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Summary: Path planning is a fundamental and critical task in many robotic applications. For energy‐constrained robot platforms, path planning solutions are desired with minimum time arrivals and minimal energy consumption. Uncertain environments, such as wind conditions, pose challenges to the design of effective minimum time‐energy path planning solutions. In this article, we develop a minimum time‐energy path planning solution in continuous state and control input spaces using integral reinforcement learning (IRL). To provide a baseline solution for the performance evaluation of the proposed solution, we first develop a theoretical analysis for the minimum time‐energy path planning problem in a known environment using the Pontryagin's minimum principle. We then provide an online adaptive solution in an unknown environment using IRL. This is done through transforming the minimum time‐energy problem to an approximate minimum time‐energy problem and then developing an IRL‐based optimal control strategy. Convergence of the IRL‐based optimal control strategy is proven. Simulation studies are developed to compare the theoretical analysis and the proposed IRL‐based algorithm. [ABSTRACT FROM AUTHOR]

Tunable transmission lines have a high demand in the 5G wireless communication applications. In this brief, a novel transmission line is presented to control both electrical length and characteristic impedance individually, creating flexible functions. For the first function, the proposed transmission line can perform as a tunable phase shifter with 90° phase tuning range and a low insertion loss variation. For the second function, the proposed transmission line can tune the characteristic impedance from 23 Ω to 145 Ω with a fixed phase delay. The ABCD-matrix method is applied to derive the design equations. For the practical implementation, the varactor equivalent parasitic resistances are considered, and the even-odd mode is applied to re-optimize the proposed two tuning functions. To verify the design theory, an experimental prototype is simulated, fabricated, and measured. Both simulation and measurement results match well with the design theory. [ABSTRACT FROM AUTHOR]

1001 Questions & Answers. Helena Spiteri and David Pickering. Dorling Kindersley, 1995. $16.95. (12-18) Basically this is a perfect book for kids at different levels. Although using the simplest way--question [...]

The Visual Dictionary of Physics. Jack Challoner. Dorling Kindersley, 1995. $16.95. (14-18) I can't believe this! A colorful photograph book is actually a dictionary with thousands of physics terms. As [...]

Prehistoric Journey. Kirk R. Johnson and Richard K. Stucky. Greg Michaels, illus., Rich Wicker, photography. Roberts Rinehart, 1995. paper $19.95 (12-18) This is a terrific book on the prehistory of [...]

What is already known about this topic?, Campylobacter genus bacteria are recognized as some of the leading causes of the bacterial diarrheal illness in both developing and developed countries. Recent pilot surveillance study revealed Campylobacter is the most common pathogen in the diarrheal cases using the enhanced filtration methods in Beijing. One outbreak caused by multi-drug resistant Campylobacter coli ( C. coli ) was identified in 2018., What is added by this report?, This is the first identified gastroenteritis outbreak caused by local Campylobacter jejuni ( C . jejuni ) infection in Beijing. A total of 14 patients were identified from August 23 to 26, 2019. The epidemiological investigation indicated that all of the patients worked at the same factory and the diarrhea happened after the same meal supplied from one company which service the meal delivery. Fourteen C. jejuni isolates were obtained from 12 patients and 2 food workers. Whole Genome Sequencing (WGS) analysis indicated this outbreak was caused by one highly clonal C. jejuni ., What are the implications for public health practice?, Campylobacter is the major foodborne pathogen in the world. Surveillance and risk assessment for Campylobacter infection particularly for Guillain-Barré Syndrome (GBS) associated C. jejuni infection in China should closely monitored., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2020.)

Mycoplasma pneumoniae (M. pneumoniae) is one of the most important pathogens that cause respiratory tract infection in children and adults. In this study, we describe a rapid and sensitive colorimetric loop mediated isothermal amplification (LAMP) method to detect M. pneumoniae. The specificity and sensitivity of this assay were detected with 21 common respiratory pathogens and 39 M. pneumoniae DNA. The sensitivity of LAMP was 100% among 39 M. pneumoniae isolates and the specificity was 100% among 9 members of other Mycoplasma and 12 common respiratory pathogens. The lowest detectable limit (LDL) of this assay was 102 copies, which detected by a series of standard M. pneumoniae DNA. To evaluate the clinical applicability of the LAMP assay, a total of 80 clinical samples were examined by conventional PCR, real-time PCR and the LAMP assays, respectively. The positive rates were 15.0%, 32.5% and 26.3%, respectively. This colorimetric LAMP assay demonstrated a high level of sensitivity comparable with that of conventional PCR for the detection of M. pneumoniae. It is a valuable method for simple, cost-effective and rapid detection of M. pneumoniae in the rural areas and basic clinical of China.

Objective: Our aim is to analyze the exoproteins of the epidemic strain and nonepidemic strain of El Tor Vibrio cholerae., Methods: We separated the exoproteins of two El Tor strains, one epidemic strain N16961 and one nonepidemic strain 92-3, by two dimension electrophoresis. All protein spots were identified by MALDI-TOF (Matrix Assisted Laser Desorption Ionization-Time of Flight) mass spectrometry and database referencing., Results: We identified 49 exoproteins from 206 protein spots in epidemic strain and 42 exoproteins from 236 protein spots in nonepidemic strain. Sixty-eight exoproteins were totally identified in two strains, and the proteins with signal peptides were about 55.88% in total. We classified the exoproteins into 10 subgroups according to their functions. Among them were metabolic enzymes, protein maintenance and folding, protein synthesis and signal transduction proteins, which accounted for 36.76% of all the proteins identified. We identified 11 hypothetical proteins and 2 unknown function proteins with signal peptides at the first time, accounting for 19.12%. Transporter, flagellum components, degradation enzymes, outer membrane proteins and toxin accounted for 14.71%, 11.76%, 10.29%, 5.88%, 1.47% separately., Conclusion: We obtained the exoprotein profiles of epidemic strain and nonepidemic strain of El Tor Vibrio cholerae. The reasons of why the flagellum components without signal peptides that are associated closely with virulence could be released out of the bacteria, and why with high hemagglutinin/protease secretion in nonepidemic strains should be analyzed in the future.