiO₃ (20 mg kg⁻¹) was applied simultaneously. After 90 days of combined exposure, the study investigated the differential mechanisms by which Se and Si application influenced Cd uptake by roots, its translocation within aboveground and underground tissues, and the antioxidant system of A. argyi under two levels of Cd stress. The results indicate that under Cd stress conditions, the application of Se significantly promotes the growth of A. argyi. Under both Cd concentration treatments, the application of Se or Si alone markedly reduces the Cd content in the aboveground parts of A. argyi. This reduction may be attributed to alterations in the subcellular distribution of Cd, decreased Cd content in organelles, and increased Cd sequestration in cell walls and soluble components. Furthermore, the application of Se or Si in soil can enhance the content of osmoregulatory substances, chlorophyll, and plant chelating agents in A. argyi leaves while reducing the levels of malondialdehyde (MDA) and reactive oxygen species (ROS), particularly at high Cd concentrations. The findings suggest that the alleviation of Cd toxicity by exogenous Se is primarily due to its role in inhibiting Cd uptake and translocation to shoots, as well as strengthening Cd compartmentalization in root cell walls and enhancing the antioxidant defense system. In contrast, exogenous Si primarily mitigates Cd toxicity by restricting Cd translocation from underground to aboveground plant tissues. Full article

Background: Foods containing nutraceuticals from the mineral element group are being developed to compensate for the problem of deficiency in billions of people around the world. This research focuses on essential elements of patented cereal-based mixtures to complement the deficiencies of these elements and, at the same time, assesses their safety in terms of toxic elements in the human diet. Methods: The mineral and trace element contents in the mixtures were determined using the ICP-MS method with a subsequent evaluation of the contributions of the mixtures to the essential and toxic reference values based on dietary intakes and exposures for adults at 60, 80 and 100 kg of adult body weight and a portion size of 50 g. The potential health risk was evaluated using a metal pollution index. Results: The concentrations of minerals and trace elements in the cereal-based mixtures analyzed were as follows: K (up to 4150 µg/g) ≥ P > Mg > Ca > Na > Fe > Zn > Mn > Cu > Al > Ba (up to 4.40 µg/g) > Sr (up to 480 ng/g) ≥ Ti ≥ Ni > Ce ≥ Co > As ≥ Cs > Ag ≥ Li > Se > Be > Cr > Tl > Pb ≥ Hg > Ho > Cd > Sn (up to 1.12 ng/g). The mixtures contribute significantly to the reference values for Mn, Cu, Zn, Fe, and P for adults. Individual dietary exposure values of toxic elements for adults weighing 60 kg decrease in this order: Al (10.1 µg/kg bw/day) > Ni (362 ng/kg bw/day) > As ≥ Pb > Ag > Hg > Cd > and Sn (0.93 ng/kg bw/day). Conclusions: In terms of Regulation (EU) No 1924/2006 of the European Parliament and of the Council on nutrition and health claims made on foods, the cereal-based mixtures could be labelled “source of” Mn, Cu, Zn, Fe, and P when their contributions to the reference values exceeded 15%; in addition, “low sodium/salt” or “very low sodium/salt” can be applied. The mixtures contribute insignificantly to the toxic reference values of Al, Sn, Hg, Cd, Ni, and Ag, and the exposure values of Pb for developmental neurotoxicity, nephrotoxicity, and cardiovascular effects were considered safe. Regarding the metal pollution index of mixtures, there is no concern for potential health effects. Cereal-based mixtures are suitable for use in the food industry as a potential source of beneficial micronutrients for the human diet, although bioaccessible studies should not be neglected. Full article

Purpose: This study aimed to investigate the migration and distribution characteristics of trace elements in the soil–tea system in the Cuiya tea area of Meitan County, Guizhou Province. Methods: The contents of trace elements (Cd, Fe, La, Mg, Mn, Ni, Se, Pr, Sm, Zn) in tea and soil samples were determined by inductively coupled plasma emission spectrometry (ICP-OES). Results: The average contents of heavy metals in soil and tea from Meitan County were below the Chinese national standards, while also meeting the criteria for selenium enrichment. Within the soil–tea system, Mn in tea leaves exhibited a significant negative correlation with soil Mn, while Cd showed a significant positive correlation with soil Cd. This pattern was consistent across both the topsoil and subsoil. The tea plants exhibited a high enrichment capacity for Mn, Mg, and Zn, but a low capacity for Sm, Fe, and Cd. Among the studied areas, the enrichment effect was most pronounced in SL, XH, and MJ towns. Conclusions: Significant spatial variations were observed in the concentrations of trace elements in both tea and soil across the Meitan tea area. This study provides a scientific basis for understanding the enrichment and migration of trace elements within the soil–tea system of Meitan County, Guizhou, and for tracing the geographical origin of its tea. Full article

This study investigated the optimization of optical film configurations to mitigate angular color deviation—a persistent challenge in quantum dot (QD) backlight displays. A white backlight was implemented by placing a yellow CdSe-based QD film on a blue edge-lit backlight, followed by various combinations of prism and diffusion films. Optical characteristics, including luminance, spectral distribution, and chromaticity coordinates, were systematically measured over a viewing-angle range of −70° to 70° for different film arrangements. Applying one or two prism films significantly enhanced normal luminance and improved color conversion efficiency by forming vertical optical cavities; however, this also introduced the side-lobe phenomenon, leading to color non-uniformity. Placing a diffusion film between the QD and prism films did not resolve these issues, whereas positioning it as the topmost layer above the prism films effectively eliminated color dispersion and produced a uniform luminance distribution. These results provide practical design guidelines for optimizing optical film stacks in QD-enhanced backlight units to achieve superior color uniformity in LCD displays. Full article

Emissions from civil aviation not only degrade the environmental quality around airports but also have the significant effects on climate change. According to the flight schedules, aircraft/engine combination information and revised emission factors from the International Civil Aviation Organization (ICAO) Aircraft Engine Emission Databank (EEDB) based on meteorological data, the emissions of climate forcers (CFs: BC, CH₄, CO₂, H₂O, and N₂O), conventional air pollutants (CAPs: CO, HC, NO_X, OC, PM_2.5, and SO₂), and hazardous heavy metals (HMs: As, Cu, Ni, Se, Cr, Cd, Hg, Pb, and Zn) from flights of civil aviation of eight airports in Shandong in 2018 and 2020 are estimated in this study. Moreover, the study quantifies the impact of COVID-19 on civil aviation emissions (CFs, CAPs, and HMs) in Shandong, revealing reductions of 47.45%, 48.03%, and 47.45% in 2020 compared to 2018 due to flight cuts. By 2020, total emissions reach 9075.44 kt (CFs), 35.57 kt (CAPs), and 0.51 t (HMs), with top contributors being Qingdao Liuting International Airport (ZSQD) (39.60–40.37%), Shandong Airlines (26.56–28.92%), and B738 aircraft (42.98–46.70%). As byproducts of incomplete fuel combustion, the shares of CO (52.40%) and HC (47.76%) emissions during taxi/ground idle mode are significant. In contrast, emissions during cruise phase are the dominant contributor of other species with a share of 74.67–95.61% of the associated total emissions. The findings highlight the disproportionate role of specific airlines, aircraft, and operational phases in regional aviation pollution. By bridging gaps in localized emission inventories and flight-phase analyses, this research supports targeted mitigation strategies, such as fleet modernization and ground operation optimization, to improve air quality in Shandong. The study highlights how sudden shifts in demand, such as those caused by pandemics, can significantly alter emission profiles, providing insights for sustainable aviation planning. Full article

To address the research gap on water-soluble heavy metals (WSHMs) in Taiyuan, China, we conducted a winter campaign (18–29 January 2019) at an urban site to measure fifteen WSHMs (Zn, Fe, Mn, Ba, Cu, Se, As, Sb, Sn, Pb, Ni, V, Ti, Cd, and Co). The mean concentration of total WSHMs (∑WSHMs) in PM_2.5 was 209.17 ± 187.21 ng m⁻³. Notably, the mass concentrations of ∑WSHMs on heavy pollution days (291.01 ± 170.64 ng m⁻³) were 224.8% higher than those on mild pollution days (89.61 ± 55.36 ng m⁻³). Principal component analysis (PCA) was applied in combination with absolute principal component score–multiple linear regression (APCS-MLR) to analyze pollution sources and their contributions. The results showed that the main sources of pollution were coal combustion and vehicle emissions (42.50%), along with the metallurgical industry and natural dust (34.47%). The carcinogenic and non-carcinogenic risks of WSHMs were assessed for both adults and children based on the United States Environmental Protection Agency’s (U.S. EPA) assessment guidelines and the International Agency for Research on Cancer (IARC) database. Children faced higher non-carcinogenic risks (hazard index = 2.37) than adults (hazard index = 0.30), exceeding the safety threshold (hazard index = 1). The total carcinogenic risk reached 2.20 × 10⁻⁵, exceeding the threshold value (1 × 10⁻⁶) for carcinogenic risk. Water-soluble arsenic (As) dominated both carcinogenic and non-carcinogenic risks in winter and was the riskiest element. These findings provide an essential basis for controlling PM_2.5-bound WSHMs in industrialized areas. Full article

Human cytomegalovirus (HCMV) is a ubiquitous betaherpesvirus that establishes lifelong latent infection in CD34⁺ haematopoietic stem and progenitor cells. A unique subset of viral genes is expressed during latency, which functions to modulate cellular mechanisms without supporting viral replication. One potential function of these genes is to regulate the differentiation state of latently infected CD34⁺ cells, thereby preventing their progression into antigen-presenting cells, e.g., dendritic cells. In this study, we first compared CD34⁺ cells that supported productive and latent infections using the RV-TB40-BAC_KL7-SE-EGFP virus. Over a seven-day time course, the proportion of latently infected CD34⁺ cell subsets within the myeloid progenitor population remained similar to that in the mock-infected control. However, starting from day 3 post-infection, there was an increase in the proportion of the early progenitor subsets, including haematopoietic stem cells (HSCs) and multipotent progenitors (MPPs). In contrast, productively infected cells, which constituted less than 1% of the population, only accounted for a small portion of the myeloid progenitors. Importantly, our data revealed that the innate immune STING/p-TBK1/p-IRF3 pathway was activated in latently infected CD34⁺ cells, yet type I interferon (IFN) expression was decreased. This decrease was attributed to impaired p-IRF3 nuclear translocation, limiting the induction of an autocrine type I IFN response. However, treatment with IFN-β could induce myelopoiesis in latently infected cells. In summary, HCMV modulates a key component of the STING pathway to inhibit antiviral immune responses by decreasing the type I IFN-mediated cell differentiation of CD34⁺ progenitor cells. This study uncovered a new mechanism of latent HCMV-mediated regulation of the host cell differentiation response. Full article

Background and Aim: Long-term treatment with biologic therapy alongside immunomAfodulators in patients with inflammatory bowel disease (IBD) can be associated with severe side effects. The objective of this study was to determine whether discontinuing anti-TNF treatment after two years in patients who have achieved mucosal healing is associated with lower relapse rates. Materials and Methods: A total of 67 patients with IBD from a single tertiary IBD Center who had achieved mucosal healing were enrolled in this retrospective study. In this single-center retrospective study (January 2014–December 2022), we screened 67 IBD patients in deep remission (endoscopic mucosal healing after ≥2 years of anti-TNF therapy). After excluding three patients without histologic data, 64 patients (25 ulcerative colitis, 39 Crohn’s disease) were analyzed. Mayo endoscopic sub-score and SES-CD were used to evaluate endoscopic activity after two years of anti-TNF therapy. Histological activity was assessed using the GHAS (for CD) and Nancy index (for UC). Results: A total of 67 patients were screened, of whom 3 were excluded due to a lack of biopsies. Of the 64 included patients, 39.06% (25/64) had UC and 60.9% (39/64) had CD, with a mean disease duration of 11.6 ± 8.0 years. All patients were in endoscopic remission at the time of therapy de-escalation, and 60.9% (39/64) also achieved histological remission (“deep remission”). In the follow-up of 38.6 months (IQR 30–48) after biologic therapy was stopped, 57.8% (37/64) relapsed with a median time to relapse of 13.5 months (IQR 8–24) off anti-TNF—a total of 34 patients required a restarting of biologic therapy. Using Spearman’s correlation, a moderate connection was observed between histological activity at withdrawal and subsequent relapse (rho = 0.467, p < 0.001). The probability of relapsing within 4 years after anti-TNF cessation was significantly higher (OR 2.72) in patients with histologically active disease at the time of de-escalation. Conclusions: Achieving ‘deep remission’ (clinical, endoscopic, and histological healing) may be a suitable parameter for making decisions on when to de-escalate therapy; however, given that over half of patients in endoscopic remission relapse after discontinuation, any de-escalation should be approached with caution and individualized patient assessment. Full article

In this work, a theoretical study on the combined effects of an external electric field and a nonresonant intense laser field on the electronic properties of a quantum dot with a truncated cone shape is presented. This quantum dot was made from a type-II CdTe/CdSe heterostructure (core/shell). Using the effective mass approximation with parabolic bands and the finite element method, the Schrödinger equation was solved to analyze the confined states of electron, hole, and exciton. This study demonstrates the potential of combining nonresonant intense laser and electric fields to control confinement properties in semiconductor nanodevices, with potential applications in optoelectronics and quantum mechanics-related technologies. Full article

HgCdSe has recently been proposed as a potential alternative material to HgCdTe for fabricating high-performance infrared detectors. This work presents a study on the growth of high-crystalline-quality HgCdSe materials on GaSb (211)B substrates via molecular beam epitaxy and demonstration of the first prototype HgCdSe-based mid-wave infrared detectors. By optimizing the MBE growth parameters, and especially the thermal cleaning process of the GaSb substrate surface prior to epitaxial growth, high-quality HgCdSe material was achieved with a record XRD full width at half maximum of ~65 arcsec. At a temperature of 77 K, the mid-wave infrared HgCdSe n-type material demonstrated a minority carrier lifetime of ~1.19 µs, background electron concentration of ~2.2 × 10¹⁷ cm⁻³, and electron mobility of ~1.6 × 10⁴ cm²/Vs. The fabricated mid-wave infrared HgCdSe photoconductor presented a cut-off wavelength of 4.2 µm, a peak responsivity of ~40 V/W, and a peak detectivity of ~1.2 × 10⁹ cmHz^1/2/W at 77 K. Due to the relatively high background electron concentration, the detector performance is lower than that of state-of-the-art low-doped HgCdTe counterparts. However, these preliminary results indicate the great potential of HgCdSe materials for achieving next-generation IR detectors on large-area substrates with features of lower cost and larger array format size. Full article

South Dongting Lake is an essential aquatic ecosystem that receives substantial water inflows from the Xiangjiang and Zishui Rivers. However, it is significantly impacted by human activities, including mining, smelting, and farming. These activities have led to serious contamination of the lake’s sediments with heavy metals (HMs). This study investigated the distribution, mobility, and influencing factors of HMs at the sediment–water interface. To this end, sediment samples were analyzed from three key regions (Xiangjiang River estuary, Zishui River estuary, and northeastern South Dongting Lake) using traditional sampling methods and Diffusive Gradients in Thin Films (DGT) technology. Analysis of fifteen HMs (Pb, Bi, Ni, As, Se, Cd, Sb, Mn, Zn, V, Cr, Cu, Tl, Co, and Fe) revealed significant spatial heterogeneity. The results showed that Cr, Cu, Pb, Bi, Ni, As, Se, Cd, Sb, Mn, Zn, and Fe exhibited high variability (CV > 0.20), whereas V, Tl, and Co demonstrated stable concentrations (CV < 0.20). Concentrations were found to exceed background values of the upper continental crust of eastern China (UCC), Yangtze River sediments (YZ), and Dongting Lake sediments (DT), particularly at the Xiangjiang estuary (XE) and in the northeastern regions. Speciation analysis revealed that V, Cr, Cu, Ni, and As were predominantly found in the residual fraction (F4), while Pb and Co were concentrated in the oxidizable fraction (F3), Mn and Zn appeared primarily in the exchangeable fractions (F1 and F2), and Cd was notably dominant in the exchangeable fraction (F1), suggesting a high potential for mobility. Additionally, DGT results confirmed a significant potential for the release of Pb, Zn, and Cd. Contamination assessment using the Pollution Load Index (PLI) and Geoaccumulation Index (Igeo) identified Pb, Bi, Ni, As, Se, Cd, and Sb as major pollutants. Among these, Bi and Cd were found to pose the highest risks. Furthermore, the Risk Assessment Code (RAC) and the Potential Ecological Risk Index (PERI) highlighted Cd as the primary ecological risk contributor, especially in the XE. The study identified sediment grain size, pH, electrical conductivity, and nutrient levels as the primary influencing factors. The PMF modeling revealed HM sources as mixed smelting/natural inputs, agricultural activities, natural weathering, and mining/smelting operations, suggesting that remediation should prioritize Cd control in the XE with emphasis on external inputs. Full article

The biological effects of nanoparticles are closely related to their intracellular content and location, both of which are influenced by various factors. This study investigates the effects of surface charge on the uptake, intracellular distribution, and exocytosis of CdSe/ZnS quantum dots (QDs) in Raw264.7 macrophages. Negatively charged 3-mercaptopropanoic acid functionalized QDs (QDs-MPA) show higher cellular uptake than positively charged 2-mercaptoethylamine functionalized QDs (QDs-MEA), and serum enhances the uptake of both types of QDs via protein corona-mediated receptor endocytosis. QDs-MEA primarily enter the cells through clathrin/caveolae-mediated pathways and predominantly accumulate in lysosomes, while QDs-MPA are mainly internalized through clathrin-mediated endocytosis and localize to both lysosomes and mitochondria. Exocytosis of QDs-MPA is faster and more efficient than that of QDs-MEA, though both exhibit limited excretion. In addition to endocytosis and exocytosis, cell division influences intracellular QD content over time. These results reveal the charge-dependent interactions between QDs and macrophages, providing a basis for designing biocompatible nanomaterials. Full article

Proper joint function has a significant impact on people’s quality of life. Joints are the point of connection between two or more bones and consist of at least three elements: joint surfaces, the joint capsule, and the joint cavity. Joint diseases are a serious social problem. Risk factors for the development of these diseases include overweight and obesity, gender, and intestinal microbiome disorders. Another factor that is considered to influence joint diseases is trace elements. Under normal conditions, elements such as iron (Fe), copper (Cu), cobalt (Co), iodine (I), manganese (Mn), zinc (Zn), silver (Ag), cadmium (Cd), mercury (Hg), lead (Pb), nickel (Ni) selenium (Se), boron (B), and silicon (Si) are part of enzymes involved in reactions that determine the proper functioning of cells, regulate redox metabolism, and determine the maturation of cells that build joint components. However, when the normal concentration of the above-mentioned elements is disturbed and toxic elements are present, dangerous joint diseases can develop. In this article, we focus on the role of trace elements in joint function. We describe the molecular mechanisms that explain their interaction with chondrocytes, osteocytes, osteoblasts, osteoclasts, and synoviocytes, as well as their proliferation, apoptosis, and extracellular matrix synthesis. We also focus on the role of these trace elements in the pathogenesis of joint diseases: rheumatoid arthritis (RA), osteoarthritis (OA), psoriatic arthritis (PsA), ankylosing spondylitis (AS), and systemic lupus erythematosus (SLE). We describe the roles of increased or decreased concentrations of individual elements in the pathogenesis and development of joint diseases and their impact on inflammation and disease progression, referring to molecular mechanisms. We also discuss their potential application in the treatment of joint diseases. Full article

Heavy metals are a major toxicological concern due to their adverse effects on human health, particularly in children exposed to contaminated areas. This study evaluated biomarkers of exposure in 253 children aged 6 to 12 from Magangue, Achi, and Arjona (Bolivar, Colombia), analyzing their relationship with neurotoxicity and hematological markers. The mean Pb concentrations at the study sites were 1.98 µg/g (Magangue) > 1.51 µg/g (Achi) > 1.24 µg/g (Arjona). A similar pattern was observed for Cd concentrations for Magangue (0.39 µg/g) > Achi (0.36 µg/g) > Arjona (0.14 µg/g). In contrast, Se concentrations followed a different trend for Arjona (0.29 µg/g) > Magangue (0.21 µg/g) > Achi (0.16 µg/g). The proportion of Se/Pb molar ratios > 1 was higher in Arjona (3.8%) than in Magangue (0.9%) and Achi (2.0%). For Se/Cd ratios, values > 1 were also more frequent in Arjona (70.7%), exceeding 20% in the other two locations. Significant differences were found among locations in red and white blood cell parameters and platelet indices. Neurotransmitter-related biomarkers, including serotonin, monoamine oxidase A (MAO-A), and acetylcholinesterase levels, also varied by location. Principal component analysis showed that Pb and Cd had high loadings on the same component as PLT, WBC, and RDW, and while Se loaded together with HGB, PDW, MCHC, MCH, and MCV, suggesting distinct hematological patterns associated with each element. Multiple linear regression analysis demonstrated a statistically significant inverse association between hair Pb levels and serotonin concentrations. Although MAO-A and Cd showed negative β coefficients, these associations were not statistically significant after adjustment. These findings highlight the potential impact of toxic element exposure on key hematological and neurochemical parameters in children, suggesting early biological alterations that may compromise health and neurodevelopment. Full article

Cadmium (Cd) toxicity destroys plant cells and affects plant growth and development. Due to its unique metallic properties, selenium (Se) has been shown to be effective in antioxidants, cellular immunity, and heavy metal detoxification. When Se and Cd are present together in plants, they antagonize. However, the mechanism of action of the two in the rice cell wall remains to be clarified. In this study, we analyzed the mechanism of Cd detoxification by rice (Oryza sativa L.) cellular polysaccharides mediated by Se, using the cell wall as an entry point. Proteomic and transcriptomic analyses revealed that “Glycosyl hydrolases family 17”, “O-methyltransferase”, and “Polygalacturonase” protein pathways were significantly expressed in the cell wall. The most abundant enzymes involved in polysaccharide biosynthesis were found, including bglB, otsB, HK, PFP, ADH1, and ALDH, which resulted in the synthetic pathway of polysaccharide formation in the rice cell wall. Finally, the essential genes/proteins, such as protein Os03g0170500, were identified. The study showed that Se inhibits Cd uptake and transport when Se (1 mg/kg) is low relative to Cd (3 mg/kg), has little inhibitory effect, and even promotes Cd (3 mg/kg) uptake when Se (5 mg/kg) is relatively high. Full article