Search

The study of nanodroplets coalescence is crucial for the development of nanofluid technology and crude oil dehydration. The coalescence behavior of multiple nanodroplets in single electric field, single swirl centrifugal field, and the coupling of electric field and swirl centrifugal field (E&SC coupling fields) was investigated using the molecular dynamics (MD) method. The validation work verified the feasibility of the present MD models. The effects of electric field frequency (f) and strength (E), angular velocity (ω), water content (wt), and component types on the coalescence behavior of multiple nanodroplets were comprehensively investigated. The results show that direct current (DC) field was more suitable for dealing with low wt emulsions, while alternating current (AC) field was more suitable for dealing with high wt emulsions. The swirl centrifugal field with low (high) ω was correspondingly suitable for dealing with low (high) wt emulsions. The coalescence efficiency increased with increasing Re (20–160) and f (0–40 GHz). In addition, not only the large-sized droplets were easy to be formed, but also the small-sized droplets were easy to be removed in the E&SC coupling fields, which can enhance the coalescence efficiency between multiple nanodroplets. The critical CaE of AC&SC coupling fields was improved 18% than DC&SC coupling fields. Finally, the presence of Span-80 (SPAN) molecules increased the coalescence efficiency of multiple nanodroplets and raised the critical CaE to 0.11. The results of this paper can be potentially helpful for the development of high-efficiency electric dehydration technology at microscale. [ABSTRACT FROM AUTHOR]

Electrocoalescence is a time-saving and energy-efficient technology for dehydrating crude oil. The microscopic coalescence mechanism of nanoparticle-laden water droplet pair in the coupling of electric field and flow field was studied by molecular dynamics simulations. The present numerical results agreed well with the experimental work in the literature and the theoretical predictions. The effects of electric field strength and direction, flow field strength and type, droplet intersection angle, and multiple droplets on nanoparticle-laden droplet pair coalescence in the coupling fields were systematically discussed. The results illustrate that four coalescence modes occurred in the coupling of electric field and shearing flow field (E&S coupling fields), and the coalescence efficiencies ranked as: rolling coalescence mode > temporary coalescence mode > stretching mode > slipping mode. Electric fields dominate droplet coalescence, while flow fields enhance droplet coalescence in the coupling fields. Furthermore, parallel direction of electric field and flow field generally leads to high coalescence efficiencies. As to the multiple droplet systems, in the coupling of x-axis electric field and rotating flow field (E&R coupling fields), the coalescence efficiencies ranked as structure I > structure IV > structure III > structure II, whereas, in the y-axis E&R coupling fields, the coalescence efficiencies ranked as structure I > structure III > structure IV > structure II. Finally, the coalescence efficiencies of the E&R coupling fields were always higher than those of the E&S coupling fields. The results will be potentially valuable for optimizing the design of compact and efficient crude oil dehydrators. [ABSTRACT FROM AUTHOR]

Flow instability is the intricate phenomenon in the annular linear induction pump (ALIP) when the pump runs at off-design working condition. A three-dimensional (3D) numerical model is built to simulate the flow in the pump channel. The pump heads at different flow rates are accurately predicted by comparing with experiment. The simulation results show the fluid velocity is circumferentially nonuniform in the pump channel even at the nominal flow rate. The flow in the middle sector continuously decelerates to nearly zero with the reducing flow rate. Reversed flow occurs in the azimuthal plane, followed by vortex flow. The reason for the heterogeneous velocity field is attributed to the mismatch between nonuniform Lorentz force and relatively even pressure gradient. It is seen that the flow in the region of small Lorentz force has to sacrifice its velocity to match with the pressure gradient. An analytic expression of the axial Lorentz force is then developed and it is clearly demonstrated the Lorentz force could be influenced by the profiles of velocity and radial magnetic flux density. The coupling between velocity and magnetic field is studied by analyzing the magnitudes of different terms in the dimensionless magnetic induction equation. It is found the dissipation term is determined by not only the magnetic Reynolds number but also the square of wave number of the disturbance in each direction. The smaller disturbing wave number weakens the dissipating effect, resulting in the larger nonuniform magnetic field and axial Lorentz force. [ABSTRACT FROM AUTHOR]

Background: Due to antibiotic abuse, the problem of bacterial resistance is becoming increasingly serious, and rapid detection of bacterial resistance has become an urgent issue. Because under the action of antibiotics, different active bacteria have different metabolism of heavy water, antibiotic resistance of bacteria can be identified according to the existence of a C-D peak in the 2030-2400 cm-1 range in the Raman spectrum., Methods: To ensure data veracity, a large number of bacteria need to be detected, however, due to the limitation of the field of view of the high magnification objective, the number of single cells in a single field of view is very small. By combining an image stitching algorithm, image recognition algorithm, and processing of Raman spectrum and peak-seeking algorithm, can identify and locate single cells in multiple fields of view at one time and can discriminate whether they are Antimicrobial-resistant bacteria., Results: In experiments 1 and 2, 2706 bacteria in 9 × 11 fields of view and 2048 bacteria in 11 × 11 fields of view were detected. Results showed that in experiment 1, there are 1137 antibiotic-resistant bacteria, accounting for 42%, and 1569 sensitive bacteria, accounting for 58%. In experiment 2, there are 1087 antibiotic-resistant bacteria, accounting for 53%, and 961 sensitive bacteria, accounting for 47%. It showed excellent performance in terms of speed and recognition accuracy as compared to traditional manual detection approaches. And solves the problems of low accuracy of data, a large number of manual experiments, and low efficiency due to the small number of single cells in the high magnification field of view and different peak-seeking parameters of different Raman spectra., Conclusions: The detection and analysis method of bacterial Raman spectra based on image stitching can be used for unattended, automatic, rapid and accurate detection of single cells at high magnification with multiple fields of view. With the characteristics of automatic, high-throughput, rapid, and accurate identification, it can be used as an unattended, universal and non-invasive means to measure antibiotic-resistant bacteria to screen for effective antibiotics, which is of great importance for studying the persistence and spread of antibiotics in bacterial pathogens., Competing Interests: Given his role as Guest Editor, Bei Li had no involvement in the peer-review of this article and has no access to information regarding its peer-review. Full responsibility for the editorial process for this article was delegated to Josef Jampílek. The authors declare no conflict of interest., (© 2023 The Author(s). Published by IMR Press.)

Klebsiella pneumoniae is a primary culprit of antibiotic-resistant nosocomial infections worldwide, and infections caused by NDM-producing strains are a major threat due to limited therapeutic options. The majority of bla NDM cases occur on plasmids; therefore, we explored the relationships between plasmids and bla NDM genes in K. pneumoniae by analyzing the variants of bla NDM , replicon types, conjugative transfer regions of 171 bla NDM -harboring plasmids from 4,451 K. pneumoniae plasmids. Of the nine identified bla NDM variants, bla NDM-1 (73.68%) and bla NDM-5 (16.37%) were the most dominant. Over half of the bla NDM -harboring plasmids of K. pneumoniae were classified into IncF plasmids. IncX3 single-replicon plasmids (46-57 kb) carried genes encoding relaxases of the MOB P family, T4CP genes of the VirD4/TraG subfamily, and VirB-like T4SS gene clusters, which were mainly geographically distributed in China. We found 10 bla NDM -harboring IncN plasmids (38.38-63.05 kb) carrying the NW-type origin of transfer ( oriT ) regions, genes coding for relaxases of MOB F family, genes encoding T4CPs of the TrwB/TraD subfamily, and Trw-like T4SS gene clusters, which were also mainly geographically distributed in China. Moreover, we identified 21 IncC plasmids carrying bla NDM-1 (140.1-329.2 kb), containing the A/C-type oriT s, genes encoding relaxases of MOB H family, genes encoding T4CPs belonging to TrwB/TraD subfamily, and Tra_F-like T4SS gene clusters. The bla NDM -harboring IncC plasmids were widely geographically distributed all over the world, mainly in the United States, China and Viet Nam. These findings enhance our understanding of the diversity of bla NDM -harboring plasmids in K. pneumoniae ., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zeng, Lei, Li, Hua, Li, Zhang, Lin, Zheng, Yang, Dou, Li and Li.)

Objective: The etiology and pathophysiologic mechanism of sudden sensorineural hearing loss are undefined. We will use artificial intelligence and big data methods to explore the correlation between sudden sensorineural hearing loss and serum indices. Method: A total of 1218 patients with sudden deafness admitted to Sun Yat-sen Memorial Hospital were selected as the experimental group, 95 861 healthy subjects were randomly selected as the control group at the same period. Serum biochemical indexes in two groups were collected and analyzed by TreeNet and CART machine learning algorithms, to screen out highly correlated indicators with sudden sensorineural hearing loss and dig out a set of clinical features for people with high risk of sudden sensorineural hearing loss. Result: It was found that high prevalence rate of sudden sensorineural hearing loss is related to eosinophils, reticulocyte and fibrinogen. The areas under the receiver operator characteristic curves（ROC-AUC） were exploited to evaluate the prediction performance of TreeNet model. Overall the TreeNet model has provided high predictive ability by ROC curve, achieving AUC of 0.99, both recall and accuracy rate of 99.90%. Conclusion: There is significant difference between sudden deadness and normal people in serum biochemical indexes. Eosinophil is the first important indicator to distinguish sudden sensorineural hearing loss. Treenet model has important referenced significance for the screening and diagnosis of sudden sensorineural hearing loss., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Objective: To evaluate the effectiveness of recombinant adenovirus p53 injection (rAd2p53) combined with cisplatin plus 5-fluorouracil regimen in treating laryngeal carcinoma., Method: Tumour animal models were established in the back of mice with Hep-2 cell line. Recombinant adenovirus p53 injection (rAd2p53) were transduced to tumor-bearing mouse by direct intratumoral injection combine with cisplatin plus 5-fluorouracil ivgtt. The control group 1 was given recombinant adenovirus p53 injection (rAd2p53) simplex. The control group 2 was administered with cisplatin plus 5-fluorouracil ivgtt simplex. Then compare the diameters of pro-treatment with that of post-treatment and test group with controls., Result: Tumor growth was significantly inhibited following combined rAd2p53 gene therapy with cisplatin plus 5-fluorouracil chemotherapy compared to single rAd2p53 gene therapy and cisplatin plus 5-fluorouracil chemotherapy controls., Conclusion: Local injection of rAd2p53 combined with cisplatin plus 5-fluorouracil chemotherapy is a promising treatment to laryngeal cancer.