To determine whether Akt activation was sufficient for the transformation of normal prostate epithelial cells, murine prostate restricted Akt kinase activity was generated in transgenic mice (MPAKT mice). Akt expression led to p70 S6K activation, prostatic intraepithelial neoplasia (PIN), and bladder obstruction. mRNA expression profiles from MPAKT ventral prostate revealed similarities to human cancer and an angiogenic signature that included three angiogenin family members, one of which was found elevated in the plasma of men with prostate cancer. Thus, the MPAKT model may be useful in studying the role of Akt in prostate epithelial cell transformation and in the discovery of molecular markers relevant to human disease.

The Moon has a magmatic and thermal history that is distinct from that of the terrestrial planets1. Radioisotope dating of lunar samples suggests that most lunar basaltic magmatism ceased by around 2.9–2.8 billion years ago (Ga)2,3, although younger basalts between 3 Ga and 1 Ga have been suggested by crater-counting chronology, which has large uncertainties owing to the lack of returned samples for calibration4,5. Here we report a precise lead–lead age of 2,030 ± 4 million years ago for basalt clasts returned by the Chang’e-5 mission, and a 238U/204Pb ratio (µ value)6 of about 680 for a source that evolved through two stages of differentiation. This is the youngest crystallization age reported so far for lunar basalts by radiometric dating, extending the duration of lunar volcanism by approximately 800–900 million years. The µ value of the Chang’e-5 basalt mantle source is within the range of low-titanium and high-titanium basalts from Apollo sites (µ value of about 300–1,000), but notably lower than those of potassium, rare-earth elements and phosphorus (KREEP) and high-aluminium basalts7 (µ value of about 2,600–3,700), indicating that the Chang’e-5 basalts were produced by melting of a KREEP-poor source. This age provides a pivotal calibration point for crater-counting chronology in the inner Solar System and provides insight on the volcanic and thermal history of the Moon.

A number of plasmonic devices and applications, such as chemical and biological sensors, plasmon-enhanced solar cells, optical nanoantennas, metamaterials and metasurfaces, require the deposition of plasmonic metal nanocrystals on various substrates. Because the localized plasmon resonance modes, energies and strengths are strongly dependent on the dielectric function of the surrounding environment, the substrate is expected to largely affect the plasmonic properties of supported metal nanocrystals. Therefore, understanding the effects of the substrate on the plasmonic properties of metal nanocrystals and the roles of the involved factors will be crucial for designing various plasmonic devices that are made of metal nanocrystals deposited on different substrates. Herein we report on our study and results of the effects of substrates with distinct dielectric functions on the plasmonic properties of three types of Au nanocrystals. A combination of experiments and numerical simulations shows that the presence of a substrate causes plasmonic shifts as well as the appearance of new plasmon modes. The plasmonic shifts and the emergence of new plasmon modes are found to be dependent on the particle shape of Au nanocrystals and in turn on the fractional particle surface area that is in contact with the supporting substrate. For Au nanospheres and nanorods, plasmonic shifts, less than 100 nm, are observed on the scattering spectra by changing the supporting substrate from indium tin oxide to silicon. In comparison, a giant spectral shift of more than 300 nm is obtained for Au nanoplates. Moreover, silicon substrates induce the emergence of an out-of-plane quadrupolar mode of Au nanoplates, which interacts with an out-of-plane octupolar mode to give rise to a distinct Fano resonance. The Fano resonance is found to become stronger as the thickness of Au nanoplates is decreased. These results are of great importance for understanding the plasmonic properties of noble metal nanocrystals supported on various substrates, and for designing novel plasmonic nanostructures with desired optical properties and functions.

Objectives: This study aimed to evaluate the diagnostic performance of magnetic resonance perfusion-weighted imaging (PWI) as a noninvasive method to assess post-treatment radiation effect and tumor progression in patients with glioma. Methods: A systematic literature search was performed in the PubMed, Cochrane Library, and Embase databases up to March 2020. The quality of the included studies was assessed by the quality assessment of diagnostic accuracy studies 2. Data were extracted to calculate sensitivity, specificity, and diagnostic odds ratio (DOR), 95% Confidence interval (CI) and analyze the heterogeneity of the studies (Spearman correlation coefficient, I 2 test). We performed meta-regression and subgroup analyses to identify the impact of study heterogeneity. Results: Twenty studies were included, with available data for analysis on 939 patients and 968 lesions. All included studies used dynamic susceptibility contrast (DSC) PWI, four also used dynamic contrast-enhanced PWI, and three also used arterial spin marker imaging PWI. When DSC was considered, the pooled sensitivity and specificity were 0.83 (95% CI, 0.79 to 0.86) and 0.83 (95% CI, 0.78 to 0.87), respectively; pooled DOR, 21.31 (95% CI, 13.07 to 34.73); area under the curve (AUC), 0.887; Q∗, 0.8176. In studies using dynamic contrast-enhanced, the pooled sensitivity and specificity were 0.73 (95% CI, 0.66 to 0.80) and 0.80 (95% CI, 0.69 to 0.88), respectively; pooled DOR, 10.83 (95% CI, 2.01 to 58.43); AUC, 0.9416; Q∗, 0.8795. In studies using arterial spin labeling, the pooled sensitivity and specificity were 0.79 (95% CI, 0.69 to 0.87) and 0.78 (95% CI, 0.67 to 0.87), respectively; pooled DOR, 15.63 (95% CI, 4.61 to 53.02); AUC, 0.8786; Q∗, 0.809. Conclusions: Perfusion magnetic resonance imaging displays moderate overall accuracy in identifying post-treatment radiation effect and tumor progression in patients with glioma. Based on the current evidence, DSC-PWI is a relatively reliable option for assessing tumor progression after glioma radiotherapy.

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Glasses cooled from impact melt and vapor are a common component in lunar regolith, carrying important information about protolith composition, regolith formation, and impact flux on the Moon. Interpretations, however, are frequently challenged due to widespread ambiguity in determining their provenances. Regolith samples returned by China's Chang'E-5 mission provide a unique opportunity to study the microscopic mechanism of regolith reworking on the Moon, because as evidenced by the coherent radioisotope ages and petrographic characteristics of basaltic clasts in the regolith, the Chang'E-5 regolith was mainly evolved from local mare materials, containing minor exotic components. Here, we report 153 glass particles larger than 20 μm in diameters that were screened from 500 mg of Chang'E-5 regolith. Most glass particles have rotational shapes and contain structural and/or compositional heterogeneities in interiors, and geochemical analyses reveal a dominant origin as impact melt of local mare materials. Surfaces of the impact glasses are observed to have abundant protruded and dented microstructures, which are classified as different groups based on their morphology and geochemistry. Similar microstructures were observed on impact spherules collected by the Apollo and Luna missions, but those on the Chang'E-5 impact glasses were formed without substantial involvement of exotic ejecta. Microstructures such as silicate melt pancakes that frequently exhibit flow spikes at margins, nano-phase iron-rich mounds that are arranged with semi-equidistant spaces in curves and patches, spatially clustered microcraters that are indicative of secondary impacts, and blunt linear scratches with terminal particles all suggest that regolith reworking mainly occurred among local materials at low speeds.Plain Language Summary Regolith particles on the Moon exhibit an abundance of small-scale surface texture or microstructures that were formed during regolith reworking. Lunar impact glasses are mainly melted from surface regolith, and microstructures on their surfaces record the history of subsequent regolith reworking. The possible contribution of exotic ejecta in regolith gardening is an interesting topic in lunar science. However, resolving this issue has been a persistent difficulty by both remote observations and sample analyses. China's Chang'E-5 mission returned regolith samples from one of the youngest mare units on the Moon, and earlier sample analyses revealed little exotic components. In 500 mg of Chang'E-5 regolith, we handpicked 153 glass particles that are larger than 20 μm. Most of the particles are heterogeneous impact glasses that contain voids and unmelted fragments, and geochemical analyses showed that the remaining structurally homogeneous particles were also impact glasses formed from local regolith. Based on high-resolution microscopic imaging and elemental mapping, we recognized and classified the abundant protruded and dented microstructures on the glass particles. Morphology and crosscutting relationship of t...

The Advanced Himawari Imager (AHI), the primary sensor aboard the Japanese Himawari‐8 geostationary satellite, measures regional aerosol observations with high temporal‐spatial resolution. To improve product quality and scientific applications, we performed a comprehensive evaluation of AHI aerosol products (version 1.0). We compared nearly 2 years (15 July 2015 to 31 June 2017) of AHI aerosol optical depth at 500 nm (AOD500) with AODs from the Aerosol Robotic Network (AERONET) and the Maritime Aerosol Network (MAN). Results showed that, over land, AHI retrievals exhibit a large overall bias of −0.062, with an R of 0.78; over ocean, average bias measured 0.036 (0.051 for MAN), with an R of 0.89 (0.95 for MAN). AHI retrievals collocated with AERONET AODs (τA) showed the following expected AHI AOD errors: (−0.66 × τA + 0.02, −0.34 × τA + 0.16) over land and (−0.24 × τA + 0.03, 0.10 × τA + 0.11) over ocean. AHI retrievals with degraded performance correlated to different regions, angles, aerosol types, and surface types, suggesting that the AHI aerosol algorithm can be improved by changing aerosol optical models, using better cloud filters, and combining multiple methods to estimate ground reflectance. Collocated comparisons of AHI‐MODerate‐resolution Imaging Spectroradiometer‐AERONET demonstrate that, over land, AHI daytime AODs clearly improve when retrievals with a large viewing zenith angle and small scattering angle are excluded.