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- Author or Editor: P. Wang x
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Fusarium head blight (FHB, caused by Fusarium graminearum) is a severe disease which threatens the yield and quality of harvested grain products, and hence causes major economic losses in wheat (Triticum spp.) and other small grain cereals. One of the infection routes for the pathogen is believed to be through the extruded anther. In order to study the role of the anther on FHB infection, FHB resistance was measured among wheat (Triticum aestivum L.) cultivars with non-extruded infertile anthers in cytoplasmic male sterile (CMS) lines and with extruded fertile anthers in their alloplasmic maintainer lines, and in an unrelated restorer line. We artificially inoculated the lines with F. graminearum (isolate NE 90) at 1.0 × 105 or 2.0 × 105 spores mL−1 for 72 or 96 hours. The results indicated that CMS cultivars were significantly more resistant than the maintainer and restorer cultivars. As the CMS lines differed from the maintainer lines by cytoplasm, anther health, anther extrusion, and seed set, additional experiments are needed to determine the role of each factor in infection. However, this research indicates that fertile anthers most likely are an important part of the infection pathway and of susceptibility to FHB.
This paper develops an instrumental analytical approach for detection of fourteen polycyclic aromatic hydrocarbons (PAHs) in edible oil samples using gel permeation chromatography (GPC) and ultra-high performance liquid chromatography (UHPLC) coupled with diode array detector (DAD), and fluorescence detector (FLD). The GPC was used to remove triglycerides from edible oil samples. The extracted samples were then detected using UHPLC—DAD—FLD. In order to obtain good separation and high reproducibility, the UHPLC—DAD—FLD experimental condition was optimized. The PAHs including three groups of isomeric PAHs can be separated completely in 12 min using BEH Shield RP 18 column with a suitable gradient elution program. The mean recoveries were in the range of 73–110% with an acceptable reproducibility (RSD < 10%, n = 3). During real sample analysis, the method can decrease the chance of false positives with both DAD and FLD being used simultaneously. The results indicate that the approach is simple, easy, and acceptably reproducible, thereby showing great potential as a method for detection of fourteen PAHs contained in edible oil samples.
The essential oil extracted from Nardostachys chinensis Batal (NCB) was analyzed by gas chromatography-mass spectrometry (GC-MS) combined with two chemometric resolution methods (CRM), heuristic evolving latent projections (HELP), and selective ion analysis (SIA). Qualitative analysis was performed by comparing the obtained pure mass spectra with those in National Institute of Standards and Technology (NIST) mass spectra database. Identification of some compounds was assisted by comparison of programmed temperature retention indices (PTRIs). The quantitative results were obtained by overall volume integration (OVI). A total of 69 compounds in the essential oil of N. chinensis Batal were identified, accounting for 93.98% of the total content. The major compounds were (−)-spathulenol, epiglobulol, trans-longipinocarveol, and patchouli alcohol which contribute to the antimicrobial and antioxidant activity. The results showed that the efficiency and reliability were greatly improved by use of chemometric techniques and programmed temperature retention index as assistants of GC-MS in identification of the plant essential oil.
Abstract
The sorption of Eu(III) on calcareous soil as a function of pH, humic acid (HA), temperature and foreign ions was investigated under ambient conditions. Eu(III) sorption on soil was strongly pH dependent in the observed pH range. The effect of ionic strength was significant at pH < 7, and not obvious at pH > 8. The type of salt cation used had no visible influence on Eu(III) uptake on soil, however at low pH values, the influence of anions was following the order: Cl− ≈ NO3 − > ClO4 −. In the presence of HA, the sorption edge obviously shifted about two pH units to the lower pH, whilst in range of pH 6–7, the sorption of Eu(III) decreased with increasing pH because a considerable amount of Eu(III) was present as humate complexes in aqueous phase, then increased again at pH > 11. The results indicated that the sorption of Eu(III) on soil mainly formed outer-sphere complexes and/or ion exchange below pH ~7; whereas inner-sphere complexes and precipitation of Eu(OH)3(s) may play main role above pH ~8.
Abstract
A complex of N,N'-ethylenebis(salicylideneiminato)diaquochromium(III) nitrate, [Cr(salen)(H2O)2]NO3 was characterized and its decomposition mechanism was studied by TG. The IR spectrum and X-ray analysis were examined for the complex. The non-isothermal kinetic data were analyzed by means of the Achar method and the Coats—Redfern method. The most probable kinetic model function was suggested by comparison of the kinetic parameters.
Summary
Calorimetric determination of the total enthalpy changes (ΔH i) of guanidine-denatured lysozyme (Lys) during the adsorption with simultaneously refolding on the surface of hydrophobic interaction chromatography packings was carried out at 250.001C. The measured ΔH iin the circumstances should include the changes in the three fractions: adsorption, dehydration and molecular conformation. It was found that when the unfolded Lys molecules are adsorbed and refold on the surface, entropy-driving caused by the dehydration of Lys mainly dominates the foregoing process. The refolding enthalpies of Lys, ΔΔH iwere found to be 10~100 folds higher than that measured in usual solutions.</o:p>
Abstract
Sorption of Th(IV) on Na-rectorite as a function of pH, ionic strength, soil humic acid (HA) and fulvic acid (FA) are studied under ambient conditions by using a batch technique. The results indicate that the sorption of Th(IV) on Na-rectorite is not only dependent on medium pH values, but also dependent on medium ionic strength and humic substances. Surface complexation and cation competition exchange account for Th(IV) sorption on Na-rectorite. The sorption of Th(IV) on Na-rectorite decreases with the increase on the concentration of NaNO3, Mg(NO3)2 and Ca(NO3)2, and increases with the increasing amount of HA/FA in the suspension/adsorbed on rectorite. Soil HA/FA enhances the sorption of Th(IV) on rectorite at medium pH<4 drastically, but the presence of FA reduces the sorption of Th(IV) at medium pH>6, and HA has no effect on Th(IV) sorption at medium pH>6. An interpretation for the results is attempted, considering the occurrence of different sorption mechanisms.
Abstract
Research on extracted 90Y with di(2-ethylhexyl) orthophosphoric acid (P204) in lipiodol for liver cancer was made to evaluate the stability of extracted 90Y with P204 in lipiodol (90Y-P204-lipiodol) in serum of newly-born cattle and human’s blood. At first, P204 (extractant) was dissolved in lipiodol (organic phase). Secondly, 90Y was extracted to organic phase after adding 90Y solution into test tube with P204 and lipiodol in it. The extracting efficiency with 0.01 mol/l P204 could reach 99.4%. The stability of 90Y-P204-lipiodol has been experimented in physiological saline solution as preparation for further stability experiment. The result indicated that the extracted 90Y lost 0.02%–0.36% in physiological saline solution. The results of further stability experiment showed that loss efficiencies of extracted 90Y after adding newly-born cattle serum 1 hour, 1 day, 3 and 7 days are 3.38%, 3.12%, 4.29% and 6.62%, respectively, and loss efficiencies of extracted 90Y after adding human’s blood 1 hour, 1 day, 3 and 7 days are 2.55%, 5.91%, 7.88% and 5.63%, respectively. Our data also indicated that 90Y is the most possible radioisotope for being extracted with P204 in lipiodol to treat hepatocellular carcinoma, particularly in cases of unresectable liver tumors, since 90Y is available from several commercial sources in clinical quality. We conclude that the stability of 90Y-P204-lipiodol tested with newly-born cattle serum and human’s blood attained great results. 90Y-P204-lipiodol is a kind of potential and exciting pharmaceutical in inerventional therapy for liver cancer and we can carry on the further animal test and clinical trial.
Abstract
To explore the effect of sesamol on the cognition of APP/PS1 mice, 8-week-old APP/PS1 and wild-type male mice were divided into AD model group, AD + sesamol (50 mg kg−1 bw) group, and Control group. Sesamol was orally administered once a day for 5 months. Morris water maze was used to evaluate the learning and memory ability of mice. The number of synapses in the hippocampal neurons was detected by Golgi staining. Nissl staining was used to observe the changes of Nissl bodies in CA1 and CA3 regions of the hippocampus. Western blotting was used to detect the expression of Aβ, SIRT1, BDNF, and p-CREB/CREB in the hippocampus and cortex. Compared with the model group, sesamol decreased the latency period of APP/PS1 mice (P < 0.05) and increased the total number of neuronal dendritic spines in the hippocampal CA3 region, as well as increased the number of Nissl bodies (P < 0.05). Western blotting results showed that sesamol significantly reduced Aβ protein expression in the hippocampus and cortex, increased SIRT1 expression in the cortex, and increased BDNF expression in the hippocampus (P < 0.05). Sesamol improved the learning and memory abilities of APP/PS1 mice probably through increasing the density of neuronal dendritic spines and upregulating the levels of SIRT1 and BDNF.
Abstract
The complex of [Tb2(p-ClBA)6(PHEN)2] [(p-ClBA: p-chlorobenzoate and PHEN: 1,10-phenanthroline) was prepared and characterized by elemental analysis and IR spectroscopy. The thermal behavior of [Tb2(p-ClBA)6(PHEN)2] in dynamic nitrogen atmosphere was investigated by TG-DTG, SEM and IR techniques. By the kinetic method of processing thermal analysis data put forward by Malek et al., it is defined that the kinetic model for the first-step thermal decomposition is SB(m,n). The activation energy E and the pre-exponential factor lnA for this step reaction are 164 kJ mol-1 and 32.80, respectively. The lifetime equation at mass loss of 10% was deduced as lnτ=(-33.0569+20512.36/T by isothermal thermogravimetric analysis.
