Thin-Film Composite Membrane Compaction: Exploring the Interplay among Support Compressive Modulus, Structural Characteristics, and Overall Transport Efficiency.

Water scarcity has driven the demand for water production from unconventional sources and the reuse of industrial wastewater. Pressure-driven membranes, notably thin-film composite (TFC) membranes, stand as energy-efficient alternatives to the water scarcity challenge and various wastewater treatments. While pressure drives solvent movement, it concurrently triggers membrane compaction and flux deterioration. This necessitates a profound comprehension of the intricate interplay among compressive modulus, structural properties, and transport efficacy amid the compaction process. In this study, we present an all-encompassing compaction model for TFC membranes, applying authentic structural and mechanical variables, achieved by coupling viscoelasticity with Monte Carlo flux calculations based on the resistance-in-series model. Through validation against experimental data for multiple commercial membranes, we evaluated the influence of diverse physical parameters. We find that support polymers with a higher compressive modulus (lower compliance), supports with higher densities of "finger-like" pores, and "sponge-like" pores with optimum void fractions will be preferred to mitigate compaction. More importantly, we uncover a trade-off correlation between steady-state permeability and the modulus for identical support polymers displaying varying porosities. This model holds the potential as a valuable guide in shaping the design and optimization for further TFC applications and extending its utility to biological scaffolds and hydrogels with thin-film coatings in tissue engineering.

Prognostic Value of Fibrinogen-to-Albumin Ratio in Coronary Three-Vessel Disease.

Objective: To investigate the prognostic value of fibrinogen-to-albumin ratio (FAR) in the adverse outcomes of patients with coronary three-vessel disease (TVD). Methods: A total of 4061 patients with TVD between 2013 and 2018 were analyzed in this retrospective cohort study. The best cut­off value of the FAR determined by receiver operating characteristic (ROC) curve analysis was 0.084. 2782 (68.5%) patients were in the low FAR group (FAR < 0.084) and 1279 (31.5%) patients were in the high FAR group (FAR ≥ 0.084), respectively. Three multivariate Cox proportional hazards models were applied to determine the associations of FAR with clinical outcomes. The concordance index (C-index), net reclassification index (NRI), and integrated discrimination improvement (IDI) were used to assess the incremental predictive value of the FAR and baseline models with respect to the additive effects of the established traditional risk factors on the discrimination of clinical outcomes. The primary endpoint was all-cause mortality. The secondary endpoint was major adverse cardiac and cerebrovascular events (MACCEs). Results: The median follow-up duration was 2.4 years (range 1.1-4.1 years). Multivariate Cox regression analyses showed that the incidence of all-cause mortality (4.7% vs 2.2%, adjusted hazard ratio [HR] 1.68, 95% confidence interval [CI] 1.12-2.52, p=0.011) and MACCE (34.6% vs 27.3%, HR 1.28, 95% CI 1.13-1.46, p<0.001) were significantly higher in the high FAR group compared to the low FAR group. The C-index was 0.72 (p < 0.001), the value of NRI was 0.3778 (p < 0.001), and the value of IDI was 0.0098 (p < 0.001) for those with FAR. After FAR was added to the traditional model, the discrimination and risk reclassification ability can be significantly improved for all-cause mortality. The similar results were found for MACCE. Conclusion: Higher level of FAR was associated with all-cause mortality and MACCE among patients with TVD. FAR could help to improve the prognostic performance of the traditional risk factors for TVD patients.

Benefit of Catheter Ablation for Atrial Fibrillation in Heart Failure Patients with Different Etiologies.

(1) Background: A plethora of studies have elucidated the safety and efficacy of catheter ablation (CA) for patients afflicted with atrial fibrillation (AF) and concomitant reduction in left ventricular ejection fraction (LVEF). Nevertheless, the literature on the benefits of CA in the specific etiological context of heart failure (HF) remains limited. This study delineates a comparative assessment of outcomes for patients with AF and reduced LVEF across the primary etiologies. (2) Methods: Our inquiry encompassed 216 patients diagnosed with congestive heart failure and an LVEF of less than 50 percent who were referred to our institution for circumferential pulmonary vein isolation (CPVI) between the years 2016 and 2020. The selection criteria included a detailed medical history while excluding those suffering from valvular disease, congenital heart disease, and hypertrophic cardiomyopathy. In an effort to scrutinize varying etiologies, patients were stratified into three categories: dilated cardiomyopathy (DCM, n = 56, 30.6%), ischemic cardiomyopathy (ICM, n = 68, 37.2%), and tachycardia-induced cardiomyopathy (TIC, n = 59, 32.2%). (3) Results: Following an average (±SD) duration of 36 ± 3 months, the prevalence of sinus rhythm was 52.1% in the DCM group, 50.0% in the ICM group, and 68.14% in the TIC group (p = 0.014). This study revealed a significant disparity between the DCM and TIC groups (p = 0.021) and the ICM and TIC groups (p = 0.007), yet no significant distinction was discerned between the TIC and ICM groups (p = 0.769). Importantly, there were no significant variations in the application of antiarrhythmic drugs or recurrence of procedures among the three groups. The mortality rates were 14.29% for the DCM group and 14.71% for the ICM group, which were higher than the 3.39% observed in the TIC group (DCM vs. TIC p = 0.035 (HR = 4.50 (95%CI 1.38-14.67)), ICM vs. TIC p = 0.021 (HR = 5.00 (95%CI 1.61-15.50))). A noteworthy enhancement in heart function was evidenced in the TIC group in comparison to the DCM and ICM groups, including a higher LVEF (p < 0.001), diminution of LV end-diastolic diameter (p < 0.001), and an enhanced New York Heart Association classification (p = 0.005). Hospitalization rates for heart failure were discernibly lower in TIC patients (0.98 (0,2) times) relative to those with DCM (1.74 (0,3) times, p < 0.01) and TIC (1.78 (0,4) times, p < 0.001). Patients with paroxysmal atrial fibrillation and brief episodes were found to achieve superior clinical outcomes through a catheter ablation strategy. (4) Conclusion: Patients diagnosed with TIC demonstrated a more pronounced benefit from catheter ablation compared to those with DCM and ICM. This encompassed an augmented improvement in cardiac function, an enhanced maintenance of sinus rhythm, and a reduced mortality rate.

Core fucosylation regulates alveolar epithelial cells senescence through activating of transforming growth factor-ß pathway in pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF), a fatal disorder associated with aging, has a terrible prognosis. However, the potential causes of IPF remain a riddle. In this study, we designed to explore whether the modification of the core fucosylation (CF) can ameliorate pulmonary fibrosis by targeting alveolar epithelial cells (AECs) senescence. First, we verified that cellular senescence occurs in the bleomycin-induced lung fibrosis mice models and CF modifications accompanying senescent AECs in pulmonary fibrosis. Next, both gain- and loss- of function research on CF were performed to elucidate its role in promoting AECs senescence and triggering pulmonary fibrosis in vitro. Notably, using alveolar epithelial cell-specific FUT8 conditional knockout mouse models, however, inhibition of cellular senescence by deleting the FUT8 gene could attenuate pulmonary fibrosis in vivo. Finally, blocking the CF modification of transforming growth factor -ß type I receptor (TGF-ßR I) could reduce the activation of downstream transforming growth factor -ß (TGF-ß) pathways in AECs senescence both in vivo and in vitro. This study reveals that CF is a crucial interventional target for the treatment of pulmonary fibrosis. Blocking CF modification contributes importantly to inhibiting AECs senescence resulting in pulmonary fibrosis lessen.

Photochemical Benzylation of White Phosphorus.

Organophosphorus compounds (OPCs) have wide application in organic synthesis, material sciences, and drug discovery. Generally, the vast majority of phosphorus atoms in OPCs are derived from white phosphorus (P4). However, the large-scale preparation of OPCs mainly proceeds through the multistep and environmentally toxic chlorine route from P4. Herein, we report the direct benzylation of P4 promoted by visible light. The cheap and readily available benzyl bromide was used as a benzylation reagent, and tetrabenzylphosphonium bromide was directly synthesized from P4. In addition, the metallaphotoredox catalysis strategy was applied to functionalize P4 for the first time, which significantly improved the application range of the substituted benzyl bromide.

The feasibility and safety of his-purkinje conduction system pacing in patients with heart failure with severely reduced ejection fraction.

Objective: The purpose of this study was to evaluate the feasibility and outcomes of conduction system pacing (CSP) in patients with heart failure (HF) who had a severely reduced left ventricular ejection fraction (LVEF) of less than 30% (HFsrEF). Methods: Between January 2018 and December 2020, all consecutive HF patients with LVEF < 30% who underwent CSP at our center were evaluated. Clinical outcomes and echocardiographic data [LVEF and left ventricular end-systolic volume (LVESV)], and complications were all recorded. In addition, clinical and echocardiographic (≥5% improvement in LVEF or ≥15% decrease in LVESV) responses were assessed. The patients were classified into a complete left bundle branch block (CLBBB) morphology group and a non-CLBBB morphology group according to the baseline QRS configuration. Results: Seventy patients (66 ± 8.84 years; 55.7% male) with a mean LVEF of 23.2 ± 3.23%, LVEDd of 67.33 ± 7.47 mm and LVESV of 212.08 ± 39.74 ml were included. QRS configuration at baseline was CLBBB in 67.1% (47/70) of patients and non-CLBBB in 32.9%. At implantation, the CSP threshold was 0.6 ± 0.3 V @ 0.4 ms and remained stable during a mean follow-up of 23.43 ± 11.44 months. CSP resulted in significant LVEF improvement from 23.2 ± 3.23% to 34.93 ± 10.34% (P < 0.001) and significant QRS narrowing from 154.99 ± 34.42 to 130.81 ± 25.18 ms (P < 0.001). Clinical and echocardiographic responses were observed in 91.4% (64/70) and 77.1% (54/70) of patients. Super-response to CSP (≥15% improvement in LVEF or ≥30% decrease in LVESV) was observed in 52.9% (37/70) of patients. One patient died due to acute HF and following severe metabolic disorders. Baseline BNP (odds ratio: 0.969; 95% confidence interval: 0.939-0.989; P = 0.045) was associated with echocardiographic response. The proportions of clinical and echocardiographic responses in the CLBBB group were higher than those in the non-CLBBB group but without significant statistical differences. Conclusions: CSP is feasible and safe in patients with HFsrEF. CSP is associated with a significant improvement in clinical and echocardiographic outcomes, even for patients with non-CLBBB widened QRS.

Cesium Amide-Catalyzed Selective Deuteration of Benzylic C-H Bonds with D2 and Application for Tritiation of Pharmaceuticals.

Hydrogen isotope exchange (HIE) represents one of the most attractive labeling methods to synthesize deuterium- and tritium-labeled compounds. Catalytic HIE methods that enable site-selective C-H bond activation and exchange labeling with gaseous isotopes D2 and T2 are of vital importance, in particular for high-specific-activity tritiation of pharmaceuticals. As part of our interest in exploring s-block metals for catalytic transformations, we found CsN(SiMe3 )2 to be an efficient catalyst for selective HIE of benzylic C-H bonds with D2 gas. The reaction proceeds through a kinetic deprotonative equilibrium that establishes an exchange pathway between C-H bonds and D2 gas. By virtue of multiple C-H bonds activation and high activity (isotope enrichment up to 99 %), the simple cesium amide catalyst provided a very powerful and practically convenient labeling protocol for synthesis of highly deuterated compounds and high-specific-activity tritiation of pharmaceuticals.

Dual tolerance of ageratum (Ageratum conyzoides L.) to combined pollution of acid and cadmium: Field survey and pot experiment.

A field survey and pot experiment were carried out to screen tolerant plants growing in cadmium (Cd)-polluted mining areas which were co-polluted with acid in soil, and the related physiological and biochemical mechanisms were also analyzed. Thirty-seven species of wild plants and their corresponding soil were collected from a farmland around the mining areas. Ageratum (Ageratum conyzoides L.) with strong Cd-accumulative ability was selected, and its tolerance experiment for acid and Cd with different levels were carried out separately or orthogonally, respectively. Furthermore, the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), and the contents of malondialdehyde (MDA), photosynthetic pigments, soluble sugar and proline in its leaves were determined. The results showed that the Cd accumulation in ageratum and sticktight (Bidens pilosa L.) was relatively high, but the latter has been well documented, so we focused on ageratum in the present work. In pot experiment, ageratum grew normally at 100 mg kg-1 Cd in soil, and the Cd concentrations in its roots, stems and leaves were 75.37 ± 7.37, 31.01 ± 3.76 and 53.92 ± 10.05 mg kg-1, respectively. In the case of acid tolerance experiment, all plant individuals of ageratum grew normally when soil pH was over 3.5. In the orthogonal experiment, the Cd accumulation in this plant increased with the decrease of soil pH under the same Cd treatment. Under strong acid conditions, the activity of SOD in leaves of ageratum was increased significantly. When the Cd concentration was 10 mg kg-1 and the soil pH was 5.5 or 3.5, the activities of POD and CAT were significantly increased. In addition, based on stepwise regression analysis, the leaf Cd concentration was significantly positive correlated with the activities of SOD and POD in leaves of ageratum. Therefore, ageratum not only had a strong tolerance for Cd and acid pollution in soil, but also had a strong ability to accumulate Cd. As a common plant in the mining area, it has a great potential for the phytoremediation of Cd and acid co-contaminated soil.

A comprehensive assessment of heavy metal(loid) contamination in leafy vegetables grown in two mining areas in Yunnan, China-a focus on bioaccumulation of cadmium in Malabar spinach.

Contamination of leafy vegetables grown in heavy metal(loid)-polluted mining areas pose serious health risks. This study aimed to explore the heavy metal(loid) contamination of leafy vegetables near two mining areas, by collecting samples from 14 different leafy vegetable species in Yunnan Province, China. The lead (Pb), cadmium (Cd), arsenic (As), and copper (Cu) contents of the samples were determined, and risks to human health were calculated using the hazard quotient and hazard index (HI). Moreover, Malabar spinach was identified as a leafy vegetable that exhibits low accumulation of heavy metal(loid)s. The accumulation capacity of different Malabar spinach varieties was verified, and a Cd soil safety threshold was determined using a pot experiment. Overall, Pb and Cd were the main soil and vegetable contaminants found in both study sites. The HI values for all leafy vegetables, apart from Malabar spinach, were greater than 1, indicating the presence of risks to human health; moreover, the health risks were greater for children than adults. The Malabar spinach pot experiment results showed that only some Cd forms exceeded China's maximum permissible standards. Furthermore, Malabar spinach varieties A (instant Malabar spinach), C (extra-large leaf green vine Malabar spinach), and F (large leaf Malabar spinach) displayed the lowest Cd accumulation. We calculated Cd total and bioavailable soil safety thresholds of 4.75 and 0.77 mg kg-1, respectively. However, further research is required to validate soil heavy metal safety thresholds for different vegetables. Ultimately, the heavy metal(loid) contamination of leafy vegetables described here was more serious than anticipated. Finally, the results of this study can inform residents living near these mining areas of a low-risk leafy vegetable, which will reduce the harm caused by heavy metal(loid) contamination in the area.

Cardiomyopathy induced by premature ventricular contractions with ventricular escape beats in the compensatory pause: A case report and brief review of the literature.

RATIONALE: We reported a case with cardiomyopathy induced by frequent premature ventricular contractions (PVCs) and followed ventricular escape beats (VEBs). PVCs with VEBs in the compensatory pause which induced cardiomyopathy is rarely reported. Also, the case exhibited many characteristics of PVCs which were more likely to induce cardiomyopathy, like the location of origin, the longer coupling interval, and the QRS wave companied with the P wave. PATIENT CONCERNS: A 53-year-old man with left ventricular (LV) dysfunction presented with palpation, chest distress, and dyspnea for 3 years. Holter revealed a high burden of ventricular rhythm of PVCs and another wide QRS patterns (96,562 total beats with 87,330 wide QRS beats in 24 hours). The LV ejection fraction decreased to 34% and the left ventricle, right and left atria all dilated. DIAGNOSIS: He was diagnosed with PVC-induced cardiomyopathy. INTERVENTIONS: The patient experienced intracardiac electrophysiological examination which revealed frequent PVCs followed by VEBs in the compensatory pause. Activation mapping of the PVCS and ablation were performed. OUTCOMES: PVCs and VEBs disappeared after ablation. The LV ejection fraction increased to 46% at 2 days after the procedure. The diameters of the right and left atria were also significantly reduced. LESSONS: VEBs may occur during the compensatory pause of PVCs. PVCs with VEBs can lead to a high burden of ventricular rhythm and LV dysfunction. Ablation of the PVCs can also eliminate VEBs and improve the LV function.

Optimal Catheter Ablation Strategy for Patients with Persistent Atrial Fibrillation and Heart Failure: A Retrospective Study.

The optimal catheter ablation (CA) strategy for patients with persistent atrial fibrillation (PeAF) and heart failure (HF) remains uncertain. Between 2016 and 2020, 118 consecutive patients with PeAF and HF who underwent the CA procedure in two centers were retrospectively evaluated and divided into the pulmonary vein isolation (PVI)-only and PVI + additional ablation groups. Transthoracic echocardiography (TTE) was performed at baseline, one month, and 12 months after the CA procedure. The HF symptoms and left ventricular ejection fraction (LVEF) improvements were analyzed. Fifty-six patients underwent PVI only, and 62 patients received PVI with additional ablation. Compared with the baseline, a significant improvement in the LVEF and left atrial diameter postablation was observed in all patients. No significant HF improvement was detected in the PVI + additional ablation group than in the PVI-only group (74.2% vs. 71.4%, P = 0.736), but the procedure and ablation time were significantly longer (137.4 ± 7.5 vs. 123.1 ± 11.5 min, P = 0.001). There was no significant difference in the change in TTE parameters and the number of rehospitalizations. For patients with PeAF and HF, CA appears to improve left ventricular function. Additional ablation does not improve outcomes and has a significantly longer procedure time. Trial registration number is as follows: ChiCTR2100053745 (Chinese Clinical Trial Registry; https://www.chictr.org.cn/index.aspx).

Impact of baseline impedance of pulmonary vein antrum on success of catheter ablation for paroxysmal atrial fibrillation guided by ablation index.

OBJECTIVE: Ablation index (AI) is an effective ablation quality marker. Impedance is also an important factor for lesion formation. The present study evaluated the influence of the baseline impedance in the effect of ablation for atrial fibrillation (AF) guided by AI. METHODS: This was a retrospective study. 101 patients with paroxysmal AF (PAF) were enrolled. All patients underwent radiofrequency ablation guided by the same AI strategy. The ablation strategy was pulmonary vein (PV) isolation with non-PV triggers ablation. The baseline impedance of the ablation points was recorded. The patients were followed up every 3 months or so. RESULTS: During a median follow-up of 12 (4-14) months, freedom from AF/atrial tachycardia recurrence were 82.2%. No difference existed in baseline characteristics between the success group and the recurrence group. The average baseline impedance was 124.3 ± 9.7 Ω. The baseline impedance of the ablation points in success group was lower compared to the recurrence group (122.9 ± 9.4 vs. 130.5 ± 8.8 Ω, P < 0.01). The ratio of impedance drop in the success group was higher than the recurrence group ([8.8 ± 1.4]% vs. [8.1 ± 1.2]%, P = 0.03). Multivariate analysis revealed that baseline impedance, PAF duration and AI were the independent predictors of AF recurrence. The cumulative free of recurrence rate of low-impedance group (≤ 124 Ω, n = 54) was higher than that of high-impedance group. CONCLUSION: Baseline impedance correlates with clinical outcome of radiofrequency ablation for PAF guided by AI. Higher impedance in the same AI strategy may result in an ineffective lesion which probably causes recurrence.

High-power, short-duration ablation in the coronary sinus: clinical cases and preliminary observations on swine hearts.

PURPOSE: Coronary sinus-related arrhythmias are common; however, it is difficult to perform radiofrequency (RF) ablation at these sites efficiently and safely. High-power, short-duration ablation (HPSD) is a proven alternative strategy for pulmonary vein isolation (PVI); whether it can be applied to ablation of the coronary sinus is unknown. The purpose of this preliminary study was to evaluate the feasibility and safety of HPSD ablation in the coronary sinus. METHODS: Firstly, we demonstrated 4 clinical cases of 3 types of arrhythmias who had unsuccessful ablation with standard power initially, but received successful ablations with HPSD. Secondly, RF ablation was performed in the coronary sinus ostium (CSO) and middle cardiac vein (MCV) of 4 in vitro swine hearts. Two protocols were compared: HPSD (45 W/5 S×5 rounds) and a conventional strategy that used low-power, long-duration ablation (LPLD: 25 W/10 S ×5 rounds). The total duration of HPSD protocol was 25 s, and which of LPLD was 50 s. RESULTS: A total of 28 lesions were created. HPSD can produce longer, wider, deeper, and larger lesions than LPLD. This difference was more pronounced when the ablation was in the MCV. One instance of steam pop occurred during LPLD in the MCV. CONCLUSIONS: HPSD is an effective alternative strategy for ablation in coronary sinus according to clinical applications and preliminary animal study. However, the safety needs to be further evaluated based on more animal and clinical studies.

Protein tyrosine phosphatase non-receptor type 12 (PTPN12), negatively regulated by miR-106a-5p, suppresses the progression of hepatocellular carcinoma.

Protein tyrosine phosphatase non-receptor type 12 (PTPN12) is abnormally expressed in many human cancers. However, its role in hepatocellular carcinoma (HCC) is indeterminate. In this study, immunohistochemistry and Western blot were adopted to detect PTPN12 protein expression in HCC tissues and cell lines. MiR-106a-5p and PTPN12 mRNA expressions were determined by quantitative real-time polymerase chain reaction (qRT-PCR). siRNA was used to knockdown PTPN12 expression in HCC cells, and the multiplication, migration, and invasion of HCC cells were determined by cell counting kit 8 (CCK-8) and Transwell assays. The interaction between PTPN12 and miR-106a-5p was verified by dual-luciferase reporter gene assay and RNA immunoprecipitation (RIP) assay. In the present study, we demonstrated that PTPN12 expression in HCC tissues and cells was significantly decreased, which was associated with the tumor size, TNM stage, and lymph node metastasis of HCC patients. Functionally, knocking down PTPN12 significantly promoted the multiplication, migration, invasion, and epithelial-mesenchymal transition (EMT) of HCC cells. PTPN12 was identified as the direct target of miR-106a-5p, and its expression was negatively modulated by miR-106a-5p. Besides, PTPN12 counteracted the promoting effects of miR-106a-5p on the viability, migration, invasion, and EMT of HCC cells. In conclusion, this study substantiates that PTPN12 inhibits the growth, migration, invasion, and EMT of HCC cells, and miR-106a-5p contributes to its dysregulation in HCC.

Variations of arsenic forms and the role of arsenate reductase in three hydrophytes exposed to different arsenic species.

In order to understand the mechanisms of arsenic (As) accumulation and detoxification in aquatic plants exposed to different As species, a hydroponic experiment was conducted and the three aquatic plants (Hydrilla verticillata, Pistia stratiotes and Eichhornia crassipes) were exposed to different concentrations of As(III), As(V) and dimethylarsinate (DMA) for 10 days. The biomass, the surface As adsorption and total As adsorption of three plants were determined. Furthermore, As speciation in the culture solution and plant body, as well as the arsenate reductase (AR) activities of roots and shoots, were also analyzed. The results showed that the surface As adsorption of plants was far less than total As absorption. Compared to As(V), the plants showed a lower DMA accumulation. P. stratiotes showed the highest accumulation of inorganic arsenic but E. crassipes showed the lowest at the same As treatment. E. crassipes showed a strong ability to accumulate DMA. Results from As speciation analysis in culture solution showed that As(III) was transformed to As(V) in all As(III) treatments, and the oxidation rates followed as the sequence of H. verticillata>P. stratiotes>E. crassipes>no plant. As(III) was the predominant species in both roots (39.4-88.3%) and shoots (39-86%) of As(III)-exposed plants. As(V) and As(III) were the predominant species in roots (37-94%) and shoots (31.1-85.6%) in As(V)-exposed plants, respectively. DMA was the predominant species in both roots (23.46-100%) and shoots (72.6-100%) in DMA-exposed plants. The As(III) contents and AR activities in the roots of P. stratiotes and in the shoots of H. verticillata were significantly increased when exposed to 1 mg·L-1 or 3 mg·L-1 As(V). Therefore, As accumulation mainly occurred via biological uptake rather than physicochemical adsorption, and AR played an important role in As detoxification in aquatic plants. In the case of As(V)-exposed plants, their As tolerance was attributed to the increase of AR activities.

Screening maize (Zea mays L.) varieties with low accumulation of cadmium, arsenic, and lead in edible parts but high accumulation in other parts: a field plot experiment.

To find maize varieties with both safe production and soil remediation, 11 maize varieties were planted in field soil which was combinedly polluted by cadmium (Cd), arsenic (As), and lead (Pb). The plant growth, accumulation, phytochemical forms, and translocation of Cd, As, and Pb in different tissues were examined. Furthermore, maize varieties with low metal accumulation in their edible parts but high accumulation in other parts were selected as remediation candidates and pollution-safe varieties. The results showed that the growth of varieties Yayu69, Longhuang2502, and Shennongyu10 were the least affected by heavy metals. The concentrations of Cd, As, and Pb in all of the tested maize grains met the national feed hygiene standards, and the grain concentrations of the three metals in Yayu69, Shengnongyu10, and Yunrui62 all met the national food safety standards. According to the extraction efficiency of Cd, As, and Pb and heavy metal concentrations in grains, four types of maize were classified as follows: (1) the first category was suitable for both soil remediation and safe production, including the varieties Yayu69 (Cd, Pb), Jinyi418 (As, Cd), and Shengnongyu10 (Pb); (2) the second category had a high concentration of metals in edible part but did not exceed the limiting value in national feed hygiene standards, and the metal extraction efficiency was also high, including Beiyu1521 (Cd) and Longhuang2502 (Cd, As, Pb); (3) the third category included heavy metal exclusion varieties with low metals accumulation, such as Yayu749 (Cd), Yunrui62 (As, Pb), and Yunrui8 (As); and (4) the fourth type covered risk maize varieties with food safety risks and unsuitable cultivation at sites polluted with toxic metals, including Chuangui1586 (Pb) and Enyu69 (As). The variety Yayu69 (a Cd/Pb low accumulator in grain) contained a low percentage of inorganic (FE) and water-soluble (FW) Cd (4%) and Pb (6%) in roots, respectively, but the percentage of FE and FW Cd and Pb in the variety Beiyu1521 (a Cd/Pb high accumulator in grain) was up to 29% and 13%. Our results provided a new perspective in applying maize varieties with different metal-accumulating ability in their different parts to achieve the remediation of metal-polluted soil and the sustainable development of agricultural production.

Diverse Particle Carriers Prepared by Co-Precipitation and Phase Separation: Formation and Applications.

Nanoparticles with diverse structures and unique properties have attracted increasing attention for their widespread applications. Co-precipitation under rapid mixing is an effective method to obtained biocompatible nanoparticles and diverse particle carriers are achieved by controlled phase separation via interfacial tensions. In this Minireview, we summarize the underlying mechanism of co-precipitation and show that rapid mixing is important to ensure co-precipitation. In the binary polymer system, the particles can form four different morphologies, including occluded particle, core-shell capsule, dimer particle, and heteroaggregate, and we demonstrate that the final morphology could be controlled by surface tensions through surfactant, polymer composition, molecular weight, and temperature. The applications of occluded particles, core-shell capsules and dimer particles prepared by co-precipitation or microfluidics upon the regulation of interfacial tensions are discussed in detail, and show great potential in the areas of functional materials, colloidal surfactants, drug delivery, nanomedicine, bio-imaging, displays, and cargo encapsulation.

Effect of soil washing on heavy metal removal and soil quality: A two-sided coin.

Heavy metal contamination in soil due to human activities is a global environmental problem. To find a washing solution that can significantly decontaminate heavy metals and minimize damage to soil quality, six washing solutions (H3PO4, K2CO3, CH3COOK, KH2PO4, HNO3 and KNO3) were used at different concentrations to treat contaminated soil collected from the field. Furthermore, changes in soil physicochemical properties and heavy metal speciation among prewashed, postwashed and neutralized samples were tested. Additionally, soil enzyme activities and soil microbial diversities in contaminated soil among the prewashed, postwashed and neutralized samples were also measured. Finally, a pot experiment was conducted with Mentha haplocalyx to test the efficiency of soil washing. The results revealed that the optimum washing solution was 1% HNO3 and that the removal rates of Cd and Pb were 75.7% and 60.6%, respectively, under treatment conditions of 35 °C, 90 min and a solid-liquid ratio of 1:10. The pH, total phosphorous, available potassium, soil enzyme activities and soil microbial diversity decreased significantly after washing. However, after the neutralization of washed soil with Ca(OH)2, the available phosphorous, total nitrogen and some microorganisms increased significantly compared with those of the soil before washing. After treatment with 1% HNO3, the chemical forms of Cd and Pb in soil mainly existed as F1 (exchangeable) fractions, but the main forms of the two metals changed to F5 (residual) and F3 (bound to Fe-Mn oxides) fractions after neutralization with Ca(OH)2. In addition, the plant height, root length, and fresh and dry weight of M. haplocalyx were not significantly affected by soil neutralization, while the Pb, Cu and As concentrations in the aboveground parts significantly decreased. Therefore, although soil washing could effectively remove Pb and Cd in soil, it also resulted in a significant decline in soil quality, but soil neutralization could effectively alleviate the negative effects during soil washing.

Similarities in Recalcitrant Structures of Industrial Non-Kraft and Kraft Lignin.

This work compares the structure of industrially isolated lignin samples from kraft pulping and three alternative processes: butanol organosolv, supercritical water hydrolysis, and sulfur dioxide/ethanol/water fractionation. Kraft processes are known to produce highly condensed lignin, with reduced potential for catalytic depolymerization, whereas the alternative processes have been hypothesized to impact the lignin less. The structural properties most relevant to catalytic depolymerization are characterized by elemental analysis, quantitative 13 C and 2 D HQSC NMR spectroscopy, gel permeation chromatography, and thermogravimetric analysis. Quantification of the ß-O-4 ether bond content shows partial depolymerization, with all samples having less than 12 bonds per 100 aromatic units. This results in theoretical monomer yields of less than 5 %, strongly suggesting the alternative fractionation processes generate highly condensed lignin structures that are no more suitable for catalytic depolymerization than kraft lignin. However, the different thermal degradation profiles suggest there are physicochemical differences that could be leveraged in other valorization strategies.

Re-investigation of cadmium accumulation in Mirabilis jalapa L.: evidences from field and laboratory.

Mirabilis jalapa L. was identified as a cadmium (Cd) hyperaccumulator, but data were mainly from laboratory conditions. The main aim of the present study was to confirm whether M. jalapa is a Cd hyperaccumulator by field survey and laboratory experiment. The field survey was conducted at 3 sites and 66 samples were collected, and the results showed that although M. jalapa did not exhibit any visible damage when growing on soil containing 139 mg Cd kg-1, a low concentration of Cd (11.85 ± 3.45 mg kg-1) in its leaves was observed. Although the translocation factor (TF) was up to 3.24 ± 0.42, the bioconcentration factor (BCF) was only 0.13 ± 0.07. The Cd accumulation in leaves of Lanping (LP, contaminated site) and Kunming (KM, clean site) populations reached 93.88 and 81.76 mg kg-1 when artificially spiked soil Cd was 175 mg kg-1, respectively. The BCFs of LP and KM populations were 0.55 and 0.48, and the TFs of the two populations were 3.98 and 4.15, respectively. Under hydroponic condition, the Cd concentration in young leaves of LP and KM populations was 78.5 ± 0.8 and 46.3 ± 1.2 mg kg-1 at 5 mg L-1 Cd treatment, respectively. Furthermore, a significantly positive correlation between tissue Cd concentration and total Cd, CaCl2-extractable Cd, and TCLP-Cd (toxicity characteristic leaching procedure) in soil was established. Therefore, M. jalapa had constitutional characteristics for Cd tolerance and accumulation, but it was not a Cd hyperaccumulator.