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The ever-increasing space exploration enterprise calls for novel and high-quality radiation-resistant materials, among which nonlinear optical materials and devices are particularly scarce. Two-dimensional (2D) materials have shown promising potential, but the radiation effects on their nonlinear optical properties remain largely elusive. We previously fabricated 2D bismuthene for mode-locking sub-ns laser; herein, their space adaption was evaluated under a simulated space radiation environment. The as-synthesized thin layers of bismuthene exhibited strong third-order nonlinear optical responses extending into the near-infrared region. Remarkably, when exposed to 60Co γ-rays and electron irradiation, the bismuthene showed only slight degradation in saturable absorption behaviors that were critical for mode-locking in space. Ultrafast spectroscopy was applied to address the radiation effects and damage mechanisms that are difficult to understand by routine techniques. This work offers a new bottom-up approach for preparing 2D bismuthene, and the elucidation of its fundamental excited-state dynamics after radiation also provides a guideline to optimize the material for eventual space applications.

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Artificial photosynthesis converting carbon dioxide into chemical fuels with a high added value is a promising solution to both fossil fuel shortage/pollution and global climate change; however, the development of highly efficient photocatalysts toward this goal is still largely bereft of fresh ideas. Herein, we propose a “cascade electron transfer” strategy through spurring both interfacial and inner electron transfer rates for a 0D/2D photocatalyst of CsPbBr3/CuTCPP metal organic framework (MOF). Upon photoexcitation, the heterojunction structure with an appropriate band alignment facilitates an ultrafast interfacial electron transfer rate of 1.4 ps from CsPbBr3 segment to CuTCPP MOF and subsequent ultrafast internal electron transfer of 21 ps from CuTCPP ligand to the Cu node within the enlarged 2D framework. The efficient electron transfer ensures efficient charge separation favorable for photocatalytic reactions: The photocatalyst exhibits an outstanding yield of 47.2 μmol g−1 h−1 (CO and CH4 combined) superior to previous reports. Rational design of hierarchical heterojunctions with matching electronic bandgap not only expedites cascade charge transfer but also prevents holes from recombining with electrons or oxidizing the photocatalysts without the necessity of sacrificial reagents. This work thus provides useful insight for boosting photocatalytic efficacy from a dynamic perspective.

Cell morphology and nucleus deformation are important when circulating tumor cells break away from the primary tumor and migrate to a distant organ. Cells are sensitive to the microenvironment and respond to the cell-material interfaces. We fabricated TiO nanorod arrays with mesoscopic micro-nano interfaces through a two-step hydrothermal reaction method to induce severe changes in cell morphology and nucleus deformation. The average size of the microscale voids was increased from 5.1 to 10.5 μm when the hydrothermal etching time was increased from 3 to 10 h, whereas the average distances between voids were decreased from 0.88 to 0.40 μm. The nucleus of the MCF-7 cells on the TiO nanorod substrate that was etched for 10 h exhibited a significant deformation, because of the large size of the voids and the small distance between voids. Nucleus defromation was reversible during the cells proliferate process when the cells were cultured on the mesoscopic micro-nano interface.This reversible process was regulated by combining of the uniform pressure applied by the actin cap and the localized pressure applied by the actin underneath the nucleus. Cell morphology and nucleus shape interacted with each other to adapt to the microenvironment. This mesoscopic micro-nano interface provided a new insight into the cell-biomaterial interface to investigate cell behaviors.

Determination of the presence and number of circulating tumor cells (CTCs) in peripheral blood can provide clinically important data for prognosis and therapeutic response patterns. In this study, a versatile supersandwich cytosensor was successfully developed for the highly sensitive and selective analysis of CTCs using Au-enwrapped silica nanocomposites (Si/AuNPs) and three-dimensional (3D) microchips. First, 3D microchips were fabricated by a photolithography method. Then, the prepared substrate was applied to bind graphene oxide, streptavidin and biotinylated epithelial-cell adhesion-molecule antibody, resulting in high stability, bioactivity, and capability for CTCs capture. Furthermore, horseradish peroxidase and anti-CA153 were co-linked to the Si/AuNPs for signal amplification. The performance of the cytosensor was evaluated with MCF7 breast cancer cells. Under optimal conditions, the proposed supersandwich cytosensor showed high sensitivity with a wide range of 10(1) to 10(7) cells per mL and a detection limit of 10 cells per mL. More importantly, it could effectively distinguish CTCs from normal cells, which indicated the promising applications of our method for the clinical diagnosis and therapeutic monitoring of cancers.

We introduce a micropillar-based microfluidic device for efficient and rapid cancer cell capture. The microfluidic chip consists of two linear arrays of micropillars integrated with a herringbones flow-derived microstructure, and the separation distance between two adjacent micropillars is similar to the size of tumor cells. Cancer cells can be forced to come into contact with the micro-columns and are then captured by specific immune antibody-antigen interactions. Both previously published data and new available experimental data confirm the superiority of the proposed device. Different cancer cell lines were utilized to investigate the capture efficiency of our microfluidic device. MCF-7 cancer cells spiked into DMEM culture medium can be captured from a suspension with over 90% efficiency. The results of the present work provide a promising method for separation of rare cells, such as circulating tumor or fetal cells.

Climate is an essential element in agricultural production, and climate change inevitably have an impact on agriculture. Assessing the economic consequences of climate change requires comprehensive assessments of the impact chain from climate to crops and the economy. In our previous study, we derived a dose-response function to estimate the response of crop yields to climate variables through a systematic review. In this paper, a dynamic multiregional input-output model is established to assess the economic consequences of changes in agricultural production on China's regional and sectoral levels. The results show that (1) the direct economic damage is equivalent to 1% of gross domestic product (GDP) which implies the resulting economic cascade effect (ECE) that amounts to 17.8% of China's GDP. At the end of 21st century, the ECE is −0.1% to 13.6% of GDP (negative values indicate economic gains) without considering CO 2 fertilization effect, of which the ECE in the most pessimistic pathway are equivalent to the total agricultural output in China today. (2) Regional-level results show an uneven distribution of economic impact in China, which is related to the regional economic development. The least developed region in China experiences 2.8 to 8.5 times more ECE caused by climate change than the most developed region. (3) Sector-level results show that agriculture is still the main affected sector, but in developed regions, manufacturing and services also bear part of the ECE. Plain Language Summary Evidence from numerous studies has confirmed the impact of climate change on agriculture. This paper assesses the economic consequences of changes in agricultural production under climate change in China. We find that the direct economic damage is equivalent to 1% of gross domestic product which implies the resulting economic cascade effect that amounts to 17.8% of total gross domestic product. The most pessimistic estimate of the economic impacts in the 2090s is equivalent to China's total agricultural output today without considering CO 2 fertilization effect of climate change. The economic impacts suffered by different regions of China are related to regional economic development. The least developed region in China experiences more economic damage from climate change than the most developed region. In addition to the agricultural sector, manufacturing and services are expected to experience part of the impacts, especially in developed regions. This paper hopes to provide data support for a comprehensive understanding of climate change impacts in different regions of China by assessing the economic consequences.