Effect of Recession on the Re-entry Capsule Aerodynamic Characteristic

AbstractNumerical simulation and analysis of aerodynamic characteristics of Soyuz ablation shape is carried out in this paper for the adverse influence coming from recession. The result indicates that the shape change caused by the recession will increase absolute value of trim angle of attack and trim lift-drag ratio. The conclusion offers reference for the aerodynamic layout design and improve of the Soyuz re-entry capsule

The Simplified Carbapenem Inactivation Method (sCIM) for Simple and Accurate Detection of Carbapenemase-Producing Gram-Negative Bacilli

This study reports the simplified carbapenem inactivation method (sCIM) to detect carbapenemase-producing gram-negative bacilli in a simple and accurate manner. This method is based on the modified carbapenem inactivation method (mCIM) with the improvement of experimental procedures. Instead of incubating the antibiotic disk in the organism culture media, the organism to be tested was smeared directly onto the antibiotic disk in the sCIM. For evaluating the sensitivity and specificity of the method, a total of 196 Enterobacteriaceae, 73 Acinetobacter baumannii, and 158 Pseudomonas aeruginosa isolates were collected. Polymerase chain reaction (PCR) was used to detect the carbapenemase genes. Phenotypic evaluations were performed using both the sCIM and the mCIM. PCR results showed that, of the 196 Enterobacteriaceae strains, 147 expressed the carbapenemase genes blaKPC−2 (58.5%), blaIMP−4 (21.8%), blaIMP−2 (2.0%), blaVIM−1 (6.1%), blaNDM−1 (10.2%), and blaOXA−48 (1.4%). sCIM results had high concordance with PCR results (99.5%) and mCIM results (100%) with the exception of one Klebsiella pneumoniae strain, which had an minimal inhibitory concentration (MIC) for imipenem of 0.25 mg/L. PCR demonstrated that 53 of the 73 A. baumannii isolates expressed the carbapenemase genes blaOXA−23 (98.1%) and blaVIM−2 (1.8%). sCIM and PCR results corresponded but all A. baumannii isolates were carbapenemase negative by the mCIM. PCR demonstrated that 25 of the 158 P. aeruginosa isolates expressed carbapenemase genes blaVIM−1 (52%), blaVIM−2 (8%), blaVIM−4 (36%), and blaIMP−4 (4%). sCIM results had high concordance with PCR results (100%) and the mCIM results (99.4%) with the exception of one P. aeruginosa isolate that expressed the blaVIM−4 gene. The sCIM offers specificity and sensitivity comparable to PCR but has the advantage of being more user-friendly. This method is suitable for routine use in most clinical microbiology laboratories for the detection of carbapenemase-producing gram-negative bacilli

An Integrated Approach based on Markov Chain and Cellular Automata to Simulation of Urban Land Use Changes

Land use change is one of the most important scientific research themes in the field of global environmental change. Due to the presence of uncertainty and randomness in the real world, it is difficult to simulate land use change exactly. To address the spatial uncertainty and temporal randomness in land use change, we propose a model for simulating land use change based on Markov chain and cellular automata (CA), and describes its application to the simulation of land use changes in the city ofWuhan, China. To simulate the urban land use change, the transition rules of the model were first set by globally restrained conditions, locally restrained conditions and a random variable. And then land use patterns and changes were obtained from classified Landsat TM images. A spatial-temporal transition matrix was constructed from the classified images and was applied to the proposed model for simulating land use changes in the city of Wuhan. The experiment results show the validity and feasibility of the Markov-CA-based model for simulating urban land use change

Variability of Anatomical and Chemical Properties with Age and Height in Dendrocalamus brandisii

Dendrocalamus brandisii is an edible bamboo species found in Southwest China and South Asia. However, there is limited information about the anatomical and chemical information of its culms for its utilization and processing. In this paper, the anatomical and chemical properties of different age culms were determined. There are three vascular bundle types found in its culms. The radial length-to-tangential diameter ratio of vascular bundles varied with culm zone but did not vary with age. The outer diameter of metaxylem vessels showed a similar trend. The fiber length (L), wall thickness (W), and Runkel ratio increased with age, while the fiber length-to-outer diameter ratio (L/D) and lumen diameter (Ld) decreased with age. The chemical properties of D. brandisii also differed with age class and height. The holocellulose and ash content decreased from age 1 to 2 years and then increased at year 3. The acid-insoluble lignin, alcohol-toluene extractives, and silica contents increased with age class, whereas the acid-soluble lignin exhibited the opposite trend. The fiber length and L/D values of D. brandisii suggest it would be suitable material for pulp fibers, but its lignin content was relatively high compared with other bamboo species

Spatial differentiation characteristics of vegetation greening rates and climate attribution in China's arid and semi-arid regions

Since the beginning of the 21st century, vegetation greening in China has continuously increased and ranks among the top globally, especially in the western and northern regions of the country. This study analyzed the characteristics of the greening rates of different vegetation types in China's arid and semi-arid regions in the northwest, using satellite-derived Normalized Difference Vegetation Index (NDVI) data from 2002 to 2021. Furthermore, the study explored the response of greening rates to climate change and its temporal effect. The study found that in the past two decades, the vegetation greening rates in the southeastern region of China's arid and semi-arid areas are higher than that in the northwest. Vegetation change in the arid and semi-arid regions of China exhibits significant spatial heterogeneity in response to climate change. The vegetation greening rates in the southeast of the study area increases with precipitation, while in the northwest, it is promoted by daytime temperature and day-night temperature difference. The greening rates of cultivated vegetation, grassland, and meadow thicket is mainly affected by precipitation, while the greening rates of alpine grassland is mainly affected by day-night temperature difference. In addition, the response of vegetation greening rates to climate in China's arid and semi-arid regions has significant time lag and cumulative effects. Climate changes before the growing season (February to May) can also affect vegetation greening rates during the growing season (June to September). The cumulative climate changes over four months have a greater impact on vegetation greening rate than those over two months. Our study quantified the contribution of climate change to the greening rates of different vegetation types, which can provide references for predicting the dynamic changes of vegetation under future climate change

Forecasting mechanical failure and the 26 June 2018 eruption of Sierra Negra Volcano, Galápagos, Ecuador

Using recent advancements in high-performance computing data assimilation to combine satellite InSAR data with numerical models, the prolonged unrest of the Sierra Negra volcano in the Galápagos was tracked to provide a fortuitous, but successful, forecast 5 months in advance of the 26 June 2018 eruption. Subsequent numerical simulations reveal that the evolution of the stress state in the host rock surrounding the Sierra Negra magma system likely controlled eruption timing. While changes in magma reservoir pressure remained modest (<15 MPa), modeled widespread Mohr-Coulomb failure is coincident with the timing of the 26 June 2018 moment magnitude 5.4 earthquake and subsequent eruption. Coulomb stress transfer models suggest that the faulting event triggered the 2018 eruption by encouraging tensile failure along the northern portion of the caldera. These findings provide a critical framework for understanding Sierra Negra's eruption cycles and evaluating the potential and timing of future eruptions

A Living Eukaryotic Autocementation Kit from Surface Display of Silica Binding Peptides on <i>Yarrowia lipolytica</i>

With the development of civil engineering, the demand for suitable cementation materials is increasing rapidly. However, traditional cementation methods are not eco-friendly enough and more sustainable approach such as biobased cementation is required. To meet such demand, Euk.cement, a living eukaryotic cell-based biological autocementation kit, was created in this work. Through the surface display of different silica binding peptides on the fungus <i>Yarrowia lipolytica,</i> Euk.cement cells can immobilize onto any particles with a silica containing surface with variable binding intensity. Meanwhile, recombinant MCFP3 released from the cells will slowly consolidate this binding of cells to particles. The metabolism of immobilized living cells will finally complete the carbonate sedimentation and tightly stick the particles together. The system is designed to be initiated by blue light, making it controllable. This autocementation kit can be utilized for industrial and environmental applications that fit our concerns on making the cementation process eco-friendly