Analysis of the Behrens-Fisher Problem Based on Bayesian Evidence

The Behrens-Fisher problem concerns the inferences for the difference between the means of two normal populations without making any assumption about the variances. Although the problem has been extensively studied in the literature, researchers cannot agree on its solution at present. In this paper, we propose a new method for dealing with the Behrens-Fisher problem in the Bayesian framework. The Bayesian evidence for testing the equality of two normal means and a credible interval at a specified level for the difference between the means are derived. Simulation studies are carried out to evaluate the performance of the provided Bayesian evidence

Testing Normal Means: The Reconcilability of the P

The problem of reconciling the frequentist and Bayesian evidence in testing statistical hypotheses has been extensively studied in the literature. Most of the existing work considers cases without the nuisance parameters which is not the frequently encountered situation since the presence of the nuisance parameters is very common in practice. In this paper, we consider the reconcilability of the Bayesian evidence against the null hypothesis H0 in terms of the posterior probability of H0 being true and the frequentist evidence against H0 in terms of the P value in testing normal means where the nuisance parameters are present. The reconcilability of evidence can be obtained both for testing a normal mean and for the Behrens-Fisher problem

High-throughput screening of rare metabolically active tumor cells in pleural effusion and peripheral blood of lung cancer patients

Malignant pleural effusion (MPE), the presence of malignant cells in pleural fluid, is often the first sign of many cancers and occurs in patients with metastatic malignancies. Accurate detection of tumor cells in pleural fluid is crucial because the presence of MPE denotes an advanced stage of disease and directs a switch in clinical managements. Cytology, as a traditional diagnostic tool, has limited sensitivity especially when tumor cells are not abundant, and may be confounded by reactive mesothelial cells in the pleural fluid. We describe a highly sensitive approach for rapid detection of metabolically active tumor cells in MPE via exploiting the altered glucose metabolism of tumor cells relative to benign cells. Metabolically active tumor cells with high glucose uptake, as evaluated by a fluorescent glucose analog (2-NBDG), are identified by high-throughput fluorescence screening within a chip containing 200,000 addressable microwells and collected for malignancy confirmation via single-cell sequencing. We demonstrate the utility of this approach through analyzing MPE from a cohort of lung cancer patients. Most candidate tumor cells identified are confirmed to harbor the same driver oncogenes as their primary lesions. In some patients, emergence of secondary mutations that mediate acquired resistance to ongoing targeted therapies is also detected before resistance is manifested in the clinical imaging. The detection scheme can be extended to analyze peripheral blood samples. Our approach may serve as a valuable complement to cytology in MPE diagnosis, helping identify the driver oncogenes and resistance-leading mutations for targeted therapies

(Section A: Planning Strategies and Design Concepts)

This paper introduces a comprehensive framework that assesses the urban heat environment and formulates urban wind paths. Compared with other ecosystems, the wind environment and heat environment in urban areas can be much more complicated and dynamic. Nonetheless, it is of great concern considering the agglomerated population and industries at stake. Hence, multiple computational techniques are developed to assess the contemporary heat environment, and to formulate feasible policies to improve it to a more liveable state by introducing the solution of natural wind. Three key factors are considered: solar radiation, which is the major source of heat; wind direction and wind speed, which transports heat in space; and urban land surface, which may affect radiation reflection, contain auxiliary heat sources or cause vertical air flow. Hence, mesoscale meteorological data are applied to provide information about solar radiation, and are used for simulating local wind flow; Landsat images can be translated into land surface temperature figures; and building and land use databases provide information about built-up features. These combined, the local heat environment in urban areas can be mapped and monitored in a periodic fashion, with wind path analysis providing possibilities in cooling down the hotspots. Practices in cities including Fuzhou and Wuhan have proved constructive, with some others still underway

Field Emission Properties and Fabrication of CdS Nanotube Arrays

A large area arrays (ca. 40 cm2) of CdS nanotube on silicon wafer are successfully fabricated by the method of layer-by-layer deposition cycle. The wall thicknesses of CdS nanotubes are tuned by controlling the times of layer-by-layer deposition cycle. The field emission (FE) properties of CdS nanotube arrays are investigated for the first time. The arrays of CdS nanotube with thin wall exhibit better FE properties, a lower turn-on field, and a higher field enhancement factor than that of the arrays of CdS nanotube with thick wall, for which the ratio of length to the wall thickness of the CdS nanotubes have played an important role. With increasing the wall thickness of CdS nanotube, the enhancement factorβdecreases and the values of turn-on field and threshold field increase

Mapping of spatiotemporal auricular electrophysiological signals reveals human biometric clusters

Underneath the ear skin there are rich vascular network and sensory nerve branches. Hence, the 3D mapping of auricular electrophysiological signals can provide new biomedical perspectives. However, it is still extremely challenging for current sensing techniques to cover the entire ultra-curved auricle. Here, a 3D graphene-based ear-conformable sensing device with embedded and distributed 3D electrodes for full-auricle physiological monitoring is reported. As a proof-of-concept, spatiotemporal auricular electrical skin resistance (AESR) mapping is demonstrated for the first time, and human subject-specific AESR distributions are observed. From the data of more than 30 ears (both right and left ears), the auricular region-specific AESR changes after cycling exercise are observed in 98% of the tests and are clustered into four groups via machine learning-based data analyses. Correlations of AESR with heart rate and blood pressure are also studied. This 3D electronic platform and AESR-based biometrical findings show promising biomedical applications

The effect of COVID-19 restrictions on atmospheric new particle formation in Beijing

During the COVID-19 lockdown, the dramatic reduction of anthropogenic emissions provided a unique opportunity to investigate the effects of reduced anthropogenic activity and primary emissions on atmospheric chemical processes and the consequent formation of secondary pollutants. Here, we utilize comprehensive observations to examine the response of atmospheric new particle formation (NPF) to the changes in the atmospheric chemical cocktail. We find that the main clustering process was unaffected by the drastically reduced traffic emissions, and the formation rate of 1.5 nm particles remained unaltered. However, particle survival probability was enhanced due to an increased particle growth rate (GR) during the lockdown period, explaining the enhanced NPF activity in earlier studies. For GR at 1.5-3 nm, sulfuric acid (SA) was the main contributor at high temperatures, whilst there were unaccounted contributing vapors at low temperatures. For GR at 3-7 and 7-15 nm, oxygenated organic molecules (OOMs) played a major role. Surprisingly, OOM composition and volatility were insensitive to the large change of atmospheric NOx concentration; instead the associated high particle growth rates and high OOM concentration during the lockdown period were mostly caused by the enhanced atmospheric oxidative capacity. Overall, our findings suggest a limited role of traffic emissions in NPF.Peer reviewe

Research and Exploration on the Reform of Engineering Training Mode

This paper discusses the reform of engineering training mode to improve teaching quality and effectiveness. The current problems, such as the disconnection between theory and practice and insufficient student ability training, are analyzed. The proposed reform measures include enhancing practical teaching, innovating course settings, establishing engineering laboratories and practice bases, and strengthening student ability training. This paper emphasizes the importance of the reform of engineering training mode as a trend and future direction of higher education. Only through continuous reform and innovation can we better adapt to social changes and make greater contributions to cultivating high-quality engineering talents. Schools, teachers, and students should work together to optimize course settings, focus on practical teaching, and improve the practical effectiveness of courses. In conclusion, this paper provides a comprehensive analysis of the reform of engineering training mode, highlighting the importance of practical teaching and student ability training. Practical and effective reform measures and methods are proposed, providing useful insights for the cultivation of high-quality engineering talents

Maize MeJA-responsive proteins identified by high-resolution 2-DE PAGE

Exogenous methyl jasmonate (MeJA) is well-known to induce plant defense mechanisms effective against a wide variety of insect and microbial pests. High-resolution 2-DE gel electrophoresis was used to discover changes in the leaf proteome of maize exposed to MeJA. We sequenced 62 MeJA-responsive proteins by tandem mass spectroscopy, and deposited the mass spectra and identities in the EMBL-EBI PRIDE repository under reference number PXD001793. An analysis and discussion of the identified proteins in relation to maize defense against Asian corn borer is published by Zhang et al. (2015) [1]