In natural water bodies, numerous cyanobacteria have the potential to intracellularly synthesize cyanotoxins, among which microcystin (MC) is the ubiquitous toxin that has been well known to be carcinogenic for hepatocytes. MC synthesis is a complex process, which involves about 10 non-ribosomal proteins encoded by the mcy gene cluster. In the natural environments containing MC-producing cyanobacteria, a variety of external factors can affect the generation of MC by mediating the expression of synthesizing genes. These factors can be generally divided into biotic factors (e.g., daphnia, virioplankton, MC-degrading bacteria, algicidal bacteria) and abiotic factors (e.g., nutrients, physical factors, chemicals, phytochemicals, essential trace elements), which are of great significance to the effective reduction of MC. Furthermore, comparison of MC-synthesizing genes in different cyanobacterial strains was performed, and the related factors affecting MC synthesis were summarized. Then, the problems and gaps regarding the biological effect of exogenous factors on microcystin synthesis were discussed. This review article may provide new ideas for addressing the challenges and bottlenecks of MC management.

Few studies have documented the air quality, noise, thermal comfort, and health risk assessment of household kitchens related to Sub-Sahara Africa. In this paper, air quality (CO and PM₂.₅), thermal comfort (relative humidity (RH) and temperature), noise, and health risk in urban household kitchens with kerosene-fueled stoves were presented. This study was carried out during the dry season (summer) in the Southwestern part of Nigeria. At the breathing zone, PM₂.₅ and CO concentrations in the assessed kitchens were measured. In addition, the noise level, RH, and air temperature in the assessed kitchens were also determined. Furthermore, an evaluation of the heat index and health risk of the exposed population to the kerosene-fueled stove kitchens was carried out. During cooking, average CO and PM₂.₅ concentrations were 24.77 ± 1.05 ppm and 138.10 ± 2.61 µg/m³, respectively, while the RH was 68.34 ± 0.73%, noise level was 51.14 ± 1.08 dB, and temperature was 29.86 ± 0.23 °C. The CO and noise levels were relatively slightly lower and PM₂.₅ was significantly higher than the thresholds recommended by World Health Organisation. In most of the kitchens, the heat index evaluation revealed the possibility of heat exhaustion, heat cramps, and sunstroke with prolonged exposure of the vulnerable group. The air quality index depicted unhealthy (CO exposure) and very unhealthy (PM₂.₅ exposure) while the hazard quotient (> 1) implied possible health risk concerning exposure by inhalation. Better design of kitchen with adequate ventilation and improved stoves are suggested.

To monitor groundwater salinization due to seawater intrusion (SWI) in the aquifer of the eastern Nile Delta, Egypt, we developed a predictive regression model based on an innovative approach using SWI indicators and artificial intelligence (AI) methodologies. Hydrogeological and hydrogeochemical data of the groundwater wells in three periods (1996, 2007, and 2018) were used as input data for the AI methods. All the studied indicators were enrolled in feature extraction process where the most significant inputs were determined, including the studied year, the distance from the shoreline, the aquifer type, and the hydraulic head. These inputs were used to build four basic AI models to get the optimal prediction results of the used indicators (the base exchange index (BEX), the groundwater quality index for seawater intrusion (GQISWI), and water quality). The machine learning models utilized in this study are logistic regression, Gaussian process regression, feedforward backpropagation neural networks (FFBPN), and deep learning-based long-short-term memory. The FFBPN model achieved higher evaluation results than other models in terms of root mean square error (RMSE) and R² values in the testing phase, with R² values of 0.9667, 0.9316, and 0.9259 for BEX, GQISWI, and water quality, respectively. Accordingly, the FFBPN was used to build a predictive model for electrical conductivity for the years 2020 and 2030. Reasonable results were attained despite the imbalanced nature of the dataset for different times and sample sizes. The results show that the 1000 μS/cm boundary is expected to move inland ~9.5 km (eastern part) to ~10 km (western part) to ~12.4 km (central part) between 2018 and 2030. This encroachment would be hazardous to water resources and agriculture unless action plans are taken.

Under the influence of large water conservancy projects and seasonal precipitation, the groundwater levels along rivers and lakes show cyclic patterns of change. Thus, the fluctuation in water level is an important factor affecting the particle migration and deposition characteristics in the sand layers considered in projects such as groundwater recharge projects. Existing theories all treat the recharge aquifer as saturated, making it difficult to elucidate the mechanism of groundwater source heat pump recharge blockage in river and lake coastal areas. An extensive laboratory study was conducted here to assess the effect of water level changes on the deposition characteristics of particle migration in porous media. A one-dimensional sand layer migration-deposition test system was used to test particle transport and deposition characteristics at different water levels. The tests were carried out for two combinations of particle sizes at four water levels (110 mm, 220 mm, 330 mm, and 440 mm) and three seepage velocities (0.024 cm/s, 0.047 cm/s, and 0.071 cm/s). The results show that when the seepage velocity is kept constant and the water level is low, the particles flow through fewer pore channels, and as the water level increases, the particle flow through pore channels increases accordingly, so the particles are more easily deposited in the pore channels. This is ultimately reflected in the decrease in the peak relative concentration [Formula: see text] and the increase in the pore volume ratio [Formula: see text]. When the water level remains constant, the hydrodynamic effect gradually becomes stronger as the seepage velocity increases, and the originally deposited particles may break away from the surface of the deposit and flow out with the water, resulting in a higher suspended particle concentration of the effluent and a higher [Formula: see text]. Smaller particles are more affected by the hydrodynamic effect than larger particles.

In this research, one-step synthesis of redox co-precipitation method (using sodium lauryl sulfate, KMnO₄, and metal precursor) was well applicable in universally preparing low-dimensional Me-MnOx nanosheet catalysts with different metal doping (Me=Co, Ni, or Sn). NH₃-SCR activity was explored to the relationship with structure morphology and physio-chemical properties via the characterization techniques of SEM, XRD, XPS, H₂-TPR, and NH₃-TPD. It was found that Ni-MnOx has a relatively poor activity at low-down temperature but was improved as the reaction temperature rising. Co-MnOx presented a relatively stable catalytic activity of which the NOx conversion rate can be maintained 80~90% in a wide temperature window of 100–250 °C with relatively better N₂ selectivity. Compared with Co- or Ni-modified MnOx, Sn-MnOx catalyst has an excellent low-temperature catalytic activity (93% NOx conversion at 100 °C) that was maintained > 80% before 200 °C but with poor selectivity to N₂. Due to its nanosheet-structured solid solution structure, Sn-MnOx promoted the interaction between MnOx and SnO₂ with the increased contents of adsorbed oxygen and also the numbers of surface Lewis acid sites, which integrally promoted the NH₃-SCR reaction at low temperature and also contributed to an acceptable resistances to water and sulfur. High content of adsorbed oxygen was beneficial to improve the catalytic activity at lower temperatures, while the electron cycle interaction of different metal valence ions will play a more important role with the increase of reaction temperature.

Over the past few years, a growing number of scholars have explored environmental deterioration and its connection to various indicators acting as proxies for growth and globalisation. Taking this into view, the current study examines the globalisation-environment nexus, using 66 major countries and administrative regions of the Belt and Road Initiative (BRI) as case studies for 2000–2015. For this analysis, six biophysical resource usages were used within the safe operating space of the planetary boundary concept as proxies for the environmental state, along with the four main and five sub-indices of the Konjunkturforschungsstelle (KOF) globalisation index. Pearson’s correlation, hierarchical clustering, redundancy analysis, linear regression, autoregressive integrated moving average (ARIMA) forecasting, etc. were used to infer existing trends, the interactions between the environment and globalisation, a projected future, and coupling with safe operating space aspects. The findings reveal the long-run asymmetric relationship of variables. Surpassing safe operating limits to achieve globalisation is the most prominent outcome. Economic, trade, and financial globalisation are more crucially related to biophysical resource usage. Nitrogen use and material footprint act as strong drivers for various indices of globalisation. At least 40% of countries are above the global average resource usage and 50% have crossed all of the safe operating limits. At the present rate, nearly 51% of countries might cross all their safe operating spaces in 2030. In a race to achieve more globalisation (0.95), more than 30% of countries might cross 5 of the 6 planetary boundaries. Land system change, the biogeochemical cycle, and climate change are impending as the most important domains to be focused on regarding globalisation. Based on the findings, it can be recommended that governments and policymakers devote more attention to reframing and redesigning globalisation to be more environment friendly to achieve long-term sustainable development goals.

The agriculture sector remains under attack by the consistent flooding events in Pakistan as flooding water is sweeping away crops and livelihood opportunities, thus dragging the already vulnerable communities into poverty. This research has studied the adverse impacts of consistent floods (2010 to 2018) on the rural mountainous agriculture, agrarian occupation, economic system, and rise in poverty in ten districts of Hazara and Malakand divisions, Khyber-Pakhtunkhwa province, Pakistan. In total, 1000 self-administered questionnaires were deployed at the household level through judgment sampling studying the flood-affected households. Primary data for the impacts of floods on the livelihood, economic status, and poverty and correlation among them was estimated through three parallel logistic regression equations based on indexes for three separate models for the study variable to describe the flood-induced vulnerability at HH level. The results of the interrelationship of the selected variables declared Malakand division more prone to loss of livelihood, degradation of low-economic status, and increased in poverty due to flooding than Hazara division. It is concluded that floods have curtailed the agricultural livelihood on damaging crop production that has degraded locals’ economic system by reducing household’s income and savings, ending up in borrowing of money and leading to debt due to non-repayment. Households’ vulnerability has increased due to increased poverty as being more exposed to natural disasters. It calls for government intervention to safeguard poor mountainous communities of Pakistan through financial help, seeds, livestock, and technical help in times of disaster.

With the rapid development of modern agriculture, non-point source nitrogen pollution from higher polluting farms has become one of the main contributions to the eutrophication of the watershed. This paper first constructed a tripartite evolutionary game model concerning local governments, higher polluting farms, and consumers, all of which participate in the reduction of nitrogen pollution in the river basin. Secondly, the evolution process of evolutionary stability strategy (ESS) and the impact of critical parameters on the strategies of the three stakeholders were analyzed through numerical simulation. The results demonstrated that (1) six ESSs of the system are determined, only (1, 0, 1) is regarded as the most ideal ESS: regulation by local governments, higher polluting farms adopting not purchasing emission rights, and consumers purchasing green agricultural products. (2) The regulation strategy of local governments depends on comparing political losses with the sum of emission reduction subsidies and the supervision cost. (3) The marginal abatement costs, the price of nitrogen emission permits, nitrogen use efficiency, and the subsidy standard for unit emission reduction are the main factors that affect the ESS of higher polluting farms. (4) The ESS of consumers is significantly affected by low-nitrogen preference, government subsidies, and nitrogen use efficiency. This study suggests that the government should strengthen the supervision of the watershed environment from the aspects of improving the market mechanism of nitrogen trading, establishing a dynamic monitoring system, and innovating a subsidy mechanism.

Legionella pneumophila (L. pneumophila) is one of the main pathogens, causing pneumonia and respiratory tract infections, especially in patients with ventilator-associated pneumonia (VAP). This study aimed to approve the hypothesis that the serogroup distribution of L. pneumophila isolates from patients is correlated with Legionella strains in the environment. A total of 280 bronchoalveolar lavage (BAL) samples from VAP patients admitted to the intensive care unit (ICU) as well as 116 water samples from different sources in four hospitals in Tehran, Iran, were evaluated for the presence of L. pneumophila infection by culture, nested polymerase chain reaction (PCR), real-time PCR, and sequencing for genetic diversity. The molecular and culture methods found 24 (8.6%) and 5 (1.8%) samples to be positive for L. pneumophila in VAP patients, while they found 23 (19.8%) and 8 (6.9%) positive samples in water resources, respectively. The sequencing results indicated that all positive clinical samples and 14 (60.8%) environmental samples were belonged to L. pneumophila serogroup 1. Smoking, age, length of ICU stay, and duration of ventilator use had strong relationship with L. pneumophila infectivity. In conclusion, this is the first report from Iran to determine minor differences in the serogroup distribution of environmental and clinical strains. However, further studies are needed to confirm this relationship in different regions of Iran.

The research on land use transformation has attracted more and more attention, and there are few research results on the eco-environmental effects of regional land use change from the perspective of land use function transformation. From the perspective of production-living-ecological land use function classification, this paper obtained land use change data of Shaanxi Province in 2000, 2010, and 2020, calculated the land use transfer matrix, ecological environment quality index, and ecological contribution rate of land use transformation, and quantitatively analyzed the temporal and spatial evolution of production-living-ecological spaces and the eco-environmental effects of land use structure transformation in Shaanxi Province. The results showed that the land use change in Shaanxi Province is mainly manifested in the continuous increase of ecological and living land area and the continuous decrease of production land area from 2000 to 2020. In the transformation of land use structure in Shaanxi Province, the biggest change in area is the mutual transformation between productive cultivated land and ecological grassland land. The occupation of ecological grassland land by other land types is an important factor leading to the decline of ecological environment quality. Overall, the ecological environment of Shaanxi Province has shown a trend of improvement in the past two decades. Quantitative research on the transformation characteristics of land use structure and its ecological environment effects in the past two decades is conducive to providing data support for the promotion of ecological civilization construction in Shaanxi Province.