Exploring the antioxidant potential of nekemias species extracts on edible oils: In vitro assessment and lipid oxidation inhibition.

Synthetic antioxidants have long been used to protect edible oils from oxidation. However, concerns about their potential health risks and environmental impact have led to a growing interest in natural antioxidants. In this study, we explore the antioxidant properties of extracts from four Nekemias plant species: Nekemias grossedentata (AGR), Nekemias megalophylla (AME), Nekemias chaffanjonii (ACH), and Nekemias cantoniensis (ACA) by obtaining the values for different tests. We investigate their bioactive compound content and evaluate their antioxidant capabilities on six edible oils categorized into three lipid systems based on their fatty acid compositions: oleic acid, linoleic acid, and linolenic acid. Our findings demonstrate that AGR and AME extracts, rich in bioactive compounds, exhibit strong antioxidant activities in vitro, effectively inhibiting lipid oxidation, especially in oleic acid-rich oils like camellia oil. The antioxidant effects of these extracts are comparable to synthetic antioxidants such as TBHQ and superior to natural antioxidant Tea Polyphenols (TP). While the extracts also show antioxidant potential in linoleic and linolenic acid systems, the stability of their effects in these oils is lower than in oleic acid system. These results suggest that Nekemias species extracts have the potential to serve as natural additives for extending the shelf life of edible oils, contributing to the exploration of natural antioxidants.

A rapid and low-cost platform for detection of bacterial based on microchamber PCR microfluidic chip.

Polymerase chain reaction (PCR) has been considered as the gold standard for detecting nucleic acids. The simple PCR system is of great significance for medical applications in remote areas, especially for the developing countries. Herein, we proposed a low-cost self-assembled platform for microchamber PCR. The working principle is rotating the chamber PCR microfluidic chip between two heaters with fixed temperature to solve the problem of low temperature variation rate. The system consists of two temperature controllers, a screw slide rail, a chamber array microfluidic chip and a self-built software. Such a system can be constructed at a cost of about US$60. The micro chamber PCR can be finished by rotating the microfluidic chip between two heaters with fixed temperature. Results demonstrated that the sensitivity of the temperature controller is 0.1℃. The relative error of the duration for the microfluidic chip was 0.02 s. Finally, we successfully finished amplification of the target gene of Porphyromonas gingivalis in the chamber PCR microfluidic chip within 35 min and on-site detection of its PCR products by fluorescence. The chip consisted of 3200 cylindrical chambers. The volume of reagent in each volume is as low as 0.628 nL. This work provides an effective method to reduce the amplification time required for micro chamber PCR.

PM-bound polycyclic aromatic compounds (PACs) in two large-scale petrochemical bases in South China: Spatial variations, sources, and risk assessment.

Polycyclic aromatic compounds (PACs) are potential pollutants emitted from the petrochemical industry, whereas their occurrence and sources in petrochemical regions are still poorly known. The present study revealed the spatial variations, compositional profiles, sources and contributions, and health risks of PM-bound PACs in two large-scale petrochemical bases (GDPB and HNPB) in South China. The concentrations of parent polycyclic aromatic hydrocarbons (PAHs) were 7.14 ± 3.16 ng/m3 for ∑18PAHs and 0.608 ± 0.294 ng/m3 for the PAHs with molecular weight of 302 amu (MW302 PAHs) in the GDPB base and 2.55 ± 1.26 ng/m3 and 0.189 ± 0.088 ng/m3 in the HNPB base. Oxygenated PAHs (OPAHs) showed comparable concentrations to the parent PAHs in both the bases and nitrated PAHs (NPAHs) had the lowest mean levels (260 pg/m3 and 59.4 pg/m3 in the two regions). Coronene, 2,8-dinitrodibenzothiophene, and dibenzo[a,e]fluoranthene showed remarkably higher contributions to the PAC and can be PAC markers of the petrochemical industry source. Five sources of PACs were identified respectively in both petrochemical bases by the positive matrix factorization (PMF) model. The vehicle (and ship) traffic exhaust was the primary source of PACs (contributed 33% to the ∑PACs), and the sources related to the coking of coal and heavy petroleum and refinery exhaust were identified in both bases, with contributions of 10-20%. PACs in GDPB also contributed from secondary atmospheric reactions (17.3%) and the usage of sulfur-containing fuels (20.9%), while the aromatics industry made a significant contribution (20.1%) to the PACs in the HNPB region. The cumulative incremental lifetime cancer risks (ILCRs) induced by inhalation of PM-bound PACs in both petrochemical bases were low (10-8-10-6). For the sources related to the petrochemical industry, coking activities and the aromatic industry were the significant contributors to the ∑ILCRs in GDPB and HNPB, respectively. This research has implications for further source-targeted control and health risk reduction of PACs in petrochemical regions.

The significance of spread through air spaces in the prognostic assessment model of stage I lung adenocarcinoma and the exploration of its invasion mechanism.

PURPOSE: Spread through air spaces (STAS) is a crucial invasive mode of lung cancer and has been shown to be associated with early recurrence and metastasis. We aimed to develop a prognostic risk assessment model for stage I lung adenocarcinoma based on STAS and other pathological features and to explore the potential relationship between CXCL-8, Smad2, Snail, and STAS. METHODS: 312 patients who underwent surgery at Harbin Medical University Cancer Hospital with pathologically diagnosed stage I lung adenocarcinoma were reviewed in the study. STAS and other pathological features were identified by H&E staining, and a prognostic risk assessment model was established. The expression levels of CXCL8, Smad2, and Snail were determined by immunohistochemistry. RESULTS: The nomogram was established based on age, smoking history, STAS, tumor lymphocyte infiltration, tissue subtype, nuclear grade, and tumor size. The C-index for DFS was (training set 0.84 vs validation set 0.77) and for OS was (training set 0.83 vs validation set 0.78). Decision curve analysis showed that the model constructed has a better net benefit than traditional reporting. The prognostic risk score validated the risk stratification value for stage I lung adenocarcinoma. STAS was an important prognostic factor associated with stronger invasiveness and higher expression of CXCL8, Smad2, and Snail. CXCL8 was associated with poorer DFS and OS. CONCLUSIONS: We developed and validated a survival risk assessment model and the prognostic risk score formula for stage I lung adenocarcinoma. Additionally, we found that CXCL8 could be used as a potential biomarker for STAS and poor prognosis, and its mechanism may be related to EMT.

PM2.5-bound phthalates and phthalate substitutes in a megacity of southern China: spatioseasonal variations, source apportionment, and risk assessment.

Plasticizers are ubiquitous pollutants in the environment, whereas few efforts have been made to elucidate their emission sources in the atmosphere. In this research, the spatioseasonal variations and sources of particle-bound (PM2.5) phthalates (PAEs) and their substitutes (APs) at residential sites in seven districts and at four potential point-source sites across a megacity in South China were revealed. The total concentrations of PAEs ranging from 10.7 to 528 ng/m3 were substantially higher than those of APs (1.45.58.5 ng/m3). Significant spatial variations in the concentrations of the pollutants were observed, which were generally higher at the sites with intensive industrial activities and the point-source sites. Most atmospheric plasticizer levels peaked in summer, probably due to the temperature-promoted volatilization. Seven sources of plasticizers were identified by the positive matrix factorization (PMF) model. The sources in less industrialized districts are mainly associated with domestic and commercial emissions and with industry in the industrialized districts. Specifically, plastics and personal care products together contributed 60% of the plasticizers in the atmosphere of this city, followed by solvents and polyester industry sources. The incremental lifetime cancer risk of inhalation exposure to bis(2-ethylhexyl) phthalate in the study city is below the acceptable level. Relatively higher risks were found for residents living around sites with intensive industrial activities and around wastewater treatment plant.

Surface mining caused multiple ecosystem service losses in China.

China's surface mining greatly supported the rapid socio-economic development; however, there was a scarcity in the systematic understanding of national changes in surface mining changes and associated ecosystem services (ESs) losses, which inevitably affected human well-being and limited sustainable ecosystem management and policy optimization. In this study, we quantified the areal changes in surface mining based on the ChinaCover database and performed further analysis of ES loss from expanded surface mining using multidimensional geospatial data from 1990 to 2015, including MODIS products, meteorological records, and statistical datasets. Our observations reveal that China's surface mining was estimated to be 4746 km2 in 2015 and that Inner Mongolia had the largest surface mining area (28%). Surface mining expanded remarkably from 1990 to 2015, with an increase by 2.7 times after 2000. In particular, Inner Mongolia, Shanxi, and Qinghai had the greatest increases in surface mining area. Rapid expansion of surface mining led to obvious declines in natural habitat area, water retention, net primary productivity, and grain production, and these ES losses showed apparent spatiotemporal variations. China has taken many measures to reclaim the abandoned surface mining sites. Given the rapid expansion of surface mining and related ES loss, China should continue to perform ecological restoration for its sustainability.

Brominated flame retardants and heavy metals in common aquatic products from the pearl river delta, south china: Bioaccessibility assessment and human health implications.

Aquatic products are an important source of environmental pollutants to humans. This study was conducted to assess the bioaccessibility of selected brominated flame retardants and heavy metals in common aquatic products from the Pearl River Delta, South China, as well as associated human health risks. Based on a questionnaire survey, ten of the most consumed aquatic products were collected from local markets. The bioaccessibility of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDDs), and heavy metals was assessed using an in vitro gastrointestinal model. Bioaccessibility of heavy metals (33.0-84.0%) and HBCDDs (38.5-68.4%) was significantly higher than that of PBDEs (13.4-65.4%). Total non-carcinogenic and carcinogenic risks from heavy metal consumption were much higher than the threshold values due to excessive abundances of arsenic in shellfish (HQ = 2.45, CR = 1.1 ×10-3). Furthermore, middle-aged populations and females were subjected to greater health risks due to different intakes of aquatic products among age and gender groups. Significant difference in bioaccessibility among analytes indicated that bioaccessibility of pollutants is non-negligible in health risk assessment. This is the first study systematically investigating health risks of aquatic products consumption and concludes that shellfish is a great cause for concern for the PRD residents.

Polybrominated diphenyl ethers in indoor air from two typical E-waste recycling workshops in Southern China: Emission, size-distribution, gas-particle partitioning, and exposure assessment.

The emission characteristics of respirable particulate matter (PM10), and polybrominated diphenyl ether (PBDE) size distribution, gas-particle partitioning and occupational exposure in two e-waste recycling workshops (manual and thermal dismantling workshop: ManuDW and TherDW) were investigated. The PM10 mass concentration was higher but the number concentration was lower in the ManuDW than in the TherDW. The gaseous phase PBDE concentration (40.5 ng/m3) was higher in the ManuDW than in the TherDW (10.6 ng/m3) while the particulate phase PBDE concentration was just reverse (57.7 vs 156 ng/m3). The size distribution of particle was similar for two workshops but the size distribution of particle-bound PBDE exhibited remarkable differences. BDE-209 was the dominant congener in particle-bound PBDE in the TherDW, while Tri-, Tetra-, and Deca-BDE were the three most abundant homologues in the ManuDW. The size distribution of particle-bound PBDE homologue profile in the ManuDW was also distinct from that in the TherDW. The PBDE exposure doses were 13.9 and 15.3 ng/kg/day in the ManuDW and the TherDW, far lower than reference doses. Gaseous and particle phase have same contribution to the total doses in the ManuDW but the exposure doses in the TherDW mainly come from the particle phase.

Thermomass Theory in the Framework of GENERIC.

Thermomass theory was developed to deal with the non-Fourier heat conduction phenomena involving the influence of heat inertia. However, its structure, derived from an analogy to fluid mechanics, requires further mathematical verification. In this paper, General Equation for Non-Equilibrium Reversible-Irreversible Coupling (GENERIC) framework, which is a geometrical and mathematical structure in nonequilibrium thermodynamics, was employed to verify the thermomass theory. At first, the thermomass theory was introduced briefly; then, the GENERIC framework was applied in the thermomass gas system with state variables, thermomass gas density ρh and thermomass momentum mh, and the time evolution equations obtained from GENERIC framework were compared with those in thermomass theory. It was demonstrated that the equations generated by GENERIC theory were the same as the continuity and momentum equations in thermomass theory with proper potentials and eta-function. Thermomass theory gives a physical interpretation to the GENERIC theory in non-Fourier heat conduction phenomena. By combining these two theories, it was found that the Hamiltonian energy in reversible process and the dissipation potential in irreversible process could be unified into one formulation, i.e., the thermomass energy. Furthermore, via the framework of GENERIC, thermomass theory could be extended to involve more state variables, such as internal source term and distortion matrix term. Numerical simulations investigated the influences of the convective term and distortion matrix term in the equations. It was found that the convective term changed the shape of thermal energy distribution and enhanced the spreading behaviors of thermal energy. The distortion matrix implies the elasticity and viscosity of the thermomass gas.

Improvements in ecosystem services from investments in natural capital.

In response to ecosystem degradation from rapid economic development, China began investing heavily in protecting and restoring natural capital starting in 2000. We report on China's first national ecosystem assessment (2000-2010), designed to quantify and help manage change in ecosystem services, including food production, carbon sequestration, soil retention, sandstorm prevention, water retention, flood mitigation, and provision of habitat for biodiversity. Overall, ecosystem services improved from 2000 to 2010, apart from habitat provision. China's national conservation policies contributed significantly to the increases in those ecosystem services.

Recent ecological transitions in China: greening, browning, and influential factors.

Ecological conservation and restoration are necessary to mitigate environmental degradation problems. China has taken great efforts in such actions. To understand the ecological transition during 2000-2010 in China, this study analysed trends in vegetation change using remote sensing and linear regression. Climate and socioeconomic factors were included to screen the driving forces for vegetation change using correlation or comparative analyses. Our results indicated that China experienced both vegetation greening (restoration) and browning (degradation) with great spatial heterogeneity. Socioeconomic factors, such as human populations and economic production, were the most significant factors for vegetation change. Nature reserves have contributed slightly to the deceleration of vegetation browning and the promotion of greening; however, a large-scale conservation approach beyond nature reserves was more effective. The effectiveness of the Three-North Shelter Forest Program lay between the two above approaches. The findings of this study highlighted that vegetation trend detection is a practical approach for large-scale ecological transition assessments, which can inform decision-making that promotes vegetation greening via proper socioeconomic development and ecosystem management.

[Assessment of the impacts of soil erosion on water environment based on the integration of soil erosion process and landscape pattern].

The integration of the effects of landscape pattern to the assessment of the impacts of soil erosion on eco-environmental is of practical significance in methodological prospect, being able to provide an approach for identifying water body's sediment source area, assessing the potential risks of sediment export of on-site soil erosion to the target water body, and evaluating the capacity of regional landscape pattern in preventing soil loss. In this paper, the RUSLE model was applied to simulate the on-site soil erosion rate. With the consideration of the soil retention potential of vegetation cover and topography, a quantitative assessment was conducted on the impacts of soil erosion in the water source region of the middle route for South-to-North Water Transfer Project on rivers and reservoirs by delineating landscape pattern at point (or cell) scale and sub-watershed level. At point (or grid cell) scale, the index of soil erosion impact intensity (I) was developed as an indicator of the potential risk of sediment export to the water bodies. At sub-watershed level, the landscape leakiness index (LI) was employed to indicate the sediment retention capacity of a given landscape pattern. The results revealed that integrating the information of landscape pattern and the indices of soil erosion process could spatially effectively reflect the impact intensity of in situ soil erosion on water bodies. The LI was significantly exponentially correlated to the mean sediment retention capacity of landscape and the mean vegetation coverage of watershed, and the sediment yield at sub-watershed scale was significantly correlated to the LI in an exponential regression. It could be concluded that the approach of delineating landscape pattern based on soil erosion process and the integration of the information of landscape pattern with its soil retention potential could provide a new approach for the risk evaluation of soil erosion.