Effect of capping mode on control of phosphorus release from sediment by lanthanum hydroxide.

The use of in situ active capping to control phosphorus release from sediment has attracted more and more attentions in recent years. It is important to identify the effect of capping mode on the control of phosphorus release from sediment by the in situ active capping method. In this study, the impact of capping mode on the restraint of phosphorus migration from sediment into overlying water (OW) by lanthanum hydroxide (LH) was studied. Under no suspended particulate matter (SPM) deposition condition, LH capping effectively restrained the liberation of endogenous phosphorus into OW during anoxia, and the inactivation of diffusive gradient in thin film-unstable phosphorus (UPDGT) and mobile phosphorus (PMobile) in the topmost sediment served as a significant role in the restraint of endogenous phosphorus migration into OW by LH capping. Under no SPM deposition, although the transformation of capping mode from the single high dose capping to the multiple smaller doses capping had a certain negative impact on the restraint efficiency of endogenous phosphorus liberation to OW by LH in the early period of application, it increased the stability of phosphorus in the static layer in the later period of application. Under SPM deposition condition, LH capping had the capability to mitigate the risk of endogenous phosphorus liberation into OW under anoxia conditions, and the inactivation of UPDGT and PMobile in the topmost sediment was a significant mechanism for the control of sediment phosphorus liberation into OW by LH capping. Under SPM deposition condition, the change in the covering mode from the one-time high dose covering to the multiple smaller doses covering decreased the efficiency of LH to limit the endogenous phosphorus transport into OW in the early period of application, but it increased the performance of LH to restrain the sedimentary P liberation during the later period of application. The results of this work suggest that the multiple LH capping is a promising approach for controlling the internal phosphorus loading in freshwater bodies where SPM deposition often occurs in the long run.

Thermo-optically tunable slot waveguide-based dual mode-splitting resonators with enhanced sharp lineshapes.

Slot waveguide plays an essential role in achieving high-performance on-chip photonic sensors and nonlinear devices. Ideally, slot waveguide features a large evanescent field ratio and strong electric field intensity in the slot, leading to a high waveguide sensitivity. Unfortunately, the microring resonator (MRR) based on the slot waveguide suffers the less steep spectral slope due to the low quality factor induced by the huge optical propagation loss of the slot waveguide. In this work, a novel dual mode-splitting resonator based on the slot waveguide is proposed and demonstrated to steepen the slope of lineshapes. The device is implemented by two racetrack resonators based on a slot waveguide and a feedback waveguide to introduce coherent optical mode interference, which could induce mode-splitting resonance (MR) with sharp asymmetry line shape and large extinction ratio (ER). The proposed device is fabricated by the standard complementary metal-oxide-semiconductor (CMOS) technologies on silicon-on-insulator (SOI) platform, and the characterization results show dual MRs with an ER of 45.0 dB and a slope rate (SR) of 58.3 dB/nm, exhibiting a much steeper lineshape than that of the conventional MRR with slot waveguide. And the resonance can be tuned efficiently by applying various voltages of the TiN microheater. Investigations in dual MRs devices promote many potential applications in the field of optical switching, optical modulating, and on-chip optical sensing.

Genome-wide identification of U-box genes and protein ubiquitination under PEG-induced drought stress in potato.

Protein ubiquitination is one of the most important posttranslational modifications in eukaryotic cells, and it is involved in a variety of biological processes, including abiotic stress response. The ubiquitination modification is highly specific, which depends on the accurate recognition of substrate proteins by ubiquitin ligase. Plant U-box (PUB) proteins are a class of ubiquitin ligases, multiple members of which have shown to participate in water-deficit stress in Arabidopsis and rice. U-box gene family and large-scale profiling of the ubiquitome in potato has not been reported to date, although it is one of the most important food crops. The identified 66 U-box genes from the potato genome database were unevenly distributed on 10 chromosomes. These StPUBs have a large number of tandem repeat sequences. Analysis of gene expression characteristics revealed that many StPUBs responded to abiotic stress. Three hundred and fourteen lys modification sites were identified under PEG-induced drought stress, which were distributed on 200 proteins, with 25 differential ubiquitination modification sites, most of which were up-regulated. The ubiquitination modification in potato protein was enhanced under PEG-induced drought stress, and U-box ubiquitin ligase was involved. This study provides an overall strategy and rich data set to clarify the effects of ubiquitination on potatoes under PEG-induced drought stress and the ubiquitination modification involved in potato U-box genes in response to PEG-induced drought stress.

Distribution and bioaccessibility of polycyclic aromatic hydrocarbons in industrially contaminated site soils as affected by thermal treatment.

Thermal treatment can not only efficiently remove volatile pollutants but also distinctly alter the speciation of organic carbon (C) and the behaviors of residual pollutants in contaminated soils. Here we examined the distribution and bioaccessibility of polycyclic aromatic hydrocarbons (PAHs) in industrially contaminated site soils affected by thermal treatment (temperature ranging of 105-650 â„ƒ) using synchrotron-based infrared microspectroscopy and n-butanol extraction (a mild solvent extractant). In the pristine soils, the sequestration and distribution of PAHs were simultaneously controlled by aromatic C, aliphatic C and clay minerals. Desorption efficiency of PAHs was substantially increased with increasing temperature, whereas the residual PAHs were strongly immobilized within their binding sites evidenced by their dramatically decreased bioaccessibility. Aliphatic and carboxylic C were gradually decomposed and/or carbonized with increasing temperature. In contrast, aromatic C remained relatively recalcitrant during the thermal treatment and was the key controlling factor for the desorption of residual PAHs in the soils with either thermal treatment or n-butanol extraction. This study is the first to visualize the changes in the binding sites and bioaccessibility of PAHs induced by thermal treatment, which have important implications for understanding the sequestration mechanisms of organic pollutants in soil and optimizing the remediation technique.

The impact of dietary iodine intake on lipid metabolism in mice.

The present study has been designed to investigate the impact of dietary iodine intake on lipid metabolism in mice, including iodine deficiency and iodine excess. Different amounts of iodine mixed in the drinking water were continuously administered to mice. The body weights and the levels of urinary iodine were measured 8 months after the treatment. Thyroid hormones in the serum were detected by chemiluminescence immunoassay. Serum total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol and low-density lipoprotein cholesterol (LDL-C) were determined enzymatically by automatic analyzer. Results showed that the urine iodine concentrations paralleled the amounts of iodine intakes. No statistical differences of body weights among different groups were found. The levels of thyroid hormones were dramatically decreased in iodine deficiency while no significant differences were found between iodine excess groups and normal iodine group. In iodine deficiency groups, the levels of TG, TC, and LDL were increased at varying degrees. In iodine excess groups, the levels of TG in the male mice and the levels of TC in the female mice were much lower than normal iodine group. In conclusion, dietary iodine intake may affect the metabolism of serum lipids. Hypothyroid function induced by iodine deficiency may be responsible for the changes of lipids. Higher iodine intake might benefit lipid metabolism.

[The effects of iodine/selenium on the function of antigen presentation of peritoneal macrophages in rats].

OBJECTIVE: To observe the effects of iodine/selenium on the function of antigen presentation of peritoneal macrophages in rats and explore the immunological mechanisms of iodine/ selenium's role in pathogenesis of autoimmune thyroid diseases (AITD). METHODS: Female Lewis rats were randomly divided into four groups including (1) low selenium and normal iodine group (L(sE)N(I)) (2) low selenium and high iodine group (L(Se)H(I)) (3) normal selenium and normal iodine group (N(Se)N(I) ) (4) normal selenium and high iodine group (N(Se)H(I)). All rats were fed by a special diet with lower selenium and iodine in it and drunk ion-free water containing different levels of iodine and selenium for 3 months. Peritoneal macrophages of each group and OVA allergized T cells were prepared and cultured together. Then the function of antigen presentation were estimated by detecting the levels of IL-2 in the culture supernatant. The levels of the expression of co-stimulator CD86 in the spleen of each group were determined by RT-PCR. RESULTS: The level of IL-2 in the supernatant in N(Se)H(I) (43.22 +/- 3.27) pg/ml was much stronger than N(Se)N(I) [the level of IL-2 was (25.74 +/- 2.45) pg/ml, P < 0.05]. The level of IL-2 in L(Se)N(I) (15.79 +/- 2.13) pg/ml was significantly lower than N(Se)N(I) (P < 0.05). The expression of CD86 mRNA in N(Se)H(I) (CD86/beta-actin: 0.52 +/- 0.10) were higher than N(Se)N(I) (CD86/beta-actin: 0.35 +/- 0.04), P < 0.05. CONCLUSIONS: High iodine could promote the presentation function of macrophages to a higher state than normal. Therefore, high iodine intake might become an importantly inducing factor in thyroid autoimmunity. Low selenium could weaken the ability of recognizing and presenting OVA antigen of peritoneal macrophages which might destroy immunological homeostasis and thus the low selenium intake might also become an inducer of AITD.

[Effect on mouse S180 MDR tumour cell expression correlated factorial matter by 70% ethanol with Huanglian Jiedu Tang].

OBJECTIVE: To observe the effect on P170, LRP, TOPO II of S180 tumour MDR mice for matter by 70% ethanol with Huanglian Jiedu Tang, and then discuss the molecular biology base for clinic. METHOD: 18-22 gramme mice were divided into four groups for normal S180 tumour cell group, matter by 70% ethanol with Huanglian Jiede Tang 100 mg x kg(-1) and 50 mg x kg(-1) in random. Each mouse was given S180 cell 0.2 mL by celiac, and after 24 hours give cisplatin for Injective 3 mg x kg(-1), ip, once a week. And give cyclophosphamide and 5-FU 3 mg x kg(-1), ig, once every day. After 15 days, collect lively mice ascites and give it for onefold normal mice. And then repeat before process. At the same time, every group was given corresponding medicine for 0.2 mL x 10 g(-1). The normal group and the model group were given the same cubage water, all together fore weeks. At last observd the P170, LRP, TOPO II by flow cytometry. RESULT: Matter by 70% ethanol with Huanglian Jiedu Tang could obviously reduce the express of P170 and LRP, and the activiation of TOPO II. CONCLUSION: Matter by 70% ethanol with Huanglian Jiedu Tang can intervene the ocurrence of the multi-drug resistance of tumour cells by regulating the biology gene.

[The effect of tetrandrine on the expression of the P170, LRP and TOPO II in S180's tumor cell induced by chemotherapy in the mice with acquired multi-drug resistance].

OBJECTIVE: To observe the effect of tetrandrine on the P170 production expressed by multi-drug resistance gene, lung resistant protein (LRP), and topoisomeras II and elucidate the underlying molecular mechanism. METHOD: Cellular model of multi-drug resistance was established in S180 tumor cell by means of the scheme of PFC chemotherapy at the dosage lower than that with curative effect. P170, LRP and TOPO II were measured by flow cytometry after the mouse model was treated with tetrandrine for 4 weeks. RESULT: tetrandrine obviously reduced the enhancement of express of P170, LRP and the activity of TOPO II in the tumor cells with multi-drug resistance induced by chemotherapy. CONCLUSION: Tetrandrine significantly inhibits the multi-drug resistance of tumor cells induced by chemotherapy via diminishing both the expression of multi-drug resistance gene and the activity of topoisomeras II.

[The study of tetrandrine on reversion of P170 and apoptosis of obtained multi-drug resistance of mice S180's tumour cell].

OBJECTIVE: To observe the effect of tetrandrine on reversion of mice S180's obtained multi-drug resistance tumor cell induced by chemotherapy by PFC. And then discuss the molecular mechanism of it for the use of TCM in clinic to restrain the drug-resistant of chemotherapy, thereby improve the curative effect. METHOD: By the methods of less dosage of chemotherapy PFC, give the mouse cisplatin 3 mg x kg(-1) i.p., once a week; CTX and 5-FU 3 mg x kg(-1) i.g. four weeks, set up the mice models of multi-drug resistance of S180 tumor cell, and then observe the P170, Fas, CD54 and apoposis by flow cytometry. RESULT: Tetrandrine can obviously lower the express of P170 increase the express of Fas and the apoposis of drug resistant tumor cell. And at the same time it can obviously reduce the express of intercellular adhesion molecule (CD54). CONCLUSION: Terandrine, with its adjustment of correlated biotic active matter, can intervene the occurrence of the multi-drug resistance of tumor cells induced by chemotherapy.

[The interference in correlated molecular mechanism obtained multi-drug resistance of mouse S180's tumour cell for different alkaloid].

OBJECTIVE: To observe the base of the interference in correlated biotic active matter obtained multi-drug resistance induced by chemotherapy for different alkaloid, and to supervise the use in clinic to restrain the multi-drug resistant of chemotherapy, and thereby to improve the curative effect. METHOD: After bestowing subter-dosage unite chemotherapeutant to ascites S180 mouse to set up the mouse models of multi-drug resistance of S180 tumour cell, and giving the mouse matrine, terandrine, oxymatrine and berberine hydrooh loride for 4 weeks, the P170, LRP, TOPOII, Fas and apoposis were determined by flow cytometry. RESULT: Matrine and terandrine could obviously reduce the express of P170, LRP and the activation of TOPOII, and increase the ratio of the express of Fas and the apoposis of drug resistant tumour cell. And at the same time it could obviously reduce the express of intercellular adhesion molecule(CD54). CONCLUSION: Matrine and terandrine can interfere in MDR which results from chemotherapeutics by the adjustment of correlated biotic active matter, besides, the different degree of alkaloid effect with different configuration.