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A diabetic wound causes thousands of infections or deaths around the world each year, and its healing remains a critical challenge because of the ease of multidrug-resistant (MDR) bacterial infection, as well as the intrinsic hyperglycemic and hypoxia microenvironment that inhibits the therapeutic efficiency. Herein, we pioneer the design of a photobiocatalytic cascade nanoreactor via spatially organizing the biocatalysts and photocatalysts utilizing a hydrogen-bonded organic framework (HOF) scaffold for diabetic wound therapy. The HOF scaffold enables it to disperse and stabilize the host cargos, and the formed long-range-ordered mesochannels also facilitate the mass transfer that enhances the cascade activity. This integrated HOF nanoreactor allows the continuous conversion of overexpressed glucose and H

Crystallization of biomacromolecules-metal-organic frameworks (BMOFs) allows for orderly assemble of symbiotic hybrids with desirable biological and chemical functions in one voxel. The structure-activity relationship of this symbiotic crystal, however, is still blurred. Here, we directly identify the atomic-level structure of BMOFs, using the integrated differential phase contrast-scanning transmission electron microscopy, cryo-electron microscopy and x-ray absorption fine structure techniques. We discover an obvious difference in the nanoarchitecture of BMOFs under different crystallization pathways that was previously not seen. In addition, we find the nanoarchitecture significantly affects the bioactivity of the BMOFs. This work gives an important insight into the structure-activity relationship of BMOFs synthesized in different scenarios, and may act as a guide to engineer next-generation materials with excellent biological and chemical functions.

Drought disaster space agglomeration assessment is one of the important components of meteorological disaster prevention and mitigation. Agriculture affected by drought disaster is not only a serious threat to world food security, but also an obstacle to sustainable development. Additionally, China is an important agricultural import and export country in the world. Therefore, we used the global Moran’s I and the local indicators of spatial autocorrelation (LISA) to reveal the spatial agglomeration of agricultural drought disaster in China from1978 to 2016, respectively. The results showed that China’s agricultural drought disaster presents local spatial autocorrelation of geographical agglomeration at national level during the study period. The spatial agglomeration regions of China’s agricultural drought disaster were in Inner Mongolia, Jilin province, Heilongjiang province, Liaoning province, Shanxi province, Hebei province, Shandong province, Shaanxi province and Henan province, indicating that agricultural drought disaster mainly distributed in North and Northwest China, especially occurred in the Yellow River Basin and its north areas. We also found that the overall movement direction of agricultural drought disaster agglomeration regions was northwest, and the maximum moving distance was 722.16 km. Our results might provide insight in early warning and prevention for drought disaster.

Quantitatively assessing the impacts of drought on grassland has significant implications to understand the degradation mechanism and prevention degraded grassland. In this study, we analyzed the relationship between grassland drought and grassland Net Primary Productivity (NPP) based on the self-calibrated Palmer Drought Severity Index (scPDSI) from 1982 to 2008. The results showed that the global grassland scPDSI value had a slightly increasing trend with the rate of 0.0119 per year (R2 = 0.195), indicating that the global grassland drought lighter to some extent during study period. Moreover, the correlation coefficient between annual grassland NPP and scPDSI was from −0.83 to 0.92. The grassland NPP decreased under mild drought from 1992 to 1996. Additionally, the correlation coefficient between scPDSI and NPP for each grassland type was: Closed Shrublands > Non-woody grassland > Savannas > Open Shrublands > Woody Savannas, indicating that drought had difference influences on the different grassland types. Our results might provide the underlying insights needed to be guide for the effects of extreme weather events on grassland NPP.

Portable devices featured with fast analysis and affordable methodologies for clinical diagnostics have stimulated the rapid development of point-of-care (POC) technologies, potentially lowering the mortality rate. Herein, we demonstrated a portable, robust, and user-friendly intelligent metal-organic frameworks (MOFs) paper device, called smartphone-assisted biomimetic MOFs nanoreactor colorimetric paper (SBMCP), for on-demand POC detection of endogenous biomolecules. The concept of this paper platform was analogous to the intracellular cascades signal transduction, wherein the single/multiple enzymes components trapped within a ZIF-8 exoskeleton allowed the sensitive and selective recognition of target analyte via the accessible micropores network of ZIF-8, and then transferred the recognition event to a visual color signal based on the cascade reaction. Meanwhile, the ZIF-8 exoskeleton also endowed the enzymes with significantly elevated stability. As a result, this robust and portable SBMCP sensor enabled the on-site analysis of different important disease-related biomolecules through modulating the enzyme cascades, combining with a custom-designed smartphone application for signal readout. In the SBMCP assay, no sophisticated instruments or professional skill of the user was required, only 5 μL sample volume was needed, and the whole analysis process could be achieved within a portable MOFs paper and pervasive smartphone, endowing this new assay with the merits of low-cost, time-saving and easy-to-use. We demonstrated this SBMCP sensor was capable of real-time colorimetric detection of glucose and uric acid in diabetes and gout events. It is believed that this portable biosensor platform proposed herein potentially represents promising alternatives for POC diagnosis, especially applicable in developing world and resource-limited settings.

An agricultural drought disaster was analyzed with the new insight of rescaled statistics (R/S) and wavelet analysis in this study. The results showed that: (1) the Hurst index of the agricultural disaster area, the inundated area of agricultural drought disaster, and the grain loss was 0.821, 0.874, and 0.953, respectively, indicating that the process of the agricultural drought disaster had stronger positive continuity during the study period, (2) based on the Morlet analysis of the agricultural disaster area, the inundated area of the agricultural drought disaster, and the grain loss of China from 1950 to 2016, the time series of the agricultural drought had multiple time scale features with the periodic variation on a large scale containing the periodic variation on a small scale, and (3) in the last 67 years, the strong wavelet energy spectrum of the agricultural disaster area, the inundated area of the agricultural drought disaster, and the grain loss was at the time scale of &asymp, 22&ndash, 32 years, &asymp, 24&ndash, 32 years, and &asymp, 25&ndash, 32 years, respectively. In addition, the first major period in the agricultural drought disaster area, the inundated area of agricultural drought disaster, and the grain loss had average periods of approximately 16 years, 16 years, and 18 years, respectively.

While quantitative assessment of ecosystems degradation is quite addressed in the literature, quantitatively separating the relative contribution of climate variation and human activities to grassland ecosystem degradation is still limited, although well recognized as a key knowledge for a better understanding of the degradation mechanisms and for more efficient control of degradation processes. In this study, actual net primary productivity (ANPP) was selected as an indicator to investigate the grassland dynamics from 2000 to 2013. In addition, potential NPP (PNPP) and human-induced NPP (HNPP), which was calculated as the difference between PNPP and ANPP, were used to differentiate the relative impacts of climate variation and human activities on grassland degradation/restoration, respectively. Results showed that 60.94% of the total global area of grassland experienced restoration over the study period, with an increase in NPP by 1864.81 Tg C across the globe. The restored areas induced by climate variation and human activities accounted for 45.73% and 34.99% with an increases in NPP by 852.75 Tg C and 652.50 Tg C, respectively. By contrast, nearly 39.06% of the global grassland area experienced degradation. This degradation was associated with a noticeable decrease in ANPP by 325.53 Tg C. While 45.45% of the degraded grassland areas were influenced by climate variation, human activities were accounted for around 40.11% of this degradation. The relative effect of the two factors (i.e. climate variation and human activities) on grassland changes was found to vary greatly among the studied six continents. While human activities exerted larger impacts than climate variation on grassland degradation in North America and Europe, climate variation was the dominant factor for grassland restoration in Asia, Europe, Oceania and North America, which can be mainly attributed to the increase in precipitation during the study period. The findings of the current study improved our understanding of the relative impacts of climate variation and human activities on grassland degradation and restoration at the global scale.

Grassland plays a key role in socioeconomic development and environmental protection in Africa. Climate variation and human activities are two main drivers of grassland dynamics. Quantitatively assessing the contributions of these two factors and understanding the driving mechanisms are important in ecosystem adaptation and management. In this research, the spatiotemporal patterns of grassland dynamics in Africa during 2000–2015 were analyzed based on the net primary productivity (NPP), M-K test, linear regression analysis, and correlation analysis. In addition, the potential NPP (PNPP), human-induced NPP (HNPP) and actual NPP (ANPP) were employed to establish scenarios to distinguish the relative impacts of climatic and human factors on grassland dynamics. An overall grassland ANPP increase than decrease (62.91% vs 37.09%) was found during 2000–2015. 21.80% of the total grassland area showed increases in ANPP, which was influenced by climate variation, whereas 23.61% were affected by human activities. The ANPP decreases induced by climate variation, human activities and the combination of these two factors occupied 19.31%, 8.39% and 9.39% of the total grassland area, respectively. Therefore, the contributions of climatic and human factors on ANPP increase were almost consistent, while climate variation was the dominated factor on ANPP decrease. In addition, the respective roles of these two factors were quite different in five grassland types. The dynamics of ANPP in closed shrublands, non-woody grasslands, and open shrublands were mainly attributed to the climate variation. Meanwhile, the human-dominated increases in ANPP were observed in woody savannas. Further analysis demonstrated that the increases in African grassland ANPP are likely due to the mitigation of drought and reduction in land use intensity, while the decreases in ANPP were related to unbalance of local hydrothermal condition and overgrazing. This study expects to improve the understanding of the respective contributions of climatic and human factors on grassland dynamics in Africa.