ARTICLE | doi:10.20944/preprints201806.0224.v1
Subject: Environmental And Earth Sciences, Geophysics And Geology Keywords: SBAS; landslide; danba; time-series; displacement
Online: 14 June 2018 (08:44:11 CEST)
Landslide is a sliding movement of rock mass, debris and soil along the slope under the action of gravity. Small Baseline Subset (SBAS) is an established method for the investigation and monitoring of landslide moments. This study focuses on monitoring the long-temporal displacement of mountainous terrain in Danba County, Sichuan Province via SBAS technique, based on 31 scenes of L-band ALOS/PALSAR data from Feb. 2007 to Oct. 2010.The results show that the largest velocity rates in LOS direction are ±120 mm/yr and maximum accumulated displacement is up to -300, which indicates fast movement of the mountainous terrain during the observation time. These results get good consistency against the results of previous study. This demonstrates the strong potential of SBAS technique for monitoring the landslides geohazard.
ARTICLE | doi:10.20944/preprints202305.1539.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Aspergillus sclerotiorum; phenazine 1-carboxylic Acid; biotransformation; 3-hydroxy phenazine 1-carboxylic acid; green chemistry
Online: 23 May 2023 (07:23:23 CEST)
In green chemistry, filamentous fungi are regarded as a kind of robust microorganism for the biotransformation of natural products. Nonetheless, the screening of microorganisms is crucial for the effective biotransformation of natural products such as phenazine compounds. The precursor metabolite of most phenazine derivatives in Pseudomonas spp. is phenazine-1-carboxylic acid (PCA), the key constituent of shenqinmycin, widely used to control rice sheath blight in southern China. In this study, a new fungus strain Aspergillus sclerotiorum was isolated, which can efficiently convert PCA into 3-hydroxy-phenazine 1-carboxylic acid (3-OH-PCA). Moreover, an effective whole cells biotransformation system was constructed by screening optimal reaction conditions and carbon sources. Hence, Aspergillus sclerotiorum exhibited desirable adaptation by consumption of different carbon sources and maximum whole cell biomass (10.6 g/L DCW) was obtained as a biocatalyst from glucose. Optimal conditions for whole-cell biocatalysis of PCA were evaluated, including PCA concentration of 1120 mg/L, pH 7.0, temperature of 25°C, rotation rate 200 rpm and dry cell weight 15 g/L for 60 h, thus 1060 mg/L of 3-OH-PCA was obtained and the conversion efficiency of PCA was 94%. Hence, the results of repeated batch mood revealed that the biotransformation efficiency of fungus pellets reduced with each subsequent cycle but remained stable in all five cycles with the provision of glucose supplement. These findings open the prospective of using filamentous fungi for the whole cell biocatalysis of phenazine in enormous amount and efficient production of 3-OH-PCA. Moreover, these results laid the foundation for further research to disclose the genetic based mechanism of the strain responsible for PCA biotransformation.
ARTICLE | doi:10.20944/preprints202004.0441.v1
Subject: Medicine And Pharmacology, Pulmonary And Respiratory Medicine Keywords: Corona Virus Disease 2019; pulmonary vesicle; prognosis; surgical treatment
Online: 24 April 2020 (12:06:33 CEST)
Background: The Corona Virus Disease 2019 (COVID-19) is spreading globally now. However, the clinical presentation that predict prognosis of the patients are still largely unknow. Methods: We enrolled 393 patients infected with COVID-19 and 30 patients with common pulmonary bulla and reviewed their clinical features to evaluate the potential prognostic value of pulmonary vesicles, especially in the patients with severe symptoms. One COVID-19 patient with vesicles was treated by bullectomy for last resort, and its characteristics of the patient’s perioperative laboratory tests was analyzed. The pathological findings of bullectomy were described and compared with those of common bulla cases. Results: Patients infected with COVID-19 showed more dependence on ventilator, occurrence of super resistant bacteria, and prone to vesicle formation than common bulla (p<0.05). Disease severity is associated with age, sex, and usage of ventilator, ECMO and antibiotics, super resistance bacteria and vesicle formation (p<0.05). The average mortality rate of COVID-19 patients was 4.10% (25.4% in severe patients, 0.00% in mild patients). Interestingly, the mortality rate further increased in severe patients with pulmonary vesicles than those without pulmonary vesicles (35.7% vs 22.4%, p=0.0442). One COVID-19 patient with vesicles underwent bullectomy and had a poor prognosis, who showed diffuse alveolar damage and extensive necrosis in bullectomy specimen. Conclusions: Patients infected with COVID-19 are more prone to form pulmonary vesicles showed on chest CT scans, as an important poor prognosis factor, especially in the severe patients.