Cytochrome P4501B1 (Cyp1b1) is expressed specifically in certain neural crest (NC) cells during embryogenesis. Mesenchymal progenitor cells that develop from NC cells are modeled here by mouse C3H10T1/2 and 3T3-L1 cells. Dexamethasone in combination with methylisobutylxanthine (DM) induces Cyp1b1 and a 6.7 kb mouse Cyp1b1 promoter-luciferase reporter in each cell type prior to adipogenesis. An 18 base sequence (at -6.11 kb) (PaxE) which was essential for this reporter stimulation in 3T3-L1 cells bound the transcription factor Pax6. This is shown by gel mobility shifts and sequence mutations. Heterologous vector expression of Pax6 in 3T3-L1 cells enhanced DM stimulated Cyp1b1 promoter activity through cooperation with two Sp1 sites in the proximal promoter region. Chromatin immunoprecipitation showed that DM stimulated binding of Pax6 adjacent to Sp1 in the proximal promoter more than in the PaxE region. The Cyp1b1 induction by DM in C3H10T1/2 cells was more rapid but independent of Pax6. The far upstream enhancer region (FUER) found in rat Cyp1b1 responded to DM but was inactive in the mouse promoter due to key sequence changes. The expression patterns of Pax6 and Cyp1b1 frequently overlap during mouse embryogenesis. The relationship between Pax6 and Cyp1b1 expression warrants further investigation, particularly in the NC.

Airborne passive interferometric microwave sensors (PIMSs) were proposed as a powerful complementary tool for ship detection, especially in low visibility and high sea clutter environments. At present, there is only one algorithm for ship detection by airborne PIMSs, and this algorithm is only based on the “cold” brightness temperature (TB) characteristic of metal ships with wakes in passive interferometric microwave images (PIMIs). Moreover, it has been found that ship wakes always exhibit a “hot” TB characteristic in PIMIs. In this article, an improved algorithm is innovatively proposed for ship detection by airborne PIMSs to improve detection performance, and it is simultaneously based on the “cold” and “hot” TB characteristics of metal ships with wakes. The microwave TB model of metal ships with wakes is established to analyze its TB characteristics. Given the TB model and its characteristics, an improved algorithm is introduced, which comprises five steps: searching targets, improving TB maps, clustering targets, estimating ship headings, and estimating ship trajectories. The improved algorithm can detect ships with a low false-alarm probability (FAR) and accurately estimate ship headings using only a single snapshot and the ship trajectory. The practicability and detection performance of the improved algorithm is verified by airborne experiments using an X-band PIMS. The experimental results demonstrate that the improved algorithm can accurately detect ships, estimate ship headings using only a single snapshot, and estimate ship trajectories. The impact of the algorithm parameters on the detection performance is analyzed and discussed. Moreover, the detection performance of the improved algorithm is analyzed and compared with the performance of the only existing algorithm, and the experimental results indicate that the improved algorithm has a better detection performance with a lower FAR value than the only existing algorithm, as expected.

Lunar thermal conductivity is significantly important for understanding the geological processes of the Moon. The Apollo in-situ heat flow experiments and Diviner remote sensing data provide us with good constraints on the thermophysical properties of the lunar regolith fines layer. As the first farside in-situ experiments, Chang’E-4 (CE-4) temperature sensors will further extend our understanding. In this study, a one-dimensional thermal model with updated bulk densities by the CE-4 Lunar Penetrating Radar (LPR) data is used. Then, the nighttime surface temperatures from the sensors of the CE-4 lander are applied to retrieve the surface thermal conductivity at the CE-4 landing site. After minimizing the differences between the predicted temperature and CE-4 measurements, the range of surface layer contact conductivity ( k_s ) within the upper 1 cm is about (0.95 ~ 2.26) × 10 ^-3 Wm ^-1 K ^-1 for T1, (1.04 ~ 2.44) × 10 ^-3 Wm ^-1 K ^-1 for T2, (0.60 ~ 1.40) × 10 ^-3 Wm ^-1 K ^-1 for T3, and (0.60~1.39) × 10 ^-3 Wm ^-1 K ^-1 for T4, respectively. In addition, the factors that may affect the inversion or the measurements were discussed, such as the shadowing effect, the rock abundance, the lateral conduction from the rover transfer mechanism, and the densification effect during the measurements.

A microwave radiation model with coherent surface scattering is developed for analyzing the topographic effects of the lunar permanently shadowed region (PSR) on microwave radiometric observations. The coherent surface scattering to the observer, which comes from the nearby surface due to the variation of the surface slope, is quantified by the ray-tracing method. In addition, the vertical distribution of temperatures of the PSR is estimated by a one-dimensional thermal model with three-dimensional shading and scattering effects. The impact of coherent scattering on microwave brightness temperatures by a nadir-look radiometer becomes more noticeable with high-resolution microwave brightness temperature data, such as 4 pix/deg by 4 pix/deg in this study. The rise in brightness temperature at certain locations in PSR may reach up to ~8 K at 37 GHz. However, when compared with the low resolution of the brightness temperature by Chang’E-2, the averaged contribution of coherent surface scattering is less than 1 K. Meanwhile, there is a discrepancy between the model-generated microwave TB and the measured TB of Chang’E-2, both in small and large craters. This discrepancy may be explained by a calibration issue or the uncertainty of model parameters. Nonetheless, the trend in the model-generated brightness temperature is consistent with the measurements, indicating that the proposed model has the potential to predict brightness temperature effectively within the permanently shadowed region.

The vertical temperature distribution in the permanently shaded region (PSR) has a significant impact on the temporal and spatial distribution of the cold trap. To obtain the vertical temperature profile of the PSR, an inversion method that fuses microwave and infrared brightness temperature ( TB ) data is proposed. In the inversion process, the infrared data were initially employed to derive the optimal value of the H-parameter that controls the density profile. Subsequently, high-frequency (37 GHz and 19.35 GHz) microwave TB data were employed to ascertain the range of surface density, whereas low-frequency (3 GHz) microwave TB data were utilized to determine the range of bottom density. A fixed correction was applied to the 3 GHz brightness temperature data to account for the calibration error. Due to the inherent uncertainties associated with the thermal model, both the Hayne and Woods models were employed in the inversion process, yielding disparate results. The PSR in the Haworth impact crater was selected as a case study for the inversion. The Woods model was found to provide a superior explanation for the microwave observation. The optimal surface density of the PSR of the Haworth crater was determined to be within the range of 1200~1300 kg m ^-3 , while the bottom density was within the range of 2100~2200 kg m ^-3 . The inverted vertical temperature distribution in the PSR of Haworth crater indicates that the depth of the cold trap can reach approximately 8.5 m. Additionally, the impact of heat flow on microwave TB is discussed.

Researches have demonstrated that Passive interferometric microwave sensors (PIMSs) can be used in the imagery acquired and target detections, especially in low visibility and/or high sea clutter environments. The target detection by PIMSs is based on the high contrast against the background in the brightness temperature (TB) maps, and it is found that the targets still exhibit a high contrast within the alias field of view (FOV) of the background cancellation TB maps obtained by a background cancelling method in the target detection algorithm. As a result, the targets can also be detected within the alias FOV of PIMSs, and PIMSs exhibit a wider FOV for target detection than that for Earth’s remote sensing. However, the effective FOV of PIMSs has never been studied for target detection before. In this article, the effective FOV of PIMSs is first studied for target detection. The effective FOV of PIMSs is analyzed and discussed for target detection in theory, which is based on the FOV of PIMSs for Earth’s remote sensing and the background cancelling method. Numerical simulations are performed to analyze the effective FOV of PIMSs in terms of the metallic with a “cold” TB characteristic and the island with a “hot” TB characteristic. A series of experiments have been performed to verify the effective FOV of the PIMSs for target detection that ships, islands, and aircrafts. Both numerical and experimental results have demonstrated that the effective FOV of the PIMSs for target detection based on the background cancelling method can be extended to the central hexagonal regions (H), and it exhibits a wider FOV than alias-free FOV (AF-FOV) and/or Extended alias-free FOV (EAF-FOV) in Earth’s remote sensing, as expected.