RESUMO
This paper demonstrates the successful synthesis of TiO2 with (001) crystal plane; its morphology and structure were characterized using XRD, TEM and Raman spectrometer. The results showed that TiO2 nanosheets were bounded by (001) facets on both the top and bottom. TiO2-001/UV photocatalytic process was proved to be a powerful method for degrading tri(chloro-propyl) phosphate (TCPP) in aqueous solution. Under the given parameters, 95% of TCPP was removed in 360â min. The photodegradation followed the pseudo-first-order kinetic reaction. The reactive species during photocatalytic oxidation of TiO2-001 was mainly hydroxyl radical. TCPP was decomposed into small molecule organics by hydroxyl radicals, along with the release of PO43- and Cl-, and most of these intermediates were eventually degraded into carbon dioxide and water.
Assuntos
Retardadores de Chama , Poluentes Químicos da Água , Fosfatos , Titânio , Raios Ultravioleta , Poluentes Químicos da Água/análiseRESUMO
Phytophthora root and stem rot caused by Phytophthora sojae is a destructive disease that afflicts soybean plants throughout the world. The use of resistant soybean cultivars is the primary means of managing this disease, as well as the most effective and economical approach. There are abundant soybean germplasm resources in China that could be deployed for breeding programs; however, the resistance genes (Rps genes) in most cultivars are unknown, leading to uncertainty concerning which are resistant cultivars for use. The resistance genes Rps1a, Rps1c, and Rps1k prevent root and stem rot caused by most P. sojae isolates within a Chinese field population. This study identified three Rps genes in Chinese domestic soybean cultivars using three related avirulence genes by particle bombardment. The complex genetic diversity of soybean cultivars and P. sojae strains has made it difficult to define single Rps genes without molecular involvement. Gene cobombardment is a method for identifying Rps genes quickly and specifically. We showed that cultivars Dongnong 60 and Henong 72 contained Rps1a, while Hedou 19, Henong 76, 75-3, Wandou 21020, Zheng 196, Wandou 28, Heinong 71, and Wandou 29 all contained Rps1c. The cultivars Jidou 12, Henong 72, Heinong 71, and Wandou 29 contained Rps1k. The cultivar Henong 72 contained both Rps1a and Rps1k, while Wandou 29 and Heinong 71 contained both Rps1c and Rps1k. We then evaluated the phenotype of 11 domestic soybean cultivars reacting to P. sojae using the isolates P6497 and Ps1. The 11 domestic cultivars were all resistant to P6497 and Ps1. This research provides source materials and parent plant strains containing Rps1a, Rps1c, and Rps1k for soybean breeding programs.
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Phytophthora , China , Resistência à Doença , Humanos , Doenças das Plantas , Glycine maxRESUMO
Phytophthora root and stem rot (PRR) caused by Phytophthora sojae is a destructive disease afflicting soybean. The use of resistant cultivars is the most effective method to combat PRR. PRR resistance was assessed in 223 soybean cultivars from Huanghuaihai and Dongbei, major soybean-producing regions in east central and northeastern China. To evaluate levels of soybean resistance to P. sojae, we used eight representative P. sojae isolates and a modified etiolated hypocotyl-slit inoculation method. The cultivars Wandou21020, Xu9302-A, Kedou10, and Lidi055 showed resistance to all eight isolates; 14 cultivars showed intermediate resistance to all eight P. sojae isolates, and 53 cultivars were resistant to seven isolates. Thirty-three cultivars (15%) were susceptible only to the highly virulent PsJS2 isolate, which is consistent with the reactions of the Chapman differential line that carries Rps3a. The diverse reaction patterns seen in germplasm from different regions (provinces/cities) in this study reflect the variety of PRR-resistant soybean sources in China. Our research indicates that sources of P. sojae resistance are present in the major soybean production areas of China. This study provides useful information for soybean breeding programs.
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Phytophthora , China , Resistência à Doença , Humanos , Doenças das Plantas , Proteínas Ribossômicas , Glycine maxRESUMO
BACKGROUND: Interferon-release assays (IGRAs) for diagnosing active pulmonary tuberculosis (PTB) are not yet fully validated, particularly in high TB-endemic areas as the People's Republic of China (PRC). The aim of this report was to assess the performance of the QuantiFERON-TB Gold In-tube (QFT-GIT) and tuberculin skin test (TST), in addition to microbiological results, as contributors for diagnosing active PTB in the PRC. METHODS/PRINCIPAL FINDINGS: A total of 300 PTB patients, 41 disease controls (DC) and 59 healthy community controls (HCC) were included prospectively between May 2010 and April 2011 from two provinces of the PRC (Heilongjiang and Zhejiang). The QFT-GIT and TST yielded an overall sensitivity for active TB of 80.9% and 86.2%, and a specificity of 36.6% and 26.8%, respectively. The province of origin and smear microscopy status did not significantly impact the diagnostic values for PTB. However, using the TST with a 10 mm cut-off point, a significantly higher proportion of LTBI was observed in the DC than the HCC (p=0.01). Discordant results between the QFT-GIT and TST were found among 1/3 of the PTB, HCC and DC. Two-thirds of the individuals presented TST-positive/QFT-GIT-negative discordant results. The TST-negative/QFT-GIT-positive result was not associated with age or bacillary load. Cumulative QFT-GIT and TST positive results increased the overall sensitivity (95.9%), but it was associated with a dramatic decrease of the overall specificity (24.8%) leading to a suboptimal PPV (80.1%) and a low NPV (61.1%). CONCLUSIONS/SIGNIFICANCE: The usefulness of the QFT-GIT to diagnose active TB in high TB-endemic countries remains doubtful because like the TST, the QFT-GIT cannot distinguish between LTBI and active TB. Used as single stand-alone tests, both the QFT-GIT and TST have very limited roles in the diagnosis of active PTB. However, the combined use of SM, the TST and QFT-GIT may allow for the exclusion of ATB.