16 research outputs found
A novel thermo-mechanical anti-icing/de-icing system using bi-stable laminate composite structures with superhydrophobic surface
A novel anti-icing/de-icing system composed of bi-stable laminate composite structures with superhydrophobic surface and soft electrothermal patch is investigated in this paper. In this system, the superhydrophobic surface has superior performance in anti-icing and de-icing by reducing the adhesion of the ice-skin interface; meanwhile, a thermo-mechanical way to remove ice is conducted by deforming the bi-stable structures using heating actuation method. The superhydrophobic layer is fabricated by decreasing the free energy of copper oxide on the copper surface. The water contact angle of the superhydrophobic surface is tested by an optical contact angle measuring device, which reaches above 155° and the sliding angle is less than 10°. In addition, the microstructure of superhydrophobic layer is characterized by using a scanning electron microscope (SEM) to illustrate the superhydrophobic mechanism. Moreover, outstanding self-cleaning properties and UV-durability are obtained on the prepared surface. Experimental results indicate that the system has good performances in both anti-icing and de-icing processes when working at the subzero temperature. Meanwhile, there is no liquid water left on the surface after the snap-through process of bi-stable structures. Besides, the factors that affect the anti-icing and de-icing performance of system are discussed, including the superhydrophobic property, morphing characteristic of bi-stable laminate composite structures and actuating method. Finally, the finite element method is used to simulate the factors that affect the deformation of bi-stable structures independently, including the single layer thickness, stacking sequence of the laminate and the embedment of the electrothermal alloy
An Alternative Hot Start PCR Method Using a Nuclease-Deficient ExoIII from Escherichia coli.
The Hot Start polymerase chain reaction (Hot Start PCR) is designed to reduce off-target amplification by blocking DNA polymerase extension at room temperature until the desired temperature is reached. In this study, we investigated a new method of Hot Start PCR that uses a modified Escherichia coli Exonuclease III (EcoExoIIIM) by substituting residues in the DNA-binding pocket and catalytic center. The results showed that PCR amplification yield and specificity were significantly promoted by the addition of EcoExoIIIM. We hypothesize that non-specific binding of primers at room temperature is prevented by binding of the primed template by EcoExoIIIM, which is then released from the DNA by heat denaturation before the first PCR cycle. Through this mechanism, PCR would be enhanced by reducing off-target extension at room temperature
An Alternative Hot Start PCR Method Using a Nuclease-Deficient ExoIII from Escherichia coli
Abstract(#br)The Hot Start polymerase chain reaction (Hot Start PCR) is designed to reduce off-target amplification by blocking DNA polymerase extension at room temperature until the desired temperature is reached. In this study, we investigated a new method of Hot Start PCR that uses a modified Escherichia coli Exonuclease III (EcoExoIIIM) by substituting residues in the DNA-binding pocket and catalytic center. The results showed that PCR amplification yield and specificity were significantly promoted by the addition of EcoExoIIIM. We hypothesize that non-specific binding of primers at room temperature is prevented by binding of the primed template by EcoExoIIIM, which is then released from the DNA by heat denaturation before the first PCR cycle. Through this mechanism, PCR would be..
The Clinical Clues of Pulmonary Alveolar Proteinosis: A Report of 11 Cases and Literature Review
Pulmonary alveolar proteinosis (PAP) is a rare interstitial lung disease characterized by the abnormal alveolar accumulation of surfactant components. The diagnosis of PAP can be easily missed since it is rare and lacks specific clinical symptoms. It is of great importance to have a better understanding of the crucial clue to clinically diagnose PAP and take PAP into consideration in the differential diagnosis of interstitial pulmonary diseases or other diseases with similar manifestations. Here, we analyze the clinical characteristics of 11 cases of PAP patients in local hospital and review the relevant literature in order to provide more information in diagnosis and management of PAP. In our observation, cyfra21-1 and neuron-specific enolase (NSE) known as tumor markers probably can be useful serum markers for diagnosis of PAP. As for the method of pathologic diagnosis, open-lung biopsy was the gold standard but now it is less required because findings on examination of bronchoalveolar lavage fluid (BALF) can help to make the diagnosis. We also have deep experience about when and how to carry out lung lavage
The complete chloroplast genome of Siraitia grosvenorii
Siraitia grosvenorii belongs to Cucurbitaceae. It is widely used in beverage raw materials and traditional Chinese medicine. In this study, Illumina sequencing method was used to establish its complete chloroplast (cp) genome. The complete cp genome is 157,132 bp in length, with a large single copy region (LSC) of 92,442 bp and a small single copy region (SSC) of 21,232 bp, which were separated by a pair of inverted repeat (IR) regions of 21,729 bp. The complete cp genome consists of 85 coding sequences (CDS), 39 tRNA, and eight rRNA genes. Phylogenetic analysis showed that S. grosvenorii was clustered into Cucurbitaceae
Dynamic Influence of Wheel Flat on Fatigue Life of the Traction Motor Bearing in Vibration Environment of a Locomotive
Wheel flat can cause a large impact between the wheel and rail and excites a forced vibration in the locomotive and track structure systems. The working conditions and fatigue life of the motor bearings are significantly affected by the intensified wheel–rail interaction via the transmission path of the gear mesh. In this study, a fatigue life prediction method of the traction motor bearings in a locomotive is proposed. Based on the L−P theory or ISO 281 combined with the Miner linear damage theory and vehicle–track coupled dynamics, the irregular loads induced by the track random irregularity and gear mesh are considered in this proposed method. It can greatly increase the accuracy of predictions compared with the traditional prediction models of a rolling bearing life whose bearing loads are assumed to be constant. The results indicate that the periodic impact forces and larger mesh forces caused by the wheel flat will reduce the fatigue life of the motor bearings, especially when the flat length is larger than 30 mm. Using this method, the effects of the flat length and relatively constant velocity of the locomotive are analyzed. The proposed method can provide a theoretical basis to guarantee safe and reliable working for motor bearings
Control of H<sub>2</sub>S generation in simultaneous removal of NO and SO<sub>2</sub> by rotating drum biofilter coupled with Fe<sup>II</sup>(EDTA)
<p>Simultaneous removal of SO<sub>2</sub> and NO from flue gas can be biologically achieved by the rotating drum biofilter with Fe<sup>II</sup>(EDTA) as a solvent. One issue related with this process is the generation of H<sub>2</sub>S. To control its generation, the pathways of H<sub>2</sub>S formation were investigated, and the parametric tests were conducted. The addition of Fe<sup>II</sup>(EDTA) (10 mM) increased the removal efficiency of NO and SO<sub>2</sub>, while the S<sup>2−</sup> concentration decreased from 81 to 3.5 mM. The parametric tests showed that the high NO concentration favored the SO<sub>2</sub> removal and significantly inhibited the H<sub>2</sub>S generation. High-throughput sequencing showed that the dominant denitrifying bacteria were <i>Pseudomonas</i> (9.09%), and the main sulfate-reducing bacteria were <i>Desulfovibrio</i> (5.84%). The long-term operation confirmed that the system could effectively simultaneous perform biological denitrification and desulfurization, and the H<sub>2</sub>S could be controlled.</p
The Clinical Clues of Pulmonary Alveolar Proteinosis: A Report of 11 Cases and Literature Review
Pulmonary alveolar proteinosis (PAP) is a rare interstitial lung disease characterized by the abnormal alveolar accumulation of surfactant components. The diagnosis of PAP can be easily missed since it is rare and lacks specific clinical symptoms. It is of great importance to have a better understanding of the crucial clue to clinically diagnose PAP and take PAP into consideration in the differential diagnosis of interstitial pulmonary diseases or other diseases with similar manifestations. Here, we analyze the clinical characteristics of 11 cases of PAP patients in local hospital and review the relevant literature in order to provide more information in diagnosis and management of PAP. In our observation, cyfra21-1 and neuron-specific enolase (NSE) known as tumor markers probably can be useful serum markers for diagnosis of PAP. As for the method of pathologic diagnosis, open-lung biopsy was the gold standard but now it is less required because findings on examination of bronchoalveolar lavage fluid (BALF) can help to make the diagnosis. We also have deep experience about when and how to carry out lung lavage
Epidemiological landscape of esophageal cancer in Asia: Results from GLOBOCAN 2020
Abstract Background Esophageal cancer (EC) is a global health problem. Asia represents a huge burden of EC globally, and incidence and mortality vary considerably across different Asian regions. Methods Data on incidence, mortality, and preference were extracted from GLOBOCAN 2020. Age‐standardized incidence and mortality rates were calculated overall by sex, age, country, region, and continent. The predicted burden of incidence and mortality in 2040 was calculated based on global demographic projections. Results It was estimated there were 481 552 new cases of and 434 363 deaths from EC in Asia in 2020, accounting for 79.7% and 79.8% of world EC cases and deaths, respectively. EC incidence and mortality in Asia ranked the highest among all continents. Eastern Asia represents the highest age‐standardized world incidence rate (ASWIR) of 12.3 per 100 000 for all Asian regions. Western Asia represents the lowest ASWIR of 1.7 per 100 000, accounting for 0.7% of the globe. There exist obvious differences in epidemiological features in Asian countries, including incidence, mortality, prevalence, and mortality incidence ratio. There is forecast to be up to 781 000 new cases of EC in Asia by 2040, with increasing rates of 63% for incidence and 72% for mortality from 2020. Conclusions Asia has an increasing number of EC cases and deaths. Strategies for targeting in high‐incidence areas, the elderly, and survival should be prioritized to reduce the global EC burden, especially in low‐ and middle‐income countries in Asia