Identification and quantification of the distribution, ecological risk, and sources of heavy metals in soils are essential for regional pollution control and management. In this study, spatial ...analysis (SA), GeogDetector model (GDM), and positive matrix factorization (PMF) model were combined to evaluate the status, ecological risk, and sources of heavy metals in soils from a typical coastal economic development area in Southeastern China. The mean contents of Cd, Pb, Cr, Cu, and Zn in the surface soils (0–20 cm) were 0.45, 41.72, 90.50, 47.86, and 145.33 mg/kg, respectively. In accordance, the mean contents of Cd exceeded the risk screening value for contamination of agricultural soil in China. Our results revealed that industrial and residential soils had higher enrichment of heavy metals than agricultural and fallow soils. Industrial production was the major driving factors influencing the spatial distribution of heavy metals. Soil OM and pH were found to be the most important factors affecting the potential ecological risk of heavy metals, followed by distance from the industrial enterprises and roads. Heavy metals in the study area were mainly originated from industrial emissions/atmospheric deposition, agricultural sources, and followed by natural sources. Therefore, regular monitoring and source control for heavy metals, especially for Cd, along with the integrated soil environmental management in the study area are crucial to ensure soil health and ecosystem security.
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•Integration of SA, GeogDetector, and PMF models to identify the risk and source of heavy metals.•Cd was the most prevalent contaminant in soils among all the studied heavy metals.•Industrial activities are the main driving factors influencing heavy metal spatial variation.•Environmental factors are associated with the potential ecological risk of heavy metals.•Integrated management should be implemented to mitigate heavy metal pollution.
Objective
The objective of the study is to explore the value of the four-section approach in detecting fetal heart defects in the first trimester (11–13
+6
weeks), analyze the reasons for the ...inconsistency between the results of ultrasound examination in the first trimester and subsequent verification, and describe the most common abnormal flow patterns of four sections.
Materials and methods
Between June 2019 and June 2021, a prenatal four-section approach (upper abdominal transverse section, four-chamber section, three vessel–trachea section, and bilateral subclavian artery section) with verification results in early pregnancy was analyzed.
Results
In total, 9,533 fetuses were included. Finally, 176 fetuses with congenital heart disease (CHD), containing 34 types, were identified. The total detection rate of cardiac abnormalities was 1.85%. 102 cases were accurately diagnosed by ultrasonography during early pregnancy. A total of 74 fetuses who had inconsistent results between fetal cardiac ultrasound and verification in early pregnancy were reported, of which the cases of 22 fetuses were inconsistent due to disease evolution and progression and the cases of 52 fetuses were inconsistent due to missed diagnosis and misdiagnosis. The sensitivity, specificity, positive predictive value, and negative predictive value of the four-section approach were 67.05%, 99.96%, 96.58%, and 99.33%, respectively. In this study, a total of 30 abnormal ultrasonic imaging patterns in four sections were summarized.
Conclusion
We confirmed that the four-section approach in early pregnancy has a good diagnostic efficacy for fetal CHD. Intrauterine evolution of the fetal heart, missed diagnosis, and misdiagnosis are the reasons for the inconsistency between the results of early pregnancy ultrasound and subsequent verification. This study also presents the abnormal imaging patterns of four scan sections of CHD in early pregnancy, which are instructive for the rapid identification and diagnosis of CHD in the first trimester.
This study aims to investigate the efficacy of prenatal ultrasonography in diagnosing the anomalous origin of the fetal pulmonary artery (AOFPA).
A total of 26 AOFPA cases were retrospectively ...analyzed from January 2014 to January 2023. The features of the AOFPA were characterized by comparing the prenatal ultrasonic data with the results of anatomical casting after pregnancy termination or postnatal imaging and surgical intervention. Missed diagnoses and misdiagnoses were expounded.
Of the 26 AOFPA cases, there were 13 cases of pulmonary artery sling, 8 cases of anomalous origin of the unilateral pulmonary artery, and five cases of unilateral absence of the pulmonary artery; 17 cases received pathological anatomy and casting after pregnancy termination, and nine cases were confirmed by postnatal imaging and surgery. Nineteen cases were accurately prenatally diagnosed (19/26, 73.1%), and seven cases were missed or misdiagnosed (7/26, 26.9%).
Prenatal ultrasonography has a favorable diagnostic efficacy for anomalous origin of the fetal pulmonary artery. The absence of either the left or right pulmonary artery from the image of pulmonary artery bifurcation may indicate origin abnormalities of the pulmonary artery in fetuses, which signifies the necessity to detect the abnormal origin of the pulmonary artery on the affected side and other potential intracardiac malformation complications.
To explore the diagnostic clues and abnormality spectrum of heterotaxy syndrome by prenatal ultrasonography and postnatal verification.
The prenatal ultrasonic data of 88 heterotaxy syndrome fetuses ...were analyzed retrospectively as left isomerism (LI) and right isomerism (RI). Prenatal ultrasound compared with the anatomical casting of the fetal body after labor induction, and the confirmatory postnatal diagnosis after delivery.
Fetal LI showed typical malformations of gastric vesicles on different sides from the heart, absence of hepatic segment of the inferior vena cava (IVC), abdominal aorta (AO) parallel with the azygos vein (AV), bilateral left bronchus, bilateral left atrial appendages, and polysplenia; intracardiac malformations of AV septal defects (AVSD), single atrium (SA), left ventricular outflow tract obstruction (LVOTO), and double-outlet right ventricle (DORV); and cardiac conduction abnormalities of sinus bradycardia and AV blockage. Fetal RI reported typical malformations of gastric vesicles on different sides from the heart, juxtaposition of the IVC with AO, anomalous pulmonary venous connection (APVC), asplenia, and bilateral right atrial appendages; intracardiac malformations of AVSD, SA, single ventricle, pulmonary atresia and stenosis, and DORV. The postnatal verification revealed 3 malformations misdiagnoses and 4 malformations missed diagnoses in LI fetuses and 10 misdiagnoses and 8 missed diagnoses in RI fetuses.
The proposed five-step prenatal ultrasonography has an important diagnostic value for the identification and classification of heterotaxy syndrome. The different sides of gastric vesicles and cardiac apex are important diagnostic clues for heterotaxy syndrome, featuring disconnected or hypoplastic IVC, typical complex cardiac malformation, and atrioventricular block in fetal LI, and shown APVC, juxtaposition of IVC and AO, and intracardiac malformations such as AVSD, DORV, and LVOTO in fetal RI.
Objective To examine the effect of exosomes derived from lung adenocarcinoma cells on macrophage polarization and the change of cytobiological behaviors in lung cancer cells induced by activated ...macrophages. Methods Exosomes derived from lung adenocarcinoma cells were extracted by exosomes extraction kit. The expression of exosomal markers including CD9 and CD63 was detected by Western blot analysis. After THP-1 cells were treated with 100 ng/mL phorbol ester (PMA) for 48 hours, the macrophage marker of CD68 was detected by real-time quantitative PCR (RT-qPCR). Following 24-hour treatment of macrophages with the exosomes (200 μg/mL), the mRNA levels of transforming growth factor β (TGF-β), tumor necrosis factor α (TNF-α), inducible nitric oxide synthase (iNOS) and CD163 were detected by RT-qPCR, and the protein levels of IL-6, IL-8 and IL-10 were measured by IMMULITE 1000. The macrophages after exosome treatment were co-cultured with A549 or H1299 cells. The invasion of lung adenocarcinoma cells was tested by
The influence of the dopant Bentonite, on the ionic conductivity of the PVA-KOH-H2O alkaline solid polymer electrolyte (ASPE) is studied. The results show that the addition of Bentonite has both ...positive and negative effects on the ionic conductivity of ASPE. At lower KOH and H2O contents, the addition of Bentonite can break the continuous ion conducting phase of the ASPE, and therefore decrease the ASPE conductivity. However, the addition of Bentonite can also increase the KOH content in PVA matrix. This greatly increases the conductivity of the ASPE especially at higher water content. A highest ionic conductivity of 0.11Scm-1 is reached at room temperature. A maximum ionic conductivity value is observed at relative lower water content for different amount of Bentonite-doped ASPE. The temperature dependence of the ionic conductivity is of the Arrhenius type. The ion transfer activation energy Ea, in the order of 4-6kJmol-1, heavily depends on the Bentonite content. XRD and SEM tests show that PVA in the Bentonite-doped ASPE is of amorphous structure, and there are lots of interspaces in the composite ASPE inner structure. The composite electrolyte has good electrochemical stability window and good charged-discharge property in secondary Zn-Ni cells at low charge-discharge rate.
In the environmental ecosystem, there are no absolutely isolated risks. Each risk might be influenced by multiple environmental factors and the factors’ interaction within the specific system. Hence, ...health risk assessments of heavy metal contamination must consider multiple environmental media and their transfer processes from one medium to another. Integrated assessments provide a new perspective for evaluating many factors, such as the potential ecological risks of soils, sediments, plants, and the transportation of heavy metals in these media, which influences the health risks. In this study, the main influencing factors for human health risk from heavy metals along the Yangtze River in Nanjing, Southeast China, were explored. The contents of five heavy metals were measured in sediment-soil-plant, including cadmium (Cd), lead (Pb), copper (Cu), zinc (Zn), and chromium (Cr). The Cd displayed the highest potential ecological risk in soils and sediments, as it possessed high bioaccessibility (BA; 0.17 ± 0.211) and bioaccumulation factor (BCF; 0.35 ± 0.33). The 5.97% of the target hazard quotient (THQ) of Cd were higher than 1, indicating a potential health risk in plant consumption. Based on the geodetector model, determinant power (DP) valves for factors influencing health risk strongly suggest that plant types (0.479) has a highest effect, followed by soil organic matter (SOM; 0.292), and the BA of heavy metals (0.107). The results also indicate that pollution from the upper reaches of the river, and agricultural activities, had a greater impact on health risk than did industrial activities in the study area. Thus, regular monitoring and source control for Cd, along with integrated agricultural management practices should be implemented to control and reduce heavy metal inputs and improve the safety of cultivated plants.
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•The influence factors analysis for health risk should be based on multi-mediums.•Cadmium had the highest health risk for residents and potential ecological risks.•The distribution of plant species best reflects the distribution of health risks.•The influence of historical anthropogenic was greater than recent human activities.•Geodetector can accurately analyze the determination power of influence factors.
By Gouy–Chapman–Stern–Grahame (CGSG) model, the electric double layer at ion exchange membrane/solution interface consists of two parts: the Stern layer and the diffusion layer. The ions in Stern ...layer are compacted and considered to be immobile. The relation of diffusion layer mean conductivity
K with outer Stern layer potential
φ
0, the boundary potential
φ
δ
and the electrolyte concentration
C
0 is educed for symmetric electrolyte system. The results show that
K is higher than that of the bulk solution and is greatly influenced by
φ
0,
φ
δ
and
C
0.
The examination of PE01 cation exchange membrane/solution interface resistance
R
e measured by ac impedance technique, shows that
R
e value decreases quickly as the KCl electrolyte concentration rises. The effect of electrolyte concentration on the resistance of EDL can be explained by the electrical interactions between ions and charged groups of the membrane. Since the membrane/solution interface resistance is much higher than that of bulk solution, therefore, a further analysis based on the theory developed in this study proves that the ion transfer resistance
R
e of membrane–solution interface predominantly occurs at Stern layer as a result of static electrical interaction.
The AC fault ride-through and support capability of line commutated converter based high voltage direct current (LCC-HVDC) have significant influence on the safe operation of power system. The ...ability of phase locked loop (PLL) to synchronize with the voltage phase under AC faults would affect the recovery performance of LCC-HVDC systems. This paper analyzes the influence of the conventional PLL on the subsequent commutation failure (SCF) of LCC-HVDC systems and points out that the conventional PLL has some problems such as slow dynamic response, significant frequency fluctuation, and coupling of phase and frequency detection under fault conditions. A novel PLL is proposed to address the problems. Cascade delayed signal cancellation operators are combined with a mathematical filter, forming a hybrid pre-filter to extract fundamental positive sequence voltage for the PLL. To reduce the fluctuation of PLL's frequency during AC faults, the estimated frequency is fixed when the fault is detected by a fault detector. As a consequence, the decoupling between phase detection and frequency detection is realized, and the proposed PLL's dynamic response performance is enhanced. Simulation results show that the proposed PLL can provide accurate phase reference for the DC control system and reduce the probability of SCFs of LCC-HVDC system.
