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A study on the survival of Lecanicillium lecanii conidia in storage at room temperature was carried out. Firstly, drying methods of conidia powder were compared. Vacuum-freeze drying (VFD) was more suitable for drying conidia as compared to vacuum drying (VD) at room temperature. Vacuum-freeze drying for 24-h resulted in a water content of 5.4%, and a viability, determined as germination of conidia in 2% glucose solution after16 h, was 90.3% and the infection in greenhouse whitefly, Trialeurodes vaporariorum was about 94.7% at a dose of 1×108 conidia/mL. Secondly, the factors influencing viability of conidia stored at room temperature were evaluated in the laboratory. Temperature was the most critical factor influencing conidial storage stability, among the tested factors affecting survival of conidia stored at room temperature for 6 months. Both conidial germination and infection of hosts decreased with storage temperature increasing from 15 to 35°C, and at 35°C the survival of stored conidia for 6 months was near zero. The moisture content of the conidial powder was another major factor influencing viability of stored conidia at room temperature. Conidial powder dried to about 5% moisture content showed higher viability than non-dried conidial powder. For the carriers, clay and charcoal were more suitable for storage of L. lecanii conidia at room temperature. At a room temperature of 25°C, L. lecanii conidia which were dried to 5% water content and mixed with clay or charcoal could retain about 50% survival after 6 months' storage. [ABSTRACT FROM AUTHOR]

It has been demonstrated that Ipomoea batatas (L.) Lam (sweet potato) has greater soil nutrient absorption ability when grown in association with the invasive plant Mikania micrantha Kunth (mile-a-minute), but the competition interaction of the two plant species under different fertilization levels is not well characterized. The current study utilized a de Wit replacement series incorporating three ratios of I. batatas and M. micrantha densities and four different fertilizer levels in 16 m² plots. In mixed culture, the total shoot length, branch, leaf, and biomass of M. micrantha were significantly suppressed (P < 0.05) by I. batatas. With increasing fertilization, total shoot length, branch, leaf, and biomass of I. batatas and M. micrantha were significantly increased, but at a greater rate for I. batatas than for M. micrantha. Relative yield parameters demonstrated that intraspecific competition was less than interspecific competition and that I. batatas had a higher competitive ability than M. micrantha under different fertilization levels. Fertilization significantly impacted the photosynthetic rate (Pn) of these species in June and July, whereas density ratio had greater effect on Pn of both species in August and September. Growth rates of I. batatas were markedly higher than those of M. micrantha in July and August, but less than those of M. micrantha in June and September. The concentrations of soil organic matter, and available N, P, and K in M. micrantha infested soil were significantly greater (P < 0.05) than soils where I. batatas was grown in monoculture, and fertilization levels were reduced by the presence of I. batatas in mixed culture. With increased fertilization, soil nutrient absorption increased, at a greater rate for I. batatas than for M. micrantha. Our results demonstrated that I. batatas could gain greater competitive advantage from enriched fertilization levels than M. micrantha. If I. batatas is incorporated into cropping system rotations, optimal fertilizer levels could be designed using information from our study to produce high I. batatas yields in addition to the benefits of suppressing invasive plants like M. micrantha. [ABSTRACT FROM AUTHOR]

Ipomoea batatas (L.) Lam has been recognized as a very competitive crop against certain farming weeds, but more information is required to support its potential field application. The current study utilized a de Wit replacement series incorporating five ratios of I. batatas and Ageratina adenophora (Spreng.) R. M. King and H. Rob plants in 9 m2 plots in 2018. In monoculture, the main stem length, leafstalk length, leaf area, and biomass of I. batatas were significantly higher than those of A. adenophora. In mixed culture, the plant height, branch, leaf, and biomass of A. adenophora were significantly suppressed (P < 0.05) by I. batatas. The relative yield (RY) of I. batatas was significantly higher than 1.0, and the RY of A. adenophora was significantly less than 1.0 (P < 0.05) in mixed culture, indicating that the intraspecific competition was higher than interspecific competition for I. batatas, but the intraspecific competition was less than interspecific competition for A. adenophora. The competitive balance index of I. batatas demonstrated a higher competitive ability than A. adenophora. The net photosynthetic rate (Pn) of I. batatas and A. adenophora increased gradually from July to September, and then decreased from September to November in all treatments. The Pn of I. batatas was higher than that of A. adenophora in July and August, less than that of A. adenophora from September to November in monoculture, and the Pn of A. adenophora was significantly suppressed (P < 0.05) with increasing proportions of I. batatas in mixed culture after August. The activities of antioxidant enzymes superoxide dismutase, peroxidase and catalase for A. adenophora were significantly reduced (P < 0.05) with increasing proportions of I. batatas in mixed culture. Our results showed that plant growth of A. adenophora was significantly suppressed by I. batatas competition due to certain morphological and physiological advantages of I. batatas. Therefore, I. batatas is a promising replacement control candidate for managing the infestations of A. adenophora, reducing the soil seed bank and seedlings of A. adenophora. [ABSTRACT FROM AUTHOR]

Hepatitis B virus X protein (HBx) critically contributes to the development of hepatocellular carcinoma (HCC). However, the mechanisms by which HBx promotes HCC remain unclear. In the present study, using a combination of gene expression profiling and immunohistochemistry, we found higher levels of SH2 domain-containing 5 (SH2D5) in liver tissue from HBVassociated HCC (HBV-HCC) patients than in adjacent nontumor tissues. Moreover, HBV infection elevated SH2D5 levels, and we observed that HBx plays an important role in SH2D5 induction. We also found that HBx triggers SH2D5 expression through the NF-κB and c-Jun kinase pathways. Employing SH2D5 overexpression or knockdown, we further demonstrate thatSH2D5promotesHCCcell proliferation both in vitro and in vivo. While investigating the mechanism of SH2D5-mediated stimulation of HCC cell proliferation, we noted that HBV induces SH2D5 binding to transketolase (TKT), a pentose phosphate pathway enzyme, thereby promoting an interaction between and signal transducer and activator of transcription 3 (STAT3). Furthermore, HBx stimulated STAT3 phosphorylation at Tyr-705 and promoted the activity and downstream signaling pathway of STAT3 via the SH2D5-TKT interaction. Taken together, our results suggest that SH2D5 is an HBV-induced protein capable of binding to TKT, leading to induction of HCC cell proliferation. [ABSTRACT FROM AUTHOR]

This study determined the accuracy and biases associated with retrieved Moderate Resolution Imaging Spectroradiometer (MODIS) total precipitable water (TPW) data, and it investigated the impact of these data on severe weather simulations using the Weather Research and Forecast (WRF) model. Comparisons of MODIS TPW with the global positioning system (GPS) TPW and radiosonde-derived TPW were carried out. The comparison with GPS TPW over the United States showed that the root-mean-square (RMS) differences between these two datasets were about 5.2 and 3.3 mm for infrared (IR) and near-infrared (nIR) TPW, respectively. MODIS IR TPW data were overestimated in a dry atmosphere but underestimated in a moist atmosphere, whereas the nIR values were slightly underestimated in a dry atmosphere but overestimated in a moist atmosphere. Two cases, a severe thunderstorm system (2004) over land and Hurricane Isidore (2002) over ocean, as well as conventional observations and Special Sensor Microwave Imager (SSM/I) retrievals were used to assess the impact of MODIS nIR TPW data on severe weather simulations. The assimilation of MODIS data has a slightly positive impact on the simulated rainfall over Oklahoma for the thunderstorm case, and it was able to enhance Isidore’s intensity when the storm track was reasonably simulated. The use of original and bias-corrected MODIS nIR TPW did not show significant differences from both case studies. In addition, SSM/I data were found to have a positive impact on both severe weather simulations, and the impact was comparable to or slightly better than that of MODIS data. [ABSTRACT FROM AUTHOR]