Sponge iron enriches autotrophic/aerobic denitrifying bacteria to enhance denitrification in sequencing batch reactor.

Sponge iron (SFe) coupled with a sludge system has great potential for improving biological denitrification; however, the underlying mechanism is not yet fully understood. In this study, the denitrification performance and microbial characteristics of ordinary sludge and SFe-sludge systems were investigated. Overall, the SFe-sludge reactor had faster ammonium degradation rate (94.0 %) and less nitrate accumulation (1.5-53.3 times lower) than ordinary reactor during the complete operation cycle of sequencing batch reactors. The addition of SFe increased the activities of nitrate and nitrite reductases. The total relative abundance of autotrophic denitrifying bacteria (Acidovorax, Arenimonas, etc.) in the SFe-sludge system after 38 days of operation was found to be 10.6 % higher than that in the ordinary sludge reactor. The aerobic denitrifying bacteria (Dokdonella, Phaeodactylibacter, etc.) was 5.3 % higher than ordinary sludge. The SFe-sludge system improved denitrification by enriching autotrophic/aerobic denitrifying bacteria in low carbon-to-nitrogen ratio wastewater treatment.

Study on the Relationship and Predictive Value of First-Trimester Pregnancy-Associated Plasma Protein-A, Maternal Factors, and Biochemical Parameters in Gestational Diabetes Mellitus: A Large Case-Control Study in Southern China Mothers.

Objective: To investigate the relationship and predictive value of first-trimester pregnancy-associated plasma protein A (PAPP-A), maternal factors, and biochemical parameters with gestational diabetes mellitus (GDM) in southern China mothers. Methods: This study recruited 4872 pregnant women. PAPP-A, the free beta subunit of human chorionic gonadotropin (free ß-HCG), fasting plasma glucose (FPG), total cholesterol (TC), triglycerides (TG), and high- and low-density lipoproteins (HDL, LDL) were measured at 11-13+ weeks of gestation. GDM was diagnosed based on a 75 g oral glucose tolerance test at 24-28 weeks of gestation. We performed stepwise logistic regression analysis to determine the odds ratio (OR) and the 95% confidence interval (CI) of GDM. We used Receiver Operating Characteristic (ROC) curves with the area under the curve (AUC) to evaluate the predictive value of PAPP-A, maternal factors, and biochemical markers. The significance of the differences between the AUC values was assessed using the DeLong test. Results: GDM was diagnosed in 750 (15.39%) women. Independent factors for GDM were age, pre-gestational BMI, GWG before a diagnosis of GDM, previous history of GDM, family history of diabetes, FPG, TG, LDL, PAPP-A, and TC. The AUC of PAPP-A was 0.56 (95% CI 0.53-0.58). The AUC of a model based on combined maternal factors, biochemical markers, and PAPP-A was 0.70 (95% CI 0.68-0.72). Differences in AUC values between PAPP-A alone and the model based on combined maternal factors, biochemical markers, and PAPP-A were statistically significant (Z= 9.983, P<0.001). Conclusion: A Low serum PAPP-A level in the first trimester is an independent risk factor for developing GDM later in pregnancy. However, it is not a good independent predictor although the predictive value of a low serum PAPP-A level increases when combined with maternal factors and biochemical markers.

Effects of sponge iron dosage on nitrogen removal performance and microbial community structure in sequencing batch reactors.

The application of sponge iron (SI) carriers can improve the biochemical treatment performance of sequencing batch reactors (SBR) during wastewater treatment. This study used SBR reactors to explore the effects of SI dosage on the nitrogen removal performance and reactor stability and microbial community structure under low temperature and ultra-low load. In contrast to conventional SBR, the average removal rate of total nitrogen (TN) in the biological sponge iron system (BSIS) was increased by 5.38 % for 45 g/L, 18.93 % for 90 g/L, and 13.52 % for 135 g/L, respectively. The nitrogen removal performance and reactor stability showed the best performance under the SI dosage of 90 g/L. The addition of SI formed the anaerobic-anoxic-aerobic microenvironments, which facilitate the propagation of denitrifying bacteria (Saccharimonadales, Hydrogenophaga) and iron bacteria (Rhodoferax and Acinetobacter) in the BSIS. This study provides a new insight on the application of SI in the wastewater treatment.

Association between isolated maternal hypothyroxinemia during the first trimester and adverse pregnancy outcomes in Southern Chinese women: a retrospective study of 7051 cases.

BACKGROUND: The association between isolated maternal hypothyroxinemia (IMH) and adverse pregnancy outcomes is still controversial. This study aimed to evaluate the association between IMH during the first trimester and adverse pregnancy outcomes in southern Chinese women. METHODS: This was a hospital-based, retrospective cohort study. The records of 7051 women, including 1337 IMH women and 5714 euthyroid women who had a singleton pregnancy and accepted routine prenatal service at the Third Affiliated Hospital of Sun Yat-Sen University from January 2015 to September 2018, were extracted from the electronic medical records system in this study. Thyroid functions [thyroid-stimulating hormone (TSH), free thyroxine (fT4) and anti-thyroperoxidase autoantibody (TPO-Ab)] had to be measured before 13 weeks and 6 days of gestation. The chi-square test and multivariate logistic regression analysis were applied to evaluate the association between IMH during the first trimester and adverse pregnancy outcomes. RESULTS: Prepregnancy obesity [prepregnancy body mass index (preBMI) ≥ 25 kg/m2] was found to be more common in the IMH group (11.2% vs. 6.1%) (P < 0.05). The prevalence of gestational diabetes mellitus (GDM), postpartum haemorrhage (PPH), macrosomia and large for gestational age (LGA) was higher in the IMH group. However, after using multivariate logistic regression analysis to adjust for confounders (maternal age, educational levels and preBMI), only LGA was shown to be associated with an increased risk in IMH women [adjusted OR: 1.27 (95% CI 1.044-1.566)]. The prevalence of preterm delivery (either < 37 or < 34 weeks), gestational hypertension, preeclampsia, placenta previa, placental abruption, premature rupture of membrane (PROM), intrauterine growth restriction (IUGR), polyhydramnios, stillbirth, small for gestational age (SGA) and low Apgar score did not increase. CONCLUSION: IMH during the first trimester did not increase any risk of adverse pregnancy outcomes in southern Chinese women except LGA.

Low strength wastewater anammox start-up and stable operation by inoculating sponge-iron sludge: Cooperation of biological iron and iron bacteria.

The application of anaerobic ammonium oxidation (Anammox) technology in low-strength wastewater treatment still faces difficult in-situ start-ups and unstable operations. Sponge-iron sludge (R1) was used as a novel inoculum to provide a promising solution. Conventional activated sludge (R0) was used as the control. However, little is known about the feasibility and performance during the start-up and operation of Anammox combined with biological iron and iron bacteria in an iron sludge system. Anammox was successfully started both in R1 (87 days) and R0 (89 days) with a low-strength influent (with a nitrogen loading rate (NLR) of 43.64 ± 0.41 g N/(m3⋅d)). During long-term operation, the R0 nevertheless produced higher nitrates (9.7 ± 0.1 mg/L) than expected. In contrast, R1 presented no excess nitrate production (2.1 ± 0.06 mg/L). The total inorganic nitrogen (TIN) removal efficiency increased from 78.2 ± 7.1% in R0 to 86.1 ± 4.3% in R1. The iron sludge in R1 was divided equally into three parts and three different nitrogen-feeding methods were used over the 34 days of operation, as follows: first using a mixture of ammonium (27.15 ± 1.0 mg/L) and nitrite (32.7 ± 1.7 mg/L), then only ammonium (27.15 ± 1.0 mg/L) and lastly only nitrite (32.7 ± 1.7 mg/L) as the influent. R1 was a coupled system composed of Anammox, Feammox, and NOx--dependent Fe(II) oxidation (NDFO). The contribution of Feammox and NDFO to TIN removal was 27.1 ± 1.2% and 31.9 ± 0.7%. However, Anammox was the primary nitrogen transformation pathway. X-ray diffraction (XRD) analysis shows that iron hydroxide (Fe(OH)3) and iron oxide hydroxide (FeOOH) were generated in R1. The produced Fe(OH)3 and FeOOH were capable of participating in Feammox and formed a Fe(II)/Fe(III) cycle which further removed nitrogen. Therefore, a highly stable and impressive nitrogen removal performance was demonstrated in the iron sludge Anammox system under the cooperation of biological iron and iron bacteria. The study considered the enrichment of norank_c_OM190, Desulfuromonas, and Thiobacillus and their contribution to the Anammox, Feammox, and NDFO processes, respectively. This study provides a new perspective for the start-up and stable operation of low-strength wastewater Anammox engineering applications.

Structure Characterization, Antioxidant and Immunomodulatory Activities of Polysaccharide from Pteridium aquilinum (L.) Kuhn.

Pteridium aquilinum (L.) Kuhn (Pteridaceae family) has been widely used as a food and medicine in China and Korea. Previous studies indicate that P. aquilinum contains a variety of bioactive chemical components such as flavonoids, phenols, terpenoids, saponins, polysaccharides, and so on. In the present study, a novel polysaccharide (named as PAP-3) with average molecular weight of 2.14 × 105 Da was obtained from P. aquilinum. The structure was studied through physicochemical and spectroscopic analysis. The results indicated that PAP-3 consists of arabinose, rhamnose, fucose, galactose, mannose, and xylose in a molar ratio of 1.58:1.00:3.26:4.57:4.81:3.33. The polysaccharide is mainly composed of (1→2)-linked xylose and (1→3,6)-linked mannose on the main chain, with (1→2)-linked xylose, (1→6)-linked mannose, and (1→6)- and (1→3,6)-linked galactose as side chains. Galactose, fucose, and xylose are located at the end of the side chains. The in vitro immunomodulatory and antioxidant activities were assayed. PAP-3 has strong free-radical scavenging activity on DPPH and ABTS radicals and significant immunomodulatory activity on RAW264.7 cells. These data provide useful information for further study on the polysaccharides of P. aquilinum and their applications in the food and medical industries.

Impact of Early Pregnancy Subclinical Hypothyroidism on Gestational Diabetes Mellitus: A Retrospective Study of 7,536 Cases.

Background: Maternal subclinical hypothyroidism (SCH) has been associated with adverse pregnancy outcomes. This study aimed to explore whether SCH in the first trimester contributed to the development of gestational diabetes mellitus (GDM). Materials and Methods: A total of 8,777 pregnant women who first visited before 13 weeks and 6 days of gestation and accepted routine prenatal service at the Third Affiliated Hospital of Sun Yat-Sen University from January 2015 to September 2018 were recruited in this study. Thyroid functions (thyroid stimulating hormone [TSH], free T4, and thyroid peroxidase antibody [TPOAb]) were measured before 13 weeks and 6 days of gestation and data of 7,536 subjects with TSH ≥0.1 mIU/L were analyzed. A 2-hour 75-g oral glucose tolerance test was performed between 24 and 28 gestational weeks. Chi-square test and multivariate logistic regression analysis were applied to evaluate the relationship between SCH and GDM. Results: The prevalence of SCH in this population was 7.53%. After stratifying the relationship between SCH and GDM according to TSH concentrations (slightly elevated TSH: ≥2.5, <4.0 mIU/L; moderately elevated TSH: ≥4.0, <10.0 mIU/L) and TPOAb status, a moderately elevated TSH combined with positive TPOAb (23.9% vs. normal 13.0%, chi-square = 6.317, p = 0.012) was found to increase the incidence of GDM. Furthermore, after adjusting for confounders (maternal age, educational levels, parity, and pregestational body mass index [preBMI]), the SCH group still exhibited a higher risk of GDM (relative risk [RR] 1.867, 95% confidence interval [CI] 1.018-3.424). Conclusion: Our findings indicated that SCH during early pregnancy, in the presence of moderately elevated TSH levels and positive TPOAb, might lead to an increased risk of GDM.

MiR-101-containing extracellular vesicles bind to BRD4 and enhance proliferation and migration of trophoblasts in preeclampsia.

BACKGROUND: Preeclampsia (PE) is a frequently occurring pregnancy disorder in the placenta, which results in various maternal and fetal complications. The current study aims to evaluate the role of extracellular vesicles (EVs)-encapsulated microRNA (miR)-101 in biological processes of trophoblasts in PE and its underlying mechanism. METHODS: Human umbilical cord mesenchymal stem cell (HUCMSC) and HUCMSC-derived EVs were isolated and cultured, after which EV characterization was carried out using PKH67 staining. In silico analyses were adopted to predict the downstream target genes of miR-101, and dual luciferase reporter gene assay was applied to validate the binding affinity. Furthermore, loss- and gain-of-function approaches were adopted to determine the role of miR-101 and bromodomain-containing protein 4 (BRD4) in trophoblast proliferation and invasion using EDU staining and transwell assay. In addition, a rat model of PE was established to verify the function of EV-encapsulated miR-101 in vivo. RESULTS: Placental tissues obtained from PE patients presented with downregulated miR-101 expression and upregulated BRD4 and CXCL11 expression. EV-encapsulated miR-101 from HUCMSCs could be delivered into the trophoblast HTR-8/SVneo cells, thus enhancing proliferation and migration of trophoblasts. Mechanically, miR-101 targeted and negatively regulated BRD4 expression. BRD4 knockdown promoted the proliferation and migration of trophoblasts by suppressing NF-κB/CXCL11 axis. EV-encapsulated miR-101 from HUCMSCs also reduced blood pressure and 24 h urine protein in vivo, thereby ameliorating PE. CONCLUSION: In summary, EV-encapsulated miR-101 promoted proliferation and migration of placental trophoblasts through the inhibition of BRD4 expression via NF-κB/CXCL11 inactivation.

New Poisson-Sch type inequalities and their applications in quantum calculus.

The Poisson type inequalities, which were improved by Shu, Chen, and Vargas-De-Teón (J. Inequal. Appl. 2017:114, 2017), are generalized by using Poisson identities involving modified Poisson kernel functions with respect to a cone. New generalizations of improved Poisson-Sch type inequalities are obtained by using the generalized Montgomery identity associated with the Schrödinger operator. As applications in quantum calculus, we estimate the size of weighted Schrödingerean harmonic Bergman functions in the upper half space.

Angular distribution of polarized light and its effect on light extraction efficiency in AlGaN deep-ultraviolet light-emitting diodes.

Angular distribution of polarized light and its effect on light extraction efficiency (LEE) in AlGaN deep-ultraviolet (DUV) light-emitting diodes (LEDs) are investigated in this paper. A united picture is presented to describe polarized light's emission and propagation processes. It is found that the electron-hole recombinations in AlGaN multiple quantum wells produce three kinds of angularly distributed polarized emissions and propagation process can change their intensity distributions. By investigation the change of angular distributions in 277nm and 215nm LEDs, this work reveals that LEE can be significantly enhanced by modulating the angular distributions of polarized light of DUV LEDs.

Dependence of the impact response of polyvinylidene fluoride sensors on their supporting materials' elasticity.

Polyvinylidene fluoride (PVDF) is popular sensing material because of its unique piezoelectric characteristics. In this work an impact sensor was prepared from a sandwiched structure PVDF film, and the related detection circuits were presented. The dependence of the PVDF sensors' response on the elasticity of the supporting materials was examined and discussed. Here two response indexes were discussed, which were the peak-to-peak voltage (Vpp) and the recovery time. Firstly, falling impact experiments were executed on desk-supported PVDF sensors (100 mm PVDF film) using free falls of different weights from different heights. Then the same shock experiments were repeated on the same sensor, but changing the backstops to a sponge and rubber, respectively. On the desk, the values of Vpp were bigger than when the other two backstops were used; but the changes of the impact energy could not be reflected by the PVDF sensor when it was supported by a hard material. It was found that the biggest sensitivity of the voltage response (about 96.62 V/J) was obtained by the sponge-supported sensor; for the same sensor, when it was supported by rubber, the slope was 82.26 V/J. Moreover, the recovery time for the desk-supported sensor was almost constant, varying from 0.15 to 0.18 s, while for the same sensor supported by sponge or rubber, its recovery time changed with the shifting of the impact energy in the range of 0.02~0.36 s, but no pattern could be found in the recovery-time characteristics.

Enhancement of surface emission in deep ultraviolet AlGaN-based light emitting diodes with staggered quantum wells.

The optical polarization properties of staggered AlGaN-AlGaN/AlN quantum wells (QWs) are investigated using the theoretical model based on the k·p method. The numerical results show that the energy level order and coupling relation of the valence subband structure change in the staggered QWs and the trend is beneficial to TE polarized transition compared to that of conventional AlGaN/AlN QWs. As a result, the staggered QWs have much stronger TE-polarized emission than conventional AlGaN-based QWs, which can enhance the surface emission of deep ultraviolet (DUV) light-emitting diodes (LEDs). The polarization control by using staggered QWs can be applied in high efficiency DUV AlGaN-based LEDs.

Bio-initiated light addressable potentiometric sensor for unlabeled biodetection and its MEDICI simulation.

A bio-mimetic anchoring strategy based on L-3,4-dihydroxyphenylalanine (L-DOPA) was exploited to activate the surface of light addressable potentiometric sensor (LAPS), with the structure of Si(3)N(4)/SiO(2)/Si. X-Ray photoelectron spectroscopy (XPS) measurements were carried out to ascertain its existence. The protein's immobilization on L-DOPA-initiated LAPS were also tested by our LAPS system. Then L-DOPA-activated LAPS were applied in the unlabeled rabbit anti-mouse immunoglobulin (IgG) detection. The maximum sensitivity of L-DOPA-activated LAPS to antigen (Ag) is about 5.68 nA/p[Ag]. LAPS responses in IgG measurements were from 95 to 180 nA, when the concentration was varied from 0-4 µg mL(-1). These experiments show that L-DOPA is an available material for LAPS surface modifications. At the same time, simulations based on MEDICI (Synopsys™) were performed. The simulated curves are in accordance with experimental data which demonstrate our theoretical analysis for the experimental phenomenon, and indicate the feasibility of simulating biological electronic devices with MEDICI.