Environmental Processes Research Articles

Discussion on “Assessing Predictability of Environmental Time Series With Statistical and Machine Learning Models” by Bonas et al.

ABSTRACTMotivated by empirical case studies and discussions of Bonas et al. (2024), this discussion paper critically examines challenges in the predictability of environmental processes, focusing on three key spheres: (a) predictability and interpretability, (b) predictability in dynamic environments, and (c) predictability into unknown spaces. These spheres highlight the responsibilities within environmetrics to ensure that predictive models, particularly advanced machine learning and deep learning methods, are applied thoughtfully. First, we discuss the trade‐off between interpretability and predictive complexity, contrasting the transparency of traditional statistical models with the “black‐box” nature of machine learning but also highlighting their enormous potential for exploiting new data sources and types. Second, we address real‐time adaptability, where models must handle concept drift and should, therefore, be continuously monitored. Finally, we consider the challenges of extrapolating predictions into unknown/nontrained areas, underscoring the risks of model overreach. This paper aims to contribute to the discussion in the field, emphasizing the critical role environmetricians play in advancing responsible, interpretable, and scientifically sound predictive practices.

Visible Light Boosted the Reduction of Cr(VI) in the Absence of Conventional Reductants in Frozen Solutions: The Overlooked Role of Inorganic Anions.

The conversion of Cr(VI) in frozen solutions is a mysterious process in the water environment. It has traditionally been believed that the reduction of Cr(VI) can only occur through interaction with traditional reducing agents like natural organic matters (NOMs) and Fe(II), with H2O merely acting as a solvent. However, this study reveals that visible light can induce the reduction of Cr(VI) by H2O even without conventional reducing agents. Specifically, within the narrow liquid-like layer between ice crystals, there is a significant increase in concentrations of protons, Cr(VI), and anions (Cl-, SO42-, and NO3-), which promotes the formation of various complexes between Cr(VI) and anions. DFT results reveal 11 types of stable Cr(VI)-anion complexes in solution, with six exhibiting visible light absorption properties. Quadrupole time-of-flight (QTOF) mass spectrometry confirms that the abundance of these six complexes (Cl-CrO2-Cl, Cr2O6-Cl, Cl-Cr2O5-Cl, Cr2O6-OSO3H, HO3SO-Cr2O5-OSO3H, and Cr2O6-ONO2) correlates with the extent to which visible light promotes Cr(VI) reduction, thus highlighting their crucial role as photoreactive intermediate complexes during this conversion process. These findings suggest that H2O in frozen solutions should no longer be regarded solely as a solvent but also as a reactant, thereby inspiring deeper insights into frozen solution chemistry.

Prevalence and contributing factors of intravenous medication administration errors in emergency departments: a prospective observational study.

Medication administration in busy emergency departments (EDs) presents significant challenges due to the high-pressure environment and complexity of processes. Medication administration errors (MAEs) are a critical concern as they can severely impact patient safety and increase healthcare costs. Understanding the prevalence and underlying factors contributing to intravenous MAEs is essential for enhancing patient care and improving hospital services. This study aims to explore and measure the frequency of intravenous MAEs in EDs and identify factors contributing to these errors during their preparation and administration. This prospective study utilised the direct observation technique where the preparation and administration of 222 intravenous medications were observed in the EDs of two hospitals in Malaysia. Information on medication preparation, administration and other procedures were recorded. Error rates were calculated and multivariable logistic regression was conducted to identify factors contributing to intravenous MAEs. MAEs were detected in 83.3% (185/222) of the observed medications affecting 86.7% (124/143) patients. Among these, a total of 240 MAEs were identified, with the most common being wrong rate of administration (55.8%), wrong preparation technique (20.8%) and omission error (11.7%). Alimentary tract and metabolism medications accounted for the highest proportion of MAEs (52.0%), followed by anti-infective medications (21.7%) and nervous system medications (15.4%). Excluding wrong time errors reduced the error rate to 80.2% (178/222). Non-verbal orders and inadequate or absence of labelling were significantly associated with MAEs, while factors such as the complexity of preparations, working shift, experience and high-alert medications showed no significant associations. The study highlighted a high prevalence of intravenous MAEs in EDs. Non-verbal orders and inadequacy in labelling of medications were significant contributing factors to MAEs in the ED. Implementing an admixture labelling policy, comprehensive training programs, strict enforcement of existing guidelines and protocols through regular audits, establishing non-punitive error reporting system, and technological solutions where financially feasible are crucial for mitigating these errors to promote patient safety.

Tailored Dynamic Seesaw Configuration of Heterojunctions to Enhance Piezo-Photocatalytic Overall Nitrogen Fixation.

Relay overall nitrogen fixation presents an intriguing approach to the simultaneous production of nitric acid and ammonia. However, it remains a significant challenge due to manipulating dual active sites on both temporal and spatial mesoscopic scales. In this study, we propose a bionic seesaw Bi4O5Cl2-Bi4O5Br2 heterojunction, which establishes a one-way reaction channel through the entanglement effect, challenging the inherent idea of synchronous reaction in a heterojunction. Notably, the adaptive interface functions as a fulcrum by incorporating both tensile Bi-Cl bonds and compressive Bi-Br bonds while also inducing the localized surface lattice distortion of Bi-O to sequentially activate the active sites. Therefore, unsaturated sites and dynamic properties trigger the seesaw structure to enhance both charge exchange and molecular polarization of N2 during reduction, thereby creating a hydroxy-rich environment for the ammonia oxidation process. Our work offers a novel active site control perspective and clarifies nitrogen fixation processes.

Hydrothermal Synthesis of Single-Crystal Europium Tungstate Hydroxide Nanobelts for Enhanced Humidity Sensing.

Humidity sensing is critical for environmental monitoring and industrial processes, yet existing sensors often struggle with sensitivity and response time. This work addresses these challenges by introducing a novel material, EuWO4(OH) nanobelts, synthesized via a hydrothermal method. These nanobelts exhibit exceptional sensing performance, with a response value of 2.3×103 at 85% RH, a rapid response time of 6.3 s, and a recovery time of 0.6 s. Unlike traditional materials, EuWO4(OH) nanobelts offer superior stability and reproducibility, making them a promising candidate for advanced humidity sensors. The unique electronic properties and high crystallinity of EuWO4(OH) nanobelts contribute to their high sensitivity and fast response, setting them apart from existing sensors. This study not only demonstrates the potential of EuWO4(OH) nanobelts for humidity sensing but also provides a new direction for the development of next-generation humidity sensors.

Stochastic Diffusive Modeling of CO₂ Emissions with Population and Energy Dynamics

Climate change, primarily driven by CO2 emissions from energy and non-energy sectors, necessitates effective mitigation strategies. This study develops a stochastic diffusive model to capture the complex dynamics of CO2 concentration, human population growth, and energy production. The objectives are to enhance the predictive accuracy of existing models by incorporating diffusion effects and stochastic variability, offering insights for sustainable environmental policies. A novel numerical scheme, an extension of the Euler-Maruyama algorithm, is proposed to solve stochastic time-dependent partial differential equations governing the model. The scheme's consistency and stability are rigorously analyzed in the mean square sense. Findings reveal that increasing emission rate coefficients in energy and non-energy sectors exacerbates CO2 levels, emphasizing the need for stringent controls. The proposed scheme demonstrates superior accuracy to the non-standard finite difference method, establishing its efficacy in modeling complex environmental processes. This research contributes a robust computational tool to improve existing predictive models, aiding decision-making for long-term ecological sustainability. By addressing uncertainties in the environmental process, the work advances the understanding of interactions between population growth, energy production, and CO2 emissions, offering a significant improvement over the traditional modeling approach. The novelty lies in integrating stochastic dynamics with diffusion to better inform CO2reduction strategies. Doi: 10.28991/ESJ-2025-09-01-012 Full Text: PDF

Heavy Mineral Analysis and Characterization of Ilmenites from the Beach Sands of Central West Coast of India

ABSTRACT Studies on heavy minerals from the estuarine beaches of Kali and Gangavali River, Central West Coast of India were conducted to understand the abundance of heavy minerals and their characterization. Higher concentrations of heavy minerals were found during monsoon followed by pre- and post-monsoon seasons. Within the sub-environments of the studied beaches, the backshore has a higher abundance compared to berm zone. The estuarine beaches of the Gangavali River show higher heavy mineral concentrations compared to the Kali estuarine beaches. Quantitative heavy mineral studies indicated that ilmenite is the dominant mineral present in the study area and shows a large spatio-temporal variability in their concentration. Ilmenites are highly altered and show three stages of alterations viz., pseudoilmenite, pseudorutile and leucoxene which indicates a progressive alteration process in the natural sedimentary environment that is attributed to the leaching of iron along with other oxides from the ilmenite lattice. The ilmenite abundance in the beach sands and their characteristics suggest a promising source for industrial minerals and have the potential for future exploitation.

Effect of Nonreactive Minerals on Acid-Etching Hydraulic Fracture Behavior and Conductivity in Carbonate Rocks

Summary Nonreactive minerals, such as quartz and talc, are frequently observed in carbonate reservoirs due to the sedimentary environment and geological processes. However, scant attention has been given by scholars to the impact of these nonreactive minerals on acid-etched fracture morphology and conductivity during acid fracturing. To clarify the acid flow and reaction behavior in carbonate rock composed of complex minerals, a mineral characterization model simultaneous for calcite, dolomite, and nonreactive minerals is first developed in this paper. Then, combined with the thermal-hydraulic-chemical coupling acid-etching model, it can study the impact of mineral content and distribution on the acid-etching fracture behavior. In addition, the acid-etching model is validated by acid-etching laboratory experiments, and the acid-fracture conductivity model is also established by testing the conductivity of rock slabs with different mineral compositions. Based on the new model, the effects of different mineral compositions on the acid flow behavior, effective acid penetration distance (EAPD), and conductivity were investigated. The research results show that the mechanism of nonreactive mineral to increase EAPD depends on the initial hydraulic fracture width, mineral distribution, and content. The acid concentration profile along the fracture length has the feature of segmentation when the circumferential flow phenomenon occurs. With the increase of the nonreactive mineral content, the EAPD increasing rate in the calcite-nonreactive mineral interaction distribution formation is faster than that in calcite-dolomite. The impact of the nonreactive mineral on conductivity is large in limestone but can be ignored in dolomite. These findings can provide guidance for the design of acid fracturing in such siliceous carbonate reservoirs.

Research note: Reduction of Salmonella enterica in simulated wastewater using electrochemical and photochemical processes.

Salmonella is a poultry-borne pathogen causing numerous human outbreaks in the U.S. Consequently, Salmonella, along with other pathogens, can be found in wastewater generated from poultry processing. It is essential to treat this wastewater before discharge, recycle, or reuse. Hence, this study investigated the utility of Advanced Oxidation Processes (AOPs) like electrochemical (EC) and photochemical processes (PC) to disinfect Salmonella in simulated wastewater (contaminated water). Three Salmonella serotypes: Kentucky (SK), Infantis (SI), and Typhimurium (ST) were chosen based on their ability to persist in poultry processing environments and cause infection. These serotypes, prepared in water at 6 to 7 Log10 CFU/mL were exposed to alternating current in EC with a voltage demand of 30 V, 40 V, and 50 V where ammonium sulfate was added as an electrolyte and ferrous sulfate to facilitate AOP production; and PC with curcumin, a photosensitizer at 0.40 % (1X) and 0.80 % (2X) to produce singlet oxygen and hydrogen peroxide that are lethal to pathogens. During the disinfection process, samples were collected every 20 min for 180 min and plated on XLD agar to assess Salmonella reduction. The data were analyzed using ANOVA in SAS. Bacterial reduction differed (P < 0.0001) between serotypes at 30 V and SK had the greatest reduction (3.13 Log10 CFU/mL), whereas there was no difference in reduction between the serotypes at 40 V (P = 0.98) where all the serotypes had more reduction than at 30 V. Complete attenuation of the serotypes was seen at 50 V (P < 0.0001), where SI reduced the most (5.96 Log10 CFU/mL) followed by ST (5.15 Log10 CFU/mL) after 140 min. SK was also attenuated (3.34 Log10 CFU/mL) after 60 min due to a lower starting concentration. This preliminary result suggests that Salmonella in poultry processing wastewater can be effectively attenuated through AOPs, offering a potential solution for enhancing poultry wastewater treatment.

A novel mathematical model for studying antimicrobial interactions against viable but non-culturable Campylobacter jejuni in the poultry product processing environment

A novel mathematical model for studying antimicrobial interactions against viable but non-culturable Campylobacter jejuni in the poultry product processing environment

EDUCAÇÃO AMBIENTAL E POLITICAS PUBLICAS: UMA REVISÃO SOBRE O PAPEL DAS POLÍTICAS NO CONTEXTO DOS DESASTRES NATURAIS

Environmental Education has been on the Brazilian political agenda since 1970, when environmental issues became an effective topic for international agencies. The analyses presented in this article show that the notion of environmental sustainability is included in the legislation and determine its introduction and debate in Brazilian education. This research is a critical analysis of the formation of concepts related to Environmental Education (EE) in Brazil, aiming to support the review of public policies in emergency situations. Thus, the premise arises that, through education, it is possible to acquire skills to prevent and deal with global risks, in addition to reimagining both politics and citizenship, promoting significant transformations in ways of thinking and lifestyle habits. In order to achieve the results, a literature review and document review were developed in order to achieve the following objective: to understand what is foreseen in Brazilian public policies regarding environmental educational processes, seeking to identify the possibilities of mainstreaming Environmental Education in disaster situations. It can be inferred that Environmental Education has an important force in the social context and in education systems, conducive to the implementation/implementation and development of public policy evaluation processes.

Seasonal distribution and environmental predictors of the movement of male blacktip sharks Carcharhinus limbatus off the US East Coast

Migrations of many marine species have shifted poleward in response to global climate change. It is imperative to gather baseline distribution data on migratory species so that these shifts can be measured and overexploitation can be avoided. Migratory species can be tracked over great distances using acoustic telemetry within cooperative networks. We reconstructed tracks from acoustic telemetry data using movement modeling and determined the seasonal distribution of male blacktip sharks Carcharhinus limbatus along the US East Coast using hot spot analyses. In addition, we modeled the environmental drivers of blacktip shark movement. We show that male blacktip sharks exhibit partial migration, and that individual migration patterns vary. The migrating population frequently migrates farther than what has been described in the scientific literature; several individuals migrated from Palm Beach County, FL, in the winter to as far north as Long Island, NY, in the summer. A smaller proportion of the population remains off southeastern Florida year-round. Male blacktip shark movements correlated with chlorophyll a and sea surface temperature in spring, photoperiod in autumn, and chlorophyll a and photoperiod in winter. Variable migration patterns likely concealed reliable predictors of movement during the summer. Like many other migratory species, the blacktip shark may have adapted photoperiod as a forecaster of environmental changes. Global climate change will affect many environmental processes but photoperiod will remain unchanged. If sharks use photoperiod as a migratory cue, they may encounter unfavorable conditions more often under climate change scenarios, which could impose stress on individuals and the population.

Extracellular Vesicles Released by Glioblastoma Cancer Cells Drive Tumor Invasiveness via Connexin-43 Gap Junctions.

Although invasiveness is one of the major determinants of the poor glioblastoma (GBM) outcome, the mechanisms of GBM invasion are only partially understood. Among the intrinsic and environmental processes promoting cell-to-cell interaction processes, eventually driving GBM invasion, we focused on the pro-invasive role played by Extracellular Vesicles (EVs), a heterogeneous group of cell-released membranous structures containing various bioactive cargoes, which can be transferred from donor to recipient cells. EVs isolated from patient-derived GBM cell lines and surgical aspirates were assessed for their pro-migratory competence by spheroid migration assays, calcium imaging, and PYK-2/FAK phosphorylation. Brain invasiveness was investigated in human cortical organoids-based assembloids and in vivo orthotopic xenografts. EV molecular features were specified by multiplex bead-based flow cytometry. Results unveil a self-sustaining mechanism triggering migration through autocrine release and engagement of a specific population of EVs of large size (L-EVs), isolated from either patient-derived cell lines or surgical aspirates. L-EVs act through modulation of calcium transients via Connexin 43-Gap Junctions (Cx43-GJ) and phospho-activation of PYK2. Pre-incubation with blocking antibodies targeting Cx43 hemichannels demonstrated a dose-dependent inhibition of the L-EV-mediated GBM migration. By exploiting patients' surgical aspirates, we show that only L-EVs deriving from tumoral cells, and not those with immune origin, promote tumor migration, impacting more prominently the tumoral cells with mesenchymal subtype. We demonstrate that L-EVs released by GBM cells, but not by the immune cells of the tumor microenvironment, represent a relevant and unique autocrine pro-migratory input for the tumor.

Investigation of Middle School Students’ Opinions and Self-Efficacy Beliefs on Mathematical Connection with Using Modelling Tasks

The purpose of this study is to determine the opinions and self-efficacy beliefs of middle school students towards mathematical connections before and after the process in a learning environment prepared in the context of connections with different disciplines and including modeling tasks. An embedded experimental mixed method design was used in the research. The study was conducted with a sum of sixty-one students in the seventh-grade experimental and control groups for fifteen weeks, including the pre-test¬, post-test, and application process. As a data collection tool, mathematical modelling tasks, mathematical connection self-efficacy scale, and pre-post opinion forms for mathematical connection were applied. It was observed that there is no statistically meaningful difference between the pre-test and post-test scores of the groups in terms of mathematical connection self-efficacy. However, after the process, it was specified that connecting mathematics with other disciplines assisted the development of students’ opinions on mathematics and different courses.

СЕЗОННОЕ СОДЕРЖАНИЕ И ИЗМЕНЧИВОСТЬ КОРТИЗОЛА У ОВЕЦ РОМАНОВСКОЙ ПОРОДЫ В ЗАПАДНОЙ СИБИРИ

The aim of research is to evaluate the nature of seasonal variations in the cortisol level in Romanov sheep in the conditions of Western Siberia. The concentration of cortisol was studied in winter and summer in purebred non-pregnant Romanov ewes aged 18 months, raised in Western Siberia. Blood serum samples were obtained from 26 sheep in winter and 34 sheep in summer. The level of cortisol in the blood serum was determined by solid-phase ELISA (reagent kit Steroid ELISA – cortisol, Alcor Bio, semi-automatic ELISA analyzer Thermo Scientific Multiskan FC). Generally accepted methods of descriptive statistics were used: the Anderson-Darling criterion was used to check the conformity of the distribution of cortisol values, the Fligner-Keelin criterion was used to assess the homogeneity of variances, and the Student's t-test was used for intergroup comparisons. The calculations were performed in the R-Studio data processing and graphics environment. The average values of cortisol in the blood serum in winter and summer periods in ewes were established, which were within the physiological norm.The level of cortisol in the summer period significantly exceeds the cortisol content in ewes in the winter period by 117.2 nmol/l (p &lt; 0.05). For Romanov sheep living in Western Siberia, reference intervals for the concentration of cortisol in the blood serum were established: in the winter from 10.5 to 122.3 nmol/l, and in the summer – from 78.5 to 286.7 nmol/l.

Selective Undercut of Undoped Optical Membranes for Spin-Active Color Centers in 4H- Silicon Carbide.

Silicon carbide (SiC) is a semiconductor used in quantum information processing, microelectromechanical systems, photonics, power electronics, and harsh environment sensors. However, its high-temperature stability, high breakdown voltage, wide bandgap, and high mechanical strength are accompanied by a chemical inertness, which makes complex micromachining difficult. Photoelectrochemical (PEC) etching is a simple, rapid means of wet processing SiC, including the use of dopant-selective etch stops that take advantage of the mature SiC homoepitaxy. However, dopant-selective PEC etching typically relies on highly doped material, which poses challenges for device applications such as quantum defects and photonics that benefit from low doping to produce robust emitter properties and high optical transparency. In this work, we develop a selective PEC process that relies not on high doping but on the electrical depletion of a fabricated diode structure, allowing the selective etching of an n-doped substrate wafer versus an undoped epitaxial (carrier density of 1(10)14 cm-3) device layer. We characterize the photoresponse and PEC behavior of the diode under bias and use those insights to suspend large (100 × 100 μm) undoped membranes of SiC. We further characterize the compatibility of membranes with quantum emitters, performing comparative spin spectroscopy between undoped and highly doped membrane structures, finding the use of undoped material improves ensemble spin lifetime by >5×. This work enables the fabrication of high-purity suspended thin films suitable for scalable photonics, mechanics, and quantum technologies in SiC.

Environmental Licensing in Mozambique: Why is it Important to Consider Creating a Database and Ensuring Improved Social Participation?

Objective: The aim of this study was to identify possible gaps and opportunities in Mozambique's environmental legislation in order to point out opportunities for optimizing the environmental regularization of enterprises and activities that degrade the environment. Theoretical Framework: In this research we list the main opportunities for improvement in Mozambican environmental legislation on the licensing of projects, based on global experiences. Thus, we studied the main environmental laws in force in the country and sought to draw from them the following key aspects: institutions that intervene in the licensing process, guidelines, government databases, integration between planning instruments, types of environmental licenses, environmental impact assessment, strategic environmental assessment, environmental compensation, duration of the process, and the participation of society during environmental audits. Method: This study was based on a descriptive documentary analysis, according to the methodology of Gil (2002). The following steps were followed: identification of normative instruments, survey of key issues, comparison with the practices of other countries, and, finally, outlining aspects for potential improvement, taking into account the legislation in application in the G7 and BRICS. Results and Discussion: Our results indicated that, in general terms, Mozambican legislation does not differ from that applied in the G7 and BRICS countries in regards to the involvement of various institutions in environmental licensing, the existence of guidelines, the application of environmental impact assessment, environmental compensation, and the participation of society. In this sense, we discuss opportunities for improvements to be implemented in Mozambican public policies. Research Implications: The practical and theoretical implications of this research are discussed, providing insights into how the results can be applied or influence the analysis time of the environmental regularization licensing process. We also observed the lack of a database available for public access, the absence of strategic environmental assessment, and the lack of integration between planning instruments in current legislation. The lack of these instruments contributes to possible environmental and socio-economic liabilities. Originality/Value: This study contributes to the literature by explaining the importance of creating and implementing a robust and intelligent database available for public access on a geospatial platform. It also contributes to the inclusion of public participation, both in person and online, in public hearings on the environmental regularization of projects and their respective activities that cause environmental, social, and economic impacts when not assessed and mitigated.

МОДЕЛИРОВАНИЕ МНОГОУРОВНЕВОЙ ДИНАМИКИ УРОЖАЙНОСТИ СЕЛЬСКОХОЗЯЙСТВЕННЫХ КУЛЬТУР

The objective of the study is to develop an algorithm for modeling crop yields based on the dynamic-stochastic and cyclical properties of long-term characteristic series. Tasks: identifying the properties of time series of agricultural crop bioproductivity based on their consideration as multi-level structures with cyclical fluctuations; using the properties of variability of long-term characteristic series to build forecasting or stochastic assessment models; implementing the modeling algorithm using the example of grain and leguminous crop yields in Russia and wheat bioproductivity in the USA. The object of the study is long-term variability of agricultural crop yields. An algorithm for constructing a dynamic-stochastic multilevel model for forecasting the variability of agricultural crop yields under different conditions of a combination of the state of the natural environment and technological processes, taking into account cyclical fluctuations of the characteristic, has been created. The algorithm has been implemented for modeling empirical series. When describing the long-term variability of the characteristic and assessing favorable and unfavorable events, trends, histograms of the distribution of relative frequencies of local minimum and maximum cycles, and probability distributions of yield losses and gains have been used. Multilevel modeling allows assessing the dynamics of agricultural crop bioproductivity under different conditions of producers' activities: determining losses in unfavorable conditions of the natural and technological environment, identifying yield gains in favorable situations. Using stochastic methods, it is proposed to estimate rare events corresponding to very high and very low crop yields, as well as transitions of series levels into events. Based on the identified multi-level trends and the frequency of local extreme cycles, a retrospective forecast of the characteristic with a lead time of 3 years is obtained.

Radon on Mars and the Moon derived from Martian and lunar meteorites

The radioactive gas radon-222, a fluid and aerosol tracer in Earth’s lithosphere and atmosphere, can also reveal subtle rock physics processes in extraterrestrial environments, such as those involving water, but remains poorly constrained in planetary bodies due to the limited number of samples available. Here we measure the effective radium-226 concentration (ECRa) of six Martian and nine lunar meteorites to derive radon source terms for Martian and lunar rocks. ECRa values are 0.029–0.78 and 0.045–0.80 Bq kg−1 for Martian and lunar meteorites, respectively (0.041 ± 0.003 Bq kg−1 for falls and 0.28 ± 0.02 Bq kg−1 for finds), lower than most terrestrial rocks but similar to other meteorites and terrestrial primitive basalts. The effect of terrestrial alteration on ECRa and its temperature sensitivity are also determined experimentally. Radon emanation coefficient values are 2.1–17% (mean: 8.1 ± 2.5%) for Martian meteorites and 0.43–11% (mean: 5.5 ± 1.0%) for lunar meteorites. Mean estimated surface radon fluxes for Mars and the Moon are 0.16–0.60 and 0.33–0.44 mBq m−2 s−1 (78–280 and 160–210 atoms m−2 s−1), respectively, much lower than on Earth (21 mBq m−2 s−1 or 104 atoms m−2 s−1). Our meteorite analyses constrain radon emanation on Mars and the Moon and provide a basis for current and future in-situ measurements.

Bio-mediated synthesis of nanoparticles: A new paradigm for environmental sustainability

The synthesis of nanoscale metals and non-metals is an intriguing subject, and the green synthesis of nanoparticles (NPs) is increasingly utilized across various sectors, including environmental science, agriculture, engineering, and food processing. Traditionally, the production of nanoscale materials relies heavily on physical and chemical processes, which can lead to significant challenges such as high energy consumption and environmental contamination. Poor management of agricultural and industrial waste contributes to greenhouse gas emissions, exacerbates climate change and disrupts ecosystems. Conversely, green nanotechnology offers a safer alternative by leveraging biological materials, that inherently provide capping and reducing agents. This approach is not only more cost-effective but also results in lower pollution levels, thereby enhancing environmental safety. Green synthesis involves the reduction of metallic and non-metallic atoms using plant extracts, microorganisms, and agricultural waste instead of conventional harmful substances. The bioactive compounds, including flavonoids, alkaloids, tannins, and saponins, play a critical role in the bioreduction of metals and the production of nanoparticles. There has been the increasing interest in utilizing these biological sources for green nanoparticle production over the past decade from their potential to serve as economical and environmentally friendly alternatives. Overall, green nanotechnology demonstrates its potential to revolutionize industries and pave the way for a more sustainable and resilient future.