Search Results (5,590)

The catalytic hydrogenation of carbon dioxide (CO₂) represents a transformative approach for reducing greenhouse gas emissions while producing sustainable fuels and chemicals, with ethanol being particularly promising due to its compatibility with existing energy infrastructure. Despite significant progress in converting CO₂ to C₁ products (e.g., methane, methanol), selective synthesis of C₂₊ compounds like ethanol remains challenging because of competing reaction pathways and byproduct formation. Recent advances in thermo-catalytic CO₂ hydrogenation have explored diverse catalyst systems including noble metals (Rh, Pd, Au, Ir, Pt) and non-noble metals (Co, Cu, Fe), supported on zeolites, metal oxides, perovskites, silica, metal–organic frameworks, and carbon-based materials. These studies reveal that catalytic performance hinges on the synergistic effects of multimetallic sites, tailored support properties and controlled reaction micro-environments to optimize CO₂ activation, controlled hydrogenation and C−C coupling. Mechanistic insights highlight the critical balance between CO₂ reduction steps and selective C−C bond formation, supported by thermodynamic analysis, advanced characterization techniques and theoretical calculations. However, challenges persist, such as low ethanol yields and undesired byproducts, necessitating innovative catalyst designs and optimized reactor configurations. Future efforts must integrate computational modeling, in situ/operando studies, and renewable hydrogen sources to advance scalable and economically viable processes. This review consolidates key findings, proposes potential reaction mechanisms, and outlines strategies for designing high-efficiency catalysts, ultimately providing reference for industrial application of CO₂-to-ethanol technologies. Full article

The frequency and intensity of tropical cyclones (TCs) in the Arabian Sea have increased in recent decades, heightening concerns regarding regional vulnerability and forecasting difficulties. This study examines the impact of the Madden–Julian Oscillation (MJO) on TCs activity—formation, frequency, and severity—over the Arabian Sea from 1982 to 2021. This study analyzes variations in convection, vertical wind shear (VWS), sea level pressure (SLP), and relative humidity (RH) across different MJO phases utilizing the best-track data from the India Meteorological Department (IMD), the Real-Time Multivariate MJO (RMM) index, and reanalysis datasets from the National Oceanic and Atmospheric Administration (NOAA) and the National Centers for Environmental Prediction–National Center for Atmospheric Research (NCEP–NCAR). Results show that more than 80% of TCs form during the convectively active phases of the MJO (P1–P4). These phases have the most noticeable negative outgoing longwave radiation (OLR) anomalies, as well as higher mid-level moisture and low-pressure anomalies, which are good for cyclogenesis. On the other hand, suppressed phases (P6–P8) have positive outgoing longwave radiation, dry air in the middle troposphere, and high-pressure anomalies, which make it harder for TCs to form. While VWS is predominantly favorable during both active and inactive phases, thermodynamic and convective factors principally regulate the modulation of TC activity. The simultaneous presence of active MJO phases with positive Indian Ocean Dipole (pIOD) and neutral or El Niño conditions markedly increases TC frequency, highlighting a combined influence link between interannual–El Niño–Southern Oscillation (ENSO) and IOD– and intraseasonal (MJO) variability. Additionally, the association between MJO and the Indo-Pacific Warm Pool (IPWP) reveals that TC activity peaks during convectively active MJO phases under the second twenty years of this study, emphasizing the influence of large-scale oceanic warming on TC variability. These findings underscore the critical function of the MJO in regulating TC activity variability in the Arabian Sea and stress its significance for enhancing intraseasonal forecasting and disaster preparedness in the area. Full article

Heat waves (HWs), characterized by periods of unusually high temperature, would inevitably affect the soil microenvironment and then soil respiration (Rs), which is considered to be the most active part of the global carbon cycle. An in situ spring and summer HWs simulation experiment combined with a locally common human disturbance (mowing) was conducted to separate Rs into autotrophic respiration (Ra) and heterotrophic respiration (Rh) on a natural Eurasian meadow steppe in 2018 and 2019. HWs significantly affected grassland Rs, Rh and Ra (p < 0.01) and also interacted with mowing, but the effect of spring HW and summer HW were different. During the summer HWs, daily Rs of the non-mowed plots increased by 1.07 μmol m⁻² s⁻¹ (11.71%) and increased in the mowed plots by 2.15 μmol m⁻² s⁻¹ (23.81%). During the spring HWs, daily Rs of the non-mowed plots decreased by 0.13 μmol m⁻² s⁻¹ (2.36%) and decreased by 0.52 μmol m⁻² s⁻¹ (9.02%) in the mowed plots. Rs, Rh and Ra were inhibited by spring HWs, but promoted by summer HWs. Our results indicated that the occurring time change in HWs would cause widely divergent influences on the ecosystem, and mowing would decrease the anti-interference ability of the ecosystem, which acted as an enhancement on both the positive and negative effects of HWs. These findings have important implications for accurate model prediction and carbon budget assessment. Full article

Background/Objectives: Triple-negative breast cancer (TNBC) lacks targeted therapies and has a poor prognosis. Wild ginseng (Panax ginseng) is traditionally valued for its medicinal properties, but its scarcity limits therapeutic application. Adventitious root culture technology provides a sustainable source of wild ginseng-derived bioactive compounds. This study investigated the anticancer effects of wild ginseng adventitious root extract (WGAR) on MDA-MB-231 TNBC cells and elucidated the underlying molecular mechanisms. Methods: WGAR was prepared from cultured adventitious roots of 100-year-old wild ginseng, and its chemical composition was analyzed by LC-MS/MS. Anticancer effects were evaluated using MTT assay, acridine orange/propidium iodide (AO/PI) staining, Matrigel invasion assay, Western blot analysis, and proteome profiler array. Molecular docking was performed to predict interactions between WGAR constituents and target proteins poly (ADP-ribose) polymerase (PARP)-1 and β-catenin. Results: LC-MS/MS analysis tentatively identified 17 compounds, including ginsenosides (Rg3, Rh1, Rf) and terpenoids (ursolic acid). WGAR reduced cell viability with an IC50 of 79 μg/mL at 48 h, inducing 51.2% cell death. WGAR activated the intrinsic apoptotic pathway through sequential caspase-9 and caspase-3 activation, followed by PARP cleavage, and was associated with changes in epithelial–mesenchymal transition (EMT)-related markers (reduced N-cadherin, Slug, and β-catenin) alongside decreased inhibitory Ser9 phosphorylation of GSK-3β. Proteome array analysis revealed suppression of ECM remodeling proteins (tenascin C, u-PA) and inflammatory mediators (IL-6, CXCL8). Molecular docking predicted that selected WGAR constituents, particularly terpenoid-type compounds, may potentially interact with PARP-1 and β-catenin; however, these in silico findings are hypothesis-generating and require experimental validation. Conclusions: WGAR exerts multi-target anticancer effects on TNBC cells through apoptosis induction and EMT suppression associated with modulation of GSK-3β/β-catenin signaling, suggesting its potential as a source of therapeutic agents for TNBC. Full article

Green chemistry, achieved by using water as a reaction medium, has several potential applications. In this work, a number of water-soluble Rh(III)–THP complexes, [Rh(III)Cl₃(OH)(THP)₂]⁻ (1), [Rh(III)Cl₂(OH)(THP)₃] (2), [Rh(III)Cl(OH)(THP)₄]⁺ (3), [Rh(III)Cl(OH)(en)(THP)₂]⁺ (4a), [Rh(I)(en)(THP)₂]⁺ (4b) and [Rh(III)(en)₂Cl₂]Cl (5) (where THP = P(CH₂OH)₃), were generated in aqueous media by controlling the reaction at different molar ratios of RhCl₃/THP/en (en: ethylenediamine). These complexes were fully characterized in situ by ³¹P NMR spectroscopy, base titration and by X-ray crystallography for the solid compound (4). The catalytic hydrogenation reactivities of freshly prepared complexes (1–5) were tested in situ with the selected substrate of 3,4-dimethoxystyrene under the same experimental conditions; the related catalytic reactivities are discussed in detail. Full article

Perfluorosulfonic acid (PFSA) membranes suffer from severe conductivity decay caused by dehydration at elevated temperatures, hindering their application in medium- to high-temperature proton exchange membrane fuel cells (MHT-PEMFCs). To address this, Nafion/SiO₂ composite membranes with systematically varied filler contents were fabricated via a sol–gel-assisted casting strategy to enhance hydration stability and proton transport. Spectroscopic and microscopic analyses reveal a homogeneous nanoscale dispersion of SiO₂ within the Nafion matrix, along with strong interfacial hydrogen bonding between SiO₂ and sulfonic acid groups. These interactions effectively suppress polymer crystallinity and stabilize hydrated ionic domains. Thermogravimetric analysis confirms markedly improved water retention in the composite membranes at intermediate temperatures. Proton conductivity measurements at 50% relative humidity (RH) identify the Nafion/SiO₂-3 membrane as exhibiting optimal transport behavior, delivering the highest conductivity of 61.9 mS·cm⁻¹ at 120 °C and significantly improved conductivity retention compared to Nafion 117. Furthermore, single-cell tests under MHT-PEMFC conditions (120 °C, 50% RH) demonstrate the practical efficacy of these membrane-level enhancements, with the Nafion/SiO₂-3 membrane exhibiting an open-circuit voltage and peak power density 11.2% and 8.9% higher, respectively, than those of pristine Nafion under identical MEA fabrication and operating conditions. This study elucidates a clear structure–property–transport relationship in SiO₂-reinforced PFSA membranes, demonstrating that controlled inorganic incorporation is a robust strategy for extending the operational temperature window of PFSA-based proton exchange membranes toward device-level applications. Full article

There is increasing evidence that exposure to environmental toxicants may impact fertility, especially during critical windows of reproductive axis development. Hypothalamic gonadotropin-releasing hormone (GnRH) neurons, essential for puberty onset and fertility, originate from the olfactory placode and migrate toward the hypothalamus during development, making them particularly vulnerable to environmental insults. Cadmium (Cd), a widespread heavy metal, is well known for its gonadotoxicity, but its impact on human hypothalamic neuron development remains unclear. Using human fetal GnRH neuroblasts (FNCB4) we investigated the effects of Cd exposure on their morpho-functional and developmental features. Cd induced oxidative stress and COX2 mRNA upregulation, indicative of inflammatory pathway activation, which was accompanied by reduced cell migration and downregulation of motility-related genes. These effects were associated with F-actin disassembly and altered expression of adhesion molecules. Electrophysiological analyses showed that Cd altered membrane potential, increased capacitance and permeability, and disrupted gap junctional communication, as also confirmed by connexin-43 delocalization. Moreover, Cd significantly reduced the expression of specific GnRH neuronal markers, suggesting impaired functional maturation. Overall, our findings provide the first evidence that Cd may interfere with mechanisms crucially involved in human GnRH neuron development, adding new mechanistic insights into the comprehension of how early-life exposure to Cd may contribute to fertility concerns. Full article

Halide perovskites have many advantages in environmental remediation. The photocatalytic performance of halide perovskites is often hindered by low specific surface area and rapid photogenerated carrier recombination. The aim of this work is to prepare a green, novel photocatalyst in the form of biochar-anchored Cs₃Bi₂Br₉ perovskite composites. The rose-petal-derived biomass carbon (RC) provides adsorption sites and high electrical conductivity, while the perovskite Cs₃Bi₂Br₉ can efficiently capture visible right and degrade pollutants, and the reciprocal effect can enhance the photocatalytic efficiency of the composite. The results of scanning electron microscopy (SEM) showed the Cs₃Bi₂Br₉ particles were loaded on the surface of RC. Compared with bare Cs₃Bi₂Br₉, Cs₃Bi₂Br₉/RC composite has a more perfect structure, higher specific surface area, enhanced ability to absorb visible light, and reduced bandgap value. As visible-light-driven photocatalysts, the prepared Cs₃Bi₂Br₉/RC composites can enhance the removal efficiency of Rhodamine B. The Cs₃Bi₂Br₉/RC–0.2 composite displays the highest degradation efficiencies for RhB (10 mg/L), reaching 98% within 60 min. And the rate constant (k) is 1.9 times that of bare Cs₃Bi₂Br₉. The results of electrochemical impedance spectroscopy (EIS) show that the interaction between RC and Cs₃Bi₂Br₉ speeds up charge carrier separation and transfer. During photocatalytic process, holes (h⁺) and superoxide radicals (·O₂⁻) played major roles. The composites also showed excellent stability. It is meaningful to deal with a large number of withered rose petals to make them high-value products. This work not only provides a guideline for the construction of perovskite composites materials but also shows the promising prospects of biochar composites in deep treatment for contaminated water. Full article

Objectives: This study aimed to evaluate adherence to therapy in hypoparathyroidism and related endocrine–metabolic disorders and to assess its association with biochemical outcomes, hypocalcemia episodes, and health-related quality of life (HRQoL). Methods: In accordance with PRISMA 2020 guidelines, PubMed, Scopus, Google Scholar, and the Cochrane Library were searched until September 2025. The eligible studies were randomized controlled trials, cohort, case–control studies, cross-sectional, and observational studies that reported adherence to calcium/vitamin D or recombinant parathyroid hormone therapy. Results: twenty-three studies were included in the qualitative synthesis, and 11 studies were included in the quantitative meta-analysis. Pooled medication adherence compliance was 70–82% and improved with simplified regimens and the use of recombinant PTH. Additionally, this was also associated with an improvement in HRQoL (p < 0.0001) and a lower risk of hypocalcemia (p < 0.0001). Conversely, multifactorial regulation was observed as the level of adherence had no significant effect on serum calcium levels (p = 0.7116). Sensitivity analyses demonstrate the strength of findings and indicate no significant publication bias. Conclusions: Medication adherence is a key factor in determining patient-centered outcomes in hypoparathyroidism. Better adherence is linked to a higher quality of life and fewer episodes of hypocalcemia, while its effect on biochemical parameters seems minimal. Educational programs, simple treatment regimens, and wider access to rhPTH therapy can be used to improve patient management of the disease over time. Full article

Exposure to Particulate Matter (PM) is linked to respiratory and cardiovascular diseases, certain types of cancer, and accounts for approximately seven million premature deaths globally. While governments and organizations have implemented various strategies for Air Quality (AQ) such as the deployment of Air Quality Monitoring Networks (AQMN), these networks often suffer from limited spatial coverage and involve high installation and maintenance costs. Consequently, the implementation of networks based on Low-Cost Sensors (LCS) has emerged as a viable alternative. Nevertheless, LCS systems have certain drawbacks, such as lower reading precision, which can be mitigated through specific calibration models and methods. This paper presents the results and conclusions derived from simultaneous PM₁₀ and PM_2.5 monitoring comparisons between LCS nodes and a T640X reference sensor. Additionally, Relative Humidity (RH), temperature, and absorption flow measurements were collected via an Automet meteorological station. The monitoring equipment was installed at the Faculty of Environment of the Universidad Distrital in Bogotá. The LCS calibration process began with data preprocessing, which involved filtering, segmentation, and the application of FastDTW. Subsequently, calibration was performed using a variety of models, including two statistical approaches, three Machine Learning algorithms, and one Deep Learning model. The findings highlight the critical importance of applying FastDTW during preprocessing and the necessity of incorporating RH, temperature, and absorption flow factors to enhance accuracy. Furthermore, the study concludes that Random Forest and XGBoost offered the highest performance among the methods evaluated. While satellites map city-wide patterns and MAX-DOAS enables hourly source attribution, our calibrated LCS network supplies continuous, street-scale data at low CAPEX/OPEX—forming a practical backbone for sustained micro-scale monitoring in Bogotá. Full article

Direct ethanol fuel cells (DEFCs) have gained considerable attention as promising power sources for sustainable energy conversion due to their high energy density, low toxicity, and renewable ethanol feedstock. However, the sluggish ethanol oxidation reaction (EOR) kinetics and the formation of strongly adsorbed intermediates (e.g., CO*, CH_x*) severely hinder catalytic efficiency and durability. Rhodium (Rh)-based catalysts stand out for their balanced intermediate adsorption, efficient C–C bond cleavage, and superior CO tolerance arising from their unique electronic structure. This review summarizes recent advances in Rh-based EOR catalysts, including monometallic Rh nanostructures, Rh-based alloys, and Rh–support composites. The effects of morphology, alloying, and metal–support interactions on activity, selectivity, and stability are discussed in detail. Strategies for structural and electronic regulation—such as nanoscale design, alloying modulation and interfacial engineering—are highlighted to enhance catalytic performance. Finally, current challenges and future directions are outlined, emphasizing the need for Rh-based catalysts with high activity, selectivity and stability, integrating in situ characterization with theoretical modeling. This work provides insights into the structure–activity relationships of Rh-based catalysts and guidance for designing efficient and durable anode catalysts for practical DEFC applications. Full article

The objective of this study was to determine if the use of human chorionic gonadotrophin (hCG) and ketoprofen would affect the pregnancy percentages of dairy cows following timed artificial insemination (TAI). This experiment was conducted on a commercial dairy farm in China involving 799 healthy Holstein cows (2–4 parities) between October and December 2024. Cows were randomly assigned to three groups: hCG-3 = treated with (0 d: GnRH, 100 μg; 7–8 d: PGF_2α, 0.4 mg; 52 h: GnRH, 100 μg; 14–16 h: TAI) + hCG 3 vials (300 µg)/cow on day 7 of TAI; hCG-2 group = TAI + 2 vials (200 µg) hCG/cow on day 7; and hCG+ketoprofen = TAI + 300 µg hCG/cow + ketoprofen 10 mL/cow on days 15 and 16 of TAI. Metabolomic profiling (untargeted and targeted) of 22 pregnant cows was conducted on serum collected on days 17 and 21 post-TAI. Results indicated greater pregnancy percentages in the cows of the hCG+ketoprofen-treated group compared to those in the other two groups (60.1% compared with 49.6% and 41.9%). The cows treated with hCG+ketoprofen had less oxidative stress markers, downregulation of arachidonic acid metabolism and upregulation of glycerophospholipid metabolism on day 17 after TAI, indicating that there was upregulation of tryptophan and serotonergic pathways, increased amino acid metabolism and continued anti-inflammatory effects on day 21 after TAI. These findings were confirmed by evaluation data collected by conducting the targeted metabolomic procedures, as indicated by the greater progesterone and melatonin and lesser 17-estradiol and 21-deoxycortisol concentrations. These findings indicate that combined hCG+ketoprofen administrations following the TAI treatment regimen improve pregnancy percentages in dairy cattle as a result of metabolic and endocrine milieu modulations. Full article

Infectious Bronchitis Virus is one of several major viral infections in poultry, affecting the respiratory, reproductive, and renal systems and causing significant economic losses worldwide. Current vaccines, including the H120 strain, provide limited cross-protection against emerging variants, underscoring the need for improved vaccine strategies. In this study, the complete genome of IBV H120 was divided into 12 fragments, synthesized, and assembled using the Golden Gate Assembly (GGA) method. The recombinant virus (rH120) was successfully rescued in chicken fibroblast cells and propagated in embryonated specific-pathogen-free (SPF) chicken eggs. Growth kinetics in embryonated SPF chicken eggs revealed similar replication patterns between rH120 and the original H120 strain. In broiler chickens, rH120 replicated efficiently, as confirmed by viral RNA detection in throat and cloacal swabs, and induced a stronger antibody response by 14 days post-infection. The rH120 virus proved to be genetically stable, infectious, and immunogenic, indicating that GGA-based reverse genetics is an effective system for IBV vaccine development. Full article

The six platinum group elements (PGE) are among the rarest elements in the upper continental crust of the earth. Higher values of PGE have been detected in the upper mantle and in chondrite meteorites. The PGE are siderophile and chalcophile elements and are divided into the following: (1) the Ir subgroup (IPGE) = Os, Ir, and Ru and (2) the Pd subgroup (PPGE) = Rh, Pt, and Pd. The IPGE are more refractory and less chalcophile than the PPGE. High concentrations of PGE led, in rare cases, to the formation of mineral deposits. The PGE are carried in discrete phases, the platinum group minerals (PGM), and are included as trace elements into the structure of base metal sulphides (BM), such as pentlandite, chalcopyrite, pyrite, and pyrrhotite. Similarly to PGE, the PGM are also divided into two main groups, i.e., IPGM composed of Os, Ir, and Ru and PPGM containing Rh, Pt, and Pd. The PGM occur both in mafic and ultramafic rocks and are mainly hosted in stratiform reefs, sulphide-rich lenses, and placer deposits. Presently, there are only 169 valid PGM that represent about 2.7% of all 6176 minerals discovered so far. However, 496 PGM are listed among the valid species that have not yet been officially accepted, while a further 641 are considered as invalid or discredited species. The main reason for the incomplete characterization of PGM resides in their mode of occurrence, i.e., as grains in composite aggregates of a few microns in size, which makes it difficult to determine their crystallography. Among the PGM officially accepted by the IMA, only 13 (8%) were discovered before 1958, the year when the IMA was established. The highest number of PGM was discovered between 1970 and 1979, and 99 PGM have been accepted from 1980 until now. Of the 169 PGM accepted by the IMA, 44% are named in honour of a person, typically a scientist or geologist, and 31% are named after their discovery localities. The nomenclature of 25% of the PGM is based on their chemical composition and/or their physical properties. PGM have been discovered in 25 countries throughout the world, with 64 from Russia, 17 from Canada and South Africa (each), 15 from China, 12 from the USA, 8 from Brazil, 6 from Japan, 5 from Congo, 3 from Finland and Germany (each), 2 from the Dominican Republic, Greenland, Malaysia, and Papua New Guinea each, and only 1 from Argentine, Australia, Bulgaria, Colombia, Czech Republic, England, Ethiopia, Guyana, Mexico, Serbia, and Tanzania each. Most PGM phases contain Pd (82 phases, 48% of all accepted PGM), followed, in decreasing order of abundances, by those of Pt 35 phases (21%), Rh 23 phases (14%), Ir 18 phases (11%), Ru 7 phases (4%), and Os 4 phases (2%). The six PGE forming the PGM are bonded to other elements such as Fe, Ni, Cu, S, As, Te, Bi, Sb, Se, Sn, Hg, Ag, Zn, Si, Pb, Ge, In, Mo, and O. Thirty-two percent of the 169 valid PGM crystallize in the cubic system, 17% are orthorhombic, 16% hexagonal, 14% tetragonal, 11% trigonal, 3% monoclinic, and only 1% triclinic. Some PGM are members of a solid-solution series, which may be complete or contain a miscibility gap, providing information concerning the chemical and physical environment in which the mineral was formed. The refractory IPGM precipitate principally in primitive, high-temperature, mantle-hosted rocks such as podiform and layered chromitites. Being more chalcophile, PPGE are preferentially collected and concentrated in an immiscible sulphide liquid, and, under appropriate conditions, the PPGM can precipitate in a thermal range of about 900–300 °C in the presence of fluids and a progressive increase of oxygen fugacity (fO₂). Thus, a great number of Pt and Pd minerals have been described in Ni-Cu sulphide deposits. Two main genetic models have been proposed for the formation of PGM nuggets: (1) Detrital PGM represent magmatic grains that were mechanically liberated from their primary source by weathering and erosion with or without minor alteration processes, and (2) PGM reprecipitated in the supergene environment through a complex process that comprises solubility, the leaching of PGE from the primary PGM, and variation in Eh-pH and microbial activity. These two models do not exclude each other, and alluvial deposits may contain contributions from both processes. Full article

Nine technology-related metal(loid)s (Ag, Co, Fe, Mo, Pt, Rh, Sb, Se and Y) were monitored in 137 topsoil samples from urban parks, industrial areas and gardens in Alcalá de Henares (Spain) using ICP–MS. Selenium was not detected, while Mo, Sb and Rh showed a high proportion of values below the detection limit, indicating generally low contamination. In contrast, Fe, Co and Y were detected in all samples, with industrial soils showing about two-fold higher median Co and Fe than urban soils. Garden soils displayed marked silver enrichment (median 0.439 vs. 0.068 mg kg⁻¹ in urban soils), with Ag pollution indices up to 71 and enrichment factors up to 69; around 17% of garden samples exceeded EF > 40, and more than one-quarter had EF > 10. Principal component analysis suggested a predominantly geogenic association for Co, Fe and Y and an anthropogenic component for Ag, Mo, Rh and Sb, while Pt was mainly linked to vehicular emissions. Under standard US EPA exposure scenarios applied to the 2001 topsoil concentrations, oral and inhalation hazard quotients for elements with available benchmarks remained <0.2 and inhalation cancer risks for Co were ≤2.5 × 10⁻⁷, indicating low estimated risk within the model assumptions. However, quantitative risk characterisation remains constrained by benchmark gaps for Pt and Rh and by limited consensus toxicity values for Y, which introduces uncertainty for these technology-related elements. These results should therefore be interpreted primarily as a baseline (2001) in surface soils for Alcalá de Henares rather than as a direct representation of current exposure conditions. Full article