Heavy metals in the surface soils from lands of six different use types in one of the world's most densely populated regions, which is also a major global manufacturing base, were analyzed to assess the impact of urbanization and industrialization on soil pollution. A total of 227 surface soil samples were collected and analyzed for major heavy metals (As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn) by using microwave-assisted acid digestion and inductively coupled plasma-mass spectrometry (ICP-MS). Multivariate analysis combined with enrichment factors showed that surface soils from the region (>7.2×10 4 km 2 ) had mean Cd, Cu, Zn, and As concentrations that were over two times higher than the background values, with Cd, Cu, and Zn clearly contributed by anthropogenic sources. Soil pollution by Pb was more widespread than the other heavy metals, which was contributed mostly by anthropogenic sources. The results also indicate that Mn, Co, Fe, Cr, and Ni in the surface soils were primarily derived from lithogenic sources, while Hg and As contents in the surface soils were controlled by both natural and anthropogenic sources. The pollution level and potential ecological risk of the surface soils both decreased in the order of: urban areas>waste disposal/treatment sites∼industrial areas>agri-cultural lands∼forest lands>water source protection areas. These results indicate the significant need for the development of pollution prevention and reduction strategies to reduce heavy metal pollution for regions undergoing fast industrialization and urbanization.
The composite flooding
system composed of a surfactant and nanoparticles
has shown great application potential in enhancing oil recovery. However,
at present, these research studies are mainly focused on anionic surfactants.
Relatively speaking, alkanolamide (CDEA), a nonionic surfactant, has
the characteristics of a small adsorption amount on the rock surface,
no cloud point, good temperature resistance, and good salt resistance.
However, to the best of our best knowledge, there is no research report
on the composite flooding system composed of CDEA and nanoparticles.
Therefore, the surfactant/nanoparticle (S/NP) flooding system based
on CDEA and nano-SiO
2
was studied in this paper. The S/NP
flooding system (0.1% CDEA + 0.05% SiO
2
) was constructed
based on the performance in reducing the oil–water interfacial
tension (IFT) and the stability of the composite system. The IFT between
the S/NP flooding system and the crude oil can reach ultra-low values
(3 × 10
–3
mN/m), and there is no obvious sedimentation
within 72 h. The sandpack flood tests show that the oil recovery rate
is increased by 16.8% compared with water flooding and finally reaches
58.2%. Based on micromodel flooding tests, the mechanisms of the S/NP
flooding system are studied as follows: the synergistic effect of
nanoparticles and surfactants can re-enforce its oil–water
interface performance and improve the oil displacement efficiency
and the Jamin effect of emulsified oil droplets, combined with the
thickening property and retention plugging of nanoparticles, improves
the sweep efficiency. As the surfactant and nanoparticle used in this
study are commercially available industrial products, the research
results have important guiding significance for promoting the industrial
application of surfactant/nanoparticle composite flooding technology.
Background
Proprotein convertase subtilisin/kexin type (PCSK9) inhibitor is a new drug class approved for treating dyslipidemias. Herein, we aimed to investigate the safety profiles of PCSK9 inhibitors (alirocumab and evolocumab) using the Food and Drug Administration Adverse Event Reporting System (FAERS).
Methods
We included adverse event (AE) reports regarding alirocumab and evolocumab submitted to the FAERs between 2015Q3 to 2021Q1. Disproportionality analyses, including reporting odds ratio (ROR), were performed to detect risk signals from the FAERs data to identify potential drug‐AE associations. A signal was considered when the lower limit of the 95% confidence interval of ROR exceeded 1 and ≥3 AEs were reported. The definition relied on system organ class and preferred terms established by the Medical Dictionary for Regulatory Activities.
Results
The FAERS database documented 31 475 reports regarding PCSK9 inhibitors (alirocumab and evolocumab) from July 1, 2015, to March 31, 2021. Although some differences were detected, alirocumab and evolocumab shared considerably similar safety profiles. The most significant RORs and most common reports were injection‐site reactions (eg, injection‐site pain, bruising, haemorrhage, erythema), muscle‐related AEs (eg, myalgia, back pain, arthralgia, muscle spasms), influenza‐like illness, pain and headache.
Conclusion
Data mining of the FAERs is useful for examining PCSK9 inhibitor‐induced AEs. Herein, our findings were largely consistent with clinical experience and could help clinicians improve the safety of PCSK9 inhibitors in clinical practice.
Heavy metal pollution is an increasing environmental problem in Chinese regions undergoing rapid economic and industrial development, such as the Pearl River Delta (PRD), southern China. We determined heavy metal concentrations in surface soils from the PRD. The soils were polluted with heavy metals, as defined by the Chinese soil quality standard grade II criteria. The degree of pollution decreased in the order Cd > Cu > Ni > Zn > As > Cr > Hg > Pb. The degree of heavy metal pollution by land use decreased in the order waste treatment plants (WP) > urban land (UL) > manufacturing industries (MI) > agricultural land (AL) > woodland (WL) > water sources (WS). Pollution with some of the metals, including Cd, Cu, Ni, and Zn, was attributed to the recent rapid development of the electronics and electroplating industries. Cd, Hg, and Pb (especially Cd) pose high potential ecological risks in all of the zones studied. The soils posing significantly high and high potential ecological risks from Cd covered 73.3 % of UL, 50 % of MI and WP land, and 48.5 % of AL. The potential ecological risks from heavy metals by land use decreased in the order UL > MI > AL > WP > WL > WS. The control of Cd, Hg, and Pb should be prioritized in the PRD, and emissions in wastewater, residue, and gas discharges from the electronics and electroplating industry should be decreased urgently. The use of chemical fertilizers and pesticides should also be decreased.
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