The ambrosia beetle, Euwallacea interjectus, is a wood-boring pest and a vector of Ceratocystis ficicola, a pathogenic fungus causing fig (Ficus carica) wilt disease (FWD) in Japan. The ambrosia ...fungi, Fusarium kuroshium and Neocosmospora metavorans, have been frequently isolated from heads (including mycangia) of wild and reared adult female E. interjectus, respectively. However, the exact mechanisms driving FWD as well as the interactions between F. kuroshium and C. ficicola in fig orchard remain unclear. To verify the role of the mycangial fungi in the FWD progression, fig saplings were subjected to inoculation treatments (T1, F. kuroshium; T2, N. metavorans, reference positive control; T3, C. ficicola; T4, F. kuroshium + C. ficicola, realistic on-site combination). T3 and T4 saplings began wilting approximately 12 days after inoculation, leading to eventual death. Median duration from inoculation to death of the T4 saplings was approximately four days significantly faster than that of the T3 saplings. Xylem sap-conduction test indicated that dysfunction and necrosis area were considerably wider in the T4 saplings than in T3 saplings. These results demonstrate that the synergistic action of F. kuroshium and C. ficicola contributed to accelerated wilting in the saplings. Based on these discoveries, we proposed a model for system changes in the symbiosis between E. interjectus and its associated fungi in FWD in Japan.
Researches have reported that reactive oxygen species (ROS)-induced oxidative stress plays an important role in cell cryodamage during cryopreservation. In the current study, pollen from
Magnolia ...denudata
and
Paeonia lactiflora
‘Zi Feng Chao Yang’ was cryopreserved and incubated with exogenous catalase (CAT) and malate dehydrogenase (MDH) immediately after thawing. The effect of CAT and MDH on the germination of cryopreserved pollen was measured. Based on that, the ROS level, lipid peroxidation and antioxidants activities in fresh pollen, cryopreserved pollen added with or without CAT or MDH were determined to investigate their relationship with oxidative stress. Pollen from
Magnolia
and
Paeonia
showed a significant loss of germination, but marked increase of ROS and malondialdehyde (MDA) production after cryostorage. Antioxidant profiles in them were also enhanced. CAT and MDH addition increased the post-LN pollen germination of
Magnolia
and
Paeonia
significantly. Their germination rate achieved the highest with 100 IU ml
−1
MDH and 400 IU ml
−1
CAT application, respectively. Compared to their untreated controls, ROS and MDA accumulation reduced significantly in cryopreserved
Magnolia
pollen treated with 100 IU ml
−1
MDH, while superoxide dismutase (SOD) activity improved markedly. In the case of
Paeonia
, significantly lower level of ROS and MDA, but higher activity of CAT and SOD were observed in cryopreserved pollen treated with 400 IU ml
−1
CAT. In conclusion, pollen deterioration after cryopreservation is associated with ROS-induced oxidative stress. Exogenous CAT and MDH can reduce the oxidative damage through the activity stimulation of antioxidant enzymes, and play a protective role in the pollen during cryopreservation.
CdS/TiO
2/polymer nanocomposite thin films (CdS/TiO
2/polymer NTFs) as photocatalyst were prepared and characterized by wide angle X-ray diffraction (WXRD). The effect of key operational factors, ...i.e. catalyst amount, H
2O
2 dosage, solution pH, initial dye concentration, coexisting anions and reuse of catalyst on decolorization of methyl orange (MO) was investigated systematically. WXRD results indicated that CdS/TiO
2/polymer NTFs presented a mixture of anatase TiO
2 and hexagonal CdS nanocrystals. 99.5% of MO was successfully decolorized after 130
min simulated solar light irradiation at 3.9
mmol
L
−1 H
2O
2, 1.0
g
L
−1 CdS/TiO
2/polymer NTFs and pH 6.0 for 15
mg
L
−1 MO aqueous solution. All examined anions (Cl
−, NO
3
−, SO
4
2−, CO
3
2− and PO
4
3−) had an inhibitory effect on the decolorization of MO. When the photocatalyst was used for the fifth time, decolorization efficiency was still about 99% after 130
min irradiation. These results demonstrated that H
2O
2 assisted CdS/TiO
2/polymer NTFs under simulated solar light irradiation was an effective and promising process for decolorization of dye-containing wastewater.
Due to the heterogeneity of rock layers, the poor volumetric sweep efficiency of water and an invalid cycle have emerged as major problems in crude oil production. In this study,
Sporosarcina ...pasteurii
, the ureolytically active microorganisms, and the concentrated substrate were immobilized into the gels while the microorganisms could metabolize to produce ammonium, carbonate and EPS. The optimum immobilization formula was determined according to the microbial activity by detecting the ammonium concentration. Furthermore, the microscope images showed the uniform distribution of the microorganisms in the gels and the porosity of gels was propitious to the immobilization of the microorganisms. The reaction of precipitation happened immediately as soon as the carbonate anion was generated by the microorganisms in the gels and the EPS acted as not only an adhesive agent but also the nucleus of precipitation. As a consequence, the broken gels were healed again
via
the synergistic bridge effect among gel, calcium carbonate and EPS. In addition, the strength analysis revealed the excellent performance of self-healing gel and sand-packed columns experiment showed an improvement of oil recovery from 45.37% to 88.32%. This microbial self-healing gel shows a promising application prospect to enhanced oil recovery.
Due to the heterogeneity of rock layers, the poor volumetric sweep efficiency of water and an invalid cycle have emerged as major problems in crude oil production.
To evaluate the static and dynamic contrast sensitivity changes in myopic patients before and after laser in situ keratomileusis (LASIK).
Seventy-three eyes in 37 patients with myopia (with or ...without astigmatism) who received LASIK were tested for static and dynamic contrast sensitivities using the METRO VISION MON ELEC I system at 0.7, 1.4, 2.7, 5.5, 11, and 22 cpd and cps prior to LASIK, and at one-, three-, and six-month intervals after LASIK.
All eyes gained naked visual acuity of more than 0.5 after LASIK. The contrast sensitivity was depressed at all frequencies 1 month after LASIK, as compared to one week prior to LASIK. The depression at 2.7, 5.5, 11 (P < 0.01) and 22 cpd (P < 0.05) was statistically significant for static contrast sensitivity, and also at 5.5 (P < 0.01) and 11 cps (P < 0.05) for dynamic contrast sensitivity. Myopic eyes between 6.25 D and 14.0 D, and astigmatic eyes 2 DC and more, suffered more static and dynamic contrast sensitivity depression than the myopic eyes between 1.25 D an
Oligomannurarate 971 derived from a marine plant has shown neuroprotective effects. In this study we synthesized a series of truncated derivatives of the oligosaccharide, and investigated the effect ...of these derivatives against Abeta peptide toxicity in vitro. The sulfoxide method was applied to synthesize the derivatives. SH-SY5Y human neuroblastoma cells were treated with Abeta1-40 (2 μmol/L), and the cell viability was detected using a CCK8 assay. A series of beta-(1,4)-D-mannosyl oligosaccharide, ranging from the disaccharide to the hexasaccharide, were synthesized. Addition of 10 μmol/L beta-(1,4)-D-mannobiose 6, beta-(1,4)-D-mannotriose 9 or beta-(1,4)-D-mannotetraose 12 in SH-SY5Y cells significantly attenuated Abeta1-40-induced toxicity. The efficacies were similar to those caused by 10 μmol/L oligomannurarate 971 or alzhemed. Other oligosaccharides including oligomaltoses and oligocelluloses were less active. Synthetic homogeneous short chain beta-(1,4)-D-mannans shows neuroprotective effect against Abeta peptide toxicity similar to that of heterogeneous oligomannurarate 971 and alzhemed.
We used wild-caught Japanese geckos (Gekko japonicus) and captive conspecifics fed with mealworms and fruit flies to study their differences in gut microbial structure and composition and sexual ...correlates of gut microbiota. Gut microbial community richness and diversity were higher in mealworm-fed geckos than in wild geckos. The beta rather than alpha diversity of gut microbiota was sex dependent. From this study, we know the following. First, dietary and sexual correlates of gut microbiota are evident in G. japonicus. Second, with respect to the composition of gut microbiota, G. japonicus is more similar to the common leopard gecko than other reptilian taxa. Third, the diversity of gut microbiota is higher in geckos ingesting food with a higher chitin content. Numerous studies have demonstrated that multiple intrinsic and extrinsic factors shape the structure and composition of gut microbiota in a host. The disorder of the gut microbiota may trigger various host diseases. Here, we collected fecal samples from wild-caught Japanese geckos (Gekko japonicus) and captive conspecifics fed with mealworms (mealworm-fed geckos) and fruit flies (fly-fed geckos), aiming to examine the dietary and sexual correlates of the gut microbiota. We used 16S rRNA gene sequencing technology to determine the composition of the gut microbiota. The dominant phyla with a mean relative abundance higher than 10% were Verrucomicrobiota, Bacteroidota, and Firmicutes. Gut microbial community richness and diversity were higher in mealworm-fed geckos than in wild geckos. Neither community evenness nor beta diversity of gut microbiota differed among wild, mealworm-fed, and fly-fed geckos. The beta rather than alpha diversity of gut microbiota was sex dependent. Based on the relative abundance of gut bacteria and their gene functions, we concluded that gut microbiota contributed more significantly to the host's metabolic and immune functions. A higher diversity of gut microbiota in mealworm-fed geckos could result from higher chitin content in insects of the order Coleoptera. This study not only provides basic information about the gut microbiota of G. japonicus but also shows that gut microbiota correlates with dietary habits and sex in the species.
In this paper, a revisiting Hughes’ dynamic continuum model is used to investigate and predict the essential macroscopic characteristics of pedestrian flow, such as flow, density and average speed, ...in a two dimensional continuous walking facility scattered with a circular obstruction. It is assumed that pedestrians prefer to walk a path with the lowest instantaneous travel cost from origin to destination, under the consideration of the current traffic conditions and the tendency to avoid a high-density region and an obstruction. An algorithm for the pedestrian flow model is based on a cellcentered finite volume method for a scalar conservation law equation, a fast sweeping method for an Eikonal-type equation and a second-order TVD Runge-Kutta method for the time integration on unstructured meshes. Numerical results demonstrate the effectiveness of the algorithm. It is verified that density distribution of pedestrian flow is influenced by the position of the obstruction and the path-choice behavior of pedestrians.
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