Unexpected guests in the tumor microenvironment: microbiome in cancer.

Although intestinal microbiome have been established as an important biomarker and regulator of cancer development and therapeutic response, less is known about the role of microbiome at other body sites in cancer. Emerging evidence has revealed that the local microbiota make up an important part of the tumor microenvironment across many types of cancer, especially in cancers arising from mucosal sites, including the lung, skin and gastrointestinal tract. The populations of bacteria that reside specifically within tumors have been found to be tumor-type specific, and mechanistic studies have demonstrated that tumor-associated microbiota may directly regulate cancer initiation, progression and responses to chemo- or immuno-therapies. This review aims to provide a comprehensive review of the important literature on the microbiota in the cancerous tissue, and their function and mechanism of action in cancer development and treatment.

Snow Depth Estimation on Slopes Using GPS-Interferometric Reflectometry.

Snow is one of the most critical sources of freshwater, which influences the global water cycle and climate change. However, it is difficult to monitor global snow variations with high spatial-temporal resolution using traditional techniques due to their costly and labor-intensive nature. Nowadays, the Global Positioning System Interferometric Reflectometry (GPS-IR) technique can measure the average snow depth around a GPS antenna using its signal-to-noise ratio (SNR) data. Previous studies focused on the use of GPS data at sites located in flat areas or on very gentle slopes. In this contribution, we propose a strategy called the Tilted Surface Strategy (TSS), which uses the SNR data reflected only from the flat quadrants to estimate the snow depth instead of the conventional strategy, which employs all the SNR data reflected from the whole area around a GPS antenna. Three geodetic GPS sites from the Plate Boundary Observatory (PBO) project were chosen in this experimental study, of which GPS sites p683 and p101 were located on slopes with their gradients up to 18% and the site p025 was located on a flat area. Comparing the snow depths derived with the GPS-IR TSS method with the snow depth results provided with the GPS-PBO, i.e., GPS-IR with the conventional strategy, the Snowpack Telemetry (SNOTEL) network measurements and gridded Snow Data Assimilation System (SNODAS) estimates, it was found that the snow depths derived with the four methods had a good agreement, but the snow depth time series with the GPS-IR TSS method were closer to the SNOTEL measurements and the SNODAS estimates than those with GPS-PBO method. Similar observations were also obtained from the cumulative snowfall time series. Results generally indicated that for those GPS sites located on slopes, the TSS strategy works better.

The Role of Excitons on Light Amplification in Lead Halide Perovskites.

The role of excitons on the amplifications of lead halide perovskites has been explored. Unlike the photoluminescence, the intensity of amplified spontaneous emission is partially suppressed at low temperature. The detailed analysis and experiments show that the inhibition is attributed to the existence of exciton and a quantitative model has been built to explain the experimental observations.

Postsynthetic and Selective Control of Lead Halide Perovskite Microlasers.

The control of photoluminescence and absorption of lead halide perovskites plays a key role in their applications in micro- and nano-sized light emission devices and photodetectors. To date, the wavelength controls of lead halide perovskite microlasers are mostly realized by changing the halide mixture in solution. Herein, we report the postsynthetic and selective control of the optical properties of lead halide perovskites with conventional semiconductor technology. By selectively exposing a CH3NH3PbBr3 microstructure with chlorine in inductively coupled plasma, we find that the wavelengths of absorption, photoluminescence, and laser emissions of exposed structures are blue-shifted around 50 nm. Most importantly, the device characteristics such as the photoluminescence intensities and laser thresholds are well maintained during the reaction process. We believe our finding will significantly boost the practical applications of lead halide perovskite based optoelectronics.