Ammonium addition reduces phosphorus leaching in a long-term mineral or organic fertilized calcareous soil during flooding conditions.

Organic amendment substitutes mineral fertilizers has been proven to increase the organic matter content of soils, which in turn may induce phosphorus (P) mobilization by triggering the redox reaction. However, under flooded conditions according to local agricultural practices, as one of the factors restricting the decomposition of organic matter, the role ammonium plays in P transformation and leaching from soils with different organic matter remains unclear. To address the knowledge gap, the calcareous soils were collected from a long-term field trial (>13 years) containing two treatments with equal P inputs: a long-term mineral fertilization and a long-term organic amendment. Both long-term mineral fertilized soil and long-term organic amended soil were split into ammonium applications or no ammonium applications. A series of column devices were deployed to create flooded conditions and monitor the P leaching from the collected soils. The K-edge X-ray absorption near-edge structure and sequential extraction method were employed jointly to detect soil P fractions and speciation, and the P sorption/desorption characteristics of soil were evaluated by Langmuir fitting. The results showed a reduction of cumulative leached P from soils by 33.2%-43.3% after ammonium addition, regardless of previous long-term mineral fertilization or organic amendment history. A significant enhancement of soil labile P pool (indicated by the H2O-P fraction and NaHCO3-P fraction) after ammonium addition results in the reduction in soil P leaching. The reduced P sorption capacity coupled with the transformation from hydroxyapatite to ß-tricalcium phosphate indicated that the phosphate retention is attributed to the precipitation formation rather than phosphate sorption by soil. The present study highlights that the ammonium addition could affect the phosphate precipitation transformation. This may be attributed to the effect of ammonium addition on the calcium and magnesium ion content and molar ratio in this soil, thereby regulating the form of soil phosphate precipitation. The mechanisms revealed in this study can support developing optimized agricultural management practices to alleviate soil P loss.

Microbiome convergence enables siderophore-secreting-rhizobacteria to improve iron nutrition and yield of peanut intercropped with maize.

Intercropping has the potential to improve plant nutrition as well as crop yield. However, the exact mechanism promoting improved nutrient acquisition and the role the rhizosphere microbiome may play in this process remains poorly understood. Here, we use a peanut/maize intercropping system to investigate the role of root-associated microbiota in iron nutrition in these crops, combining microbiome profiling, strain and substance isolation and functional validation. We find that intercropping increases iron nutrition in peanut but not in maize plants and that the microbiota composition changes and converges between the two plants tested in intercropping experiments. We identify a Pseudomonas secreted siderophore, pyoverdine, that improves iron nutrition in glasshouse and field experiments. Our results suggest that the presence of siderophore-secreting Pseudomonas in peanut and maize intercropped plays an important role in iron nutrition. These findings could be used to envision future intercropping practices aiming to improve plant nutrition.

Gastroesophageal reflux related changes after sleeve gastrectomy and sleeve gastrectomy with fundoplication: A retrospective single center study.

Background: The worsening of gastroesophageal reflux disease (GERD) and "de novo" GERD after laparoscopic sleeve gastrectomy (LSG) is a major concern as it affects the patient's quality of life; the incidence of GERD after LSG is up to 35%. Laparoscopic sleeve gastrectomy with fundoplication (LSGFD) is a new procedure which is considered to be better for patients with morbid obesity and GERD, but there is a lack of objective evidence to support this statement. This study aimed to assess the effectiveness, safety, and results of LSG and LSGFD on patients who were morbidly obese with or without GERD over an average of 34 months follow-up. Methods: Fifty-six patients who were classified as obese underwent surgery from January 2018 to January 2020. Patients who were obese and did not have GERD underwent LSG and patients who were obese and did have GERD underwent LSFGD. The minimum follow-up time was 22 months and there were 11 cases lost during the follow-up period. We analyzed the short-term complications and medium-term results in terms of weight loss, incidence of de novo GERD/resolution of GERD, and remission of co-morbidities with follow-up. Results: A total of 45 patients completed the follow-up and a questionnaire-based evaluation (GERD-Q), of whom 23 patients underwent LSG and 22 patients underwent LSGFD. We had 1 case of leak after LSGFD.No medium or long- term complications. The patient's weight decreased from an average of 111.6 ± 11.8 Kg to 79.8 ± 12.2 Kg (P = 0.000) after LSG and from 104.3 ± 17.0 Kg to 73.7 ± 13.1 Kg (P = 0.000) after LSGFD. The GERD-Q scores increased from 6.70 ± 0.5 to 7.26 ± 1.7 (P = 0.016) after LSG and decreased from 8.86 ± 1.3 to 6.45 ± 0.8 (P = 0.0004) after LSGFD. The incidence of de novo GERD after LSG was 12 (52.2%) at the 12 month follow-up and 7 (30.4%) at the mean 34 (22-48) month follow-up. The remission of reflux symptoms, for patients who underwent LSGFD, was seen in 19 (86.4%) of 22 patients at 12 months and 20 (90.9%) of 22 patients at the mean 34 (22-48) month follow-up. The two groups did not have any significant difference in the effect of weight reduction and comorbidity resolution. Conclusion: The incidence of de novo GERD after LSG is high,LSG resulted in the same weight loss and comorbidity resolution as LSGFD, in patients who are morbidly obese and experience GERD, and LFDSG prevent the occurrence and development of GERD, combination of LSG with fundoplication (LSGFD) is a feasible and safe procedure with good postoperative results,which worthy of further clinical application.

A meta-analysis of arable soil phosphorus pools response to manure application as influenced by manure types, soil properties, and climate.

Manure amendments to agricultural soils is an excellent opportunity for sustainable utilization of agricultural waste while providing multiple benefits to improve soil quality and increase the availability of nutrients to plants, including phosphorus (P). In this study, a meta-analysis of published data from 411 independent observations based on 133 peer-reviewed papers was performed for an in depth understanding of various factors affecting the transformation of soil P pools with manure application. Manure application increased all soil inorganic P (Pi) by 58.0%-282% and organic P (Po) by 65.0%-105%, while decreasing Po/total P (TP), compared to those in unamended soils. Manure types, soil TP, and manure application rates were the important factors that influenced soil P fractions. Elevation of soil labile Pi was more pronounced with compost application, while poultry and pig manure were more beneficial for promoting soil Pi fractions and stable Po contents compared with other manure types. The manure application rate had pronounced effect on increasing the stable Po fractions. The effects of manure application on increasing soil P fractions were greater in soils with lower TP contents as compared to that in high TP soils. Manure effects on enhancing soil labile Pi and moderately labile Pi were greater in acidic soil than that in neutral and alkaline soils. In addition, soil P fractions showed significant correlation with latitude and mean annual precipitation (MAP). By integrating the impacts of manure types, soil properties, and climate, this meta-analysis would help to develop the management of manure application in a specific region of agriculture as well as promote the interpretation of the interfering factors on the soil P fractions changes in the manure-amended soils.

Novel 18F-Labeled Isonicotinamide-Based Radioligands for Positron Emission Tomography Imaging of Glycogen Synthase Kinase-3ß.

Glycogen synthase kinase-3ß (GSK-3ß), a cytoplasmic serine/threonine protein kinase, is involved in several human pathologies including Alzheimer's disease, bipolar disorder, diabetes, and cancer. Positron emission tomography (PET) imaging of GSK-3ß could aid in investigating GSK-3ß levels under normal and pathological conditions. In this study, we designed and synthesized fluorinated PET radioligands starting with recently identified isonicotinamide derivatives that showed potent affinity to GSK-3ß. After extensive in vitro inhibitory activity assays and analyzing U87 cell uptake, we identified [18F]10a-d as potential tracers with good specificity and high affinity. They were then subjected to further in vivo evaluation in rodent brain comprising PET imaging and metabolism studies. The radioligands [18F]10b-d penetrated the blood-brain barrier and accumulated in GSK-3ß-rich regions, including amygdala, cerebellum, and hippocampus. Also, it could be specifically blocked using the corresponding standard compounds. With these results, this work sets the basis for further development of novel 18F-labeled GSK-3ß PET probes.

Influence of π-bridge conjugation on the electrochemical properties within hole transporting materials for perovskite solar cells.

Hole transporting materials (HTMs) play an important role in most efficient perovskite solar cells (PSCs). In particular, donor-π-bridge-donor type oligomers (D-π-D) have been explored extensively as alternative and economical HTMs. In the present work, a series of triphenylamine-based derivatives as alternatives to the expensive Spiro-OMeTAD were explored by using first-principles calculations combined with the Marcus theory. The electronic structures, optical properties and hole mobilities of all the molecules were investigated to reveal the relationship between their charge-transport properties and the π-bridge conjugation. The HOMO levels decrease with the extension of the π-bridge conjugation length, which may lead to higher open-circuit voltages. Moreover, we employed a quantum mechanical (QM) methodology to estimate the carrier mobility for organic crystals. Specifically, an orientation function µΦ (V, λ, r, θ, γ; Φ) is first applied to quantitatively evaluate the overall carrier mobility of HTMs in PSCs. The theoretically calculated results validate that this model predicts the hole mobility of HTMs correctly. More importantly, it is revealed that enhancing the π-bridge conjugation in HTMs can improve the hole mobility, which will definitely improve the performance of PSCs. We hope that our theoretical investigation will offer a reliable calculation method to estimate the charge-transport properties of novel HTMs applied in perovskite solar cells.

Theoretical insights into the effect of a conjugated core on the hole transport properties of hole-transporting materials for perovskite solar cells.

Conjugated bifluorenylidene and naphthalene central cores are introduced into hole-transporting materials DT1 and DT2 to replace the spiro-core of the reported, highly efficient FDT. The effects of the conjugated core on the geometrics, electronic properties and hole transport properties are investigated by using density functional theory coupled with Marcus theory and the Einstein relation. The calculated results show that DT1 (-5.21 eV) and DT2 (-5.23 eV) have lower HOMO levels than FDT (-5.15 eV), which indicates that the perovskite solar cells with conjugated hole-transporting materials can have higher open-circuit voltages. The introduction of the conjugated core is beneficial to the more efficient face-to-face packing pattern of the dimer, resulting in a larger intermolecular electronic coupling. Importantly, it is found that DT1 (1.6 × 10-3 cm2 V-1 s-1) and DT2 (2.7 × 10-2 cm2 V-1 s-1) exhibit relatively higher hole mobilities than FDT (1.3 × 10-4 cm2 V-1 s-1) owing to the larger electronic coupling. Therefore, enhanced hole transport ability can be achieved by switching from the spiro-core to the conjugated core. The present work provides a new strategy to improve the hole transport properties of hole-transporting materials, which will contribute to the development of conjugated small molecules as hole-transporting materials in efficient perovskite solar cells.

Oxygen and indocyanine green loaded phase-transition nanoparticle-mediated photo-sonodynamic cytotoxic effects on rheumatoid arthritis fibroblast-like synoviocytes.

BACKGROUND: Photodynamic therapy and sonodynamic therapy are developing, minimally invasive, and site-specific modalities for cancer therapy. A combined strategy PSDT (photodynamic therapy followed by sonodynamic therapy) has been proposed in this study. Here, we aimed to develop novel biodegradable poly(DL-lactide-co-glycolic acid) phase-transition nanoparticles simultaneously loaded with oxygen and indocyanine green (OI-NPs) and to investigate the cytotoxic effects and the potential mechanisms of OI-NP-mediated PSDT on MH7A synoviocytes. METHODS: The OI-NPs were prepared using a modified double emulsion method and the physicochemical properties were determined. The cellular uptake of OI-NPs was detected by confocal microscopy and flow cytometry. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay, flow cytometry, and Hoechst 33342/propidium iodide double staining were used to determine the cytotoxic effect of OI-NP-mediated PSDT on MH7A cells. Fluorescence microscope and fluorescence microplate reader were used to detect reactive oxygen species (ROS) generation. RESULTS: The OI-NPs were a stable and efficient carrier to deliver oxygen and indocyanine green, and enhanced cellular uptake was observed in MH7A cells with the nanoparticles. OI-NP-mediated PSDT caused more serious cell damage and more evident cell apoptosis, compared with other groups. Furthermore, increased generation of intracellular ROS was detected in MH7A cells treated with PSDT. Interestingly, the OI-NP-mediated PSDT-induced cell viability loss was effectively rescued by pretreatment with the ROS scavenger N-acetylcysteine. CONCLUSION: Multifunctional OI-NPs were successfully developed and characterized for the combined delivery of oxygen and indocyanine green, and OI-NP-mediated PSDT would be a potential cytotoxic treatment for MH7A cells. This study may provide a novel strategy for the treatment of RA and develop a model of theranostic application through phase-transition nanoparticle-mediated PSDT in the future.

Emodin ameliorates high-fat-diet induced insulin resistance in rats by reducing lipid accumulation in skeletal muscle.

Emodin, an anthraquinone derivative isolated from root and rhizome of Rheum palmatum, has been reported to have promising anti-diabetic activity. The present study was to explore the possible mechanism of emodin to ameliorate insulin resistance. Insulin resistance was induced by feeding a high fat diet to Sprague-Dawley rats. The blood glucose and lipid profiles in serum were measured by an enzymatic method, and a hyperinsulinaemic-euglycaemic clamp was used to evaluate insulin resistance. L6 cells were cultured and treated with palmitic acid and emodin. The lipid content was assayed in the soleus muscle and L6 cells by Oil Red O staining. Western blot, qRT-PCR, and immunohistochemical staining were used to detect the following in the rat soleus muscle and L6 cells: protein levels, mRNA levels of FATP1, FATP4, transporter fatty acid translocase (FAT/CD36), and plasma membrane-associated fatty acid protein (FABPpm). We found that blood glucose, triglyceride (TG), total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were significantly decreased in the emodin group. Oil Red O staining and the level of TG in skeletal muscle and L6 cells confirmed that lipid deposition decreased after treatment with emodin. Furthermore, the protein levels and mRNA levels of FATP1 in skeletal muscle and in L6 cells of rats were significantly decreased, yet the protein levels and mRNA levels of FATP4, FAT/CD36 and FABPpm did not drop off significantly. The study suggest that emodin ameliorates insulin resistance by reducing FATP1-mediated skeletal muscle lipid accumulation in rats fed a high fat diet.

[Study on subsurface wastewater infiltration system covered by different turfgrass for domestic sewage treatment].

Domestic sewage was treated with subsurface wastewater infiltration system covered by two different turfgrass, namely, Festuca arundinacea Schres. and Zoysia japonica Steud.. The result shows that all the different systems have good removal rates to COD. The concentration of COD decreased to less than 48 mg x L(-1) from 97-357 mg x L(-1) which achieve the second class criteria specified in Integrated Wastewater Discharge Standard, and there are no prominent difference among different systems. The concentration of NH4(+) -N decreased to less than 0.5 mg x L(-1) from 76.3-125.8 mg x L(-1) which achieve the IV criteria (< or = 0.5 mg x L(-1)) specified in Groundwater Quality Standard, the effluent concentration of NH4(+) -N in naked system are prominently higher than that in system covered by Festuca arundinacea Schres., and there are no prominent difference compared with system covered by Zoysia japonica Steud.. The concentration of TP in different systems decreased to less than 0.05 mg x L(-1) from 3.70-18.42 mg x L(-1) which achieve the II criteria (< or = 0.1 mg x L(-1)) specified in Surfacewater Quality Standard, and there are no prominent difference among different systems. The removal rates of TN and nitrate were all not good enough, the probability which achieve the III criteria (< or = 20 mg x L(-1)) specified in Groundwater Quality Standard are less than one third, and the effluent concentration of TN and nitrate in naked system are prominently higher than that in systems covered by Festuca arundinacea Schres. and Zoysia japonica Steud..

[Optimal operating condition of ICP-aES for determination of soil nutrients extracted by Mehlich 3 through solution simulation].

As a key process of fertilization with soil test, the determination of soil effective nutrients has received great attention in recent years. Based on a series of standard solution mixtures, which simulate the soil nutrients extracted by Mehlich 3 (M3) reagent, the optimal operating condition of ICP-AES was explored in a systematic way. The results show that the 20 key nutrient elements (P, K, Ca, Mg, Na, Fe, Mn, Cu, Zn, Cd, Cr, Pb, Ni, Al, B, Mo, S, Si, Se, and As) in the solutions can be determined correctly and proficiently when ICP-AES is set at 0.80 L x min(-1) of carrier gas flux, with observation height 15 mm and power 1200 W. This study supplies a primary experimental foundation for establishing the determination technique of essential nutrient elements, extracted from soils in China with the general soil-nutrient extractant M3 reagent.