Physiological and Transcriptome Analysis Illuminates the Molecular Mechanisms of the Drought Resistance Improved by Alginate Oligosaccharides in Triticum aestivum L.

Alginate oligosaccharides(AOS)enhance drought resistance in wheat(Triticum aestivum L.),but the definite mechanisms remain largely unknown.The physiological and transcriptome responses of wheat seedlings treated with AOS were analyzed under drought stress simulated with polyethylene glycol-6000.The results showed that AOS promoted the growth of wheat seedlings and reduced oxidative damage by improving peroxidase and superoxide dismutase activities under drought stress.A total of 10,064 and 15,208 differentially expressed unigenes(DEGs)obtained from the AOS treatment and control samples at 24 and 72 h after dehydration,respectively,were mainly enriched in the biosynthesis of secondary metabolites(phenylpropanoid biosynthesis,flavonoid biosynthesis),carbohydrate metabolism(starch and sucrose metabolism,carbon fixation in photosynthetic organisms),lipid metabolism(fatty acid elongation,biosynthesis of unsaturated fatty acids,alpha-linolenic acid metabolism,cutin,suberine and wax biosynthesis),and signaling transduction pathways.The up-regulated genes were related to,for example,chlorophyll a-b binding protein,amylosynthease,phosphotransferase,peroxidase,phenylalanine ammonia lyase,flavone synthase,glutathione synthetase.Signaling molecules(including MAPK,plant hormones,H_(2)O_(2) and calcium)and transcription factors(mainly including NAC,MYB,MYB-related,WRKY,bZIP family members)were involved in the AOS-induced wheat drought resistance.The results obtained in this study help underpin the mechanisms of wheat drought resistance improved by AOS,and provides a theoretical basis for the application of AOS as an environmentally sustainable biological method to improve drought resistance in agriculture.

Advances in Quantifying Impact and Extent of Water-Land-Food Nexus for Food Security in Africa

Food systems have the potential to promote human health and enhance environmental sustainability;yet most African countries have decadal starvation and malnourishment due to unstable food systems lacking basic nutritional profiles. To understand the key questions of the African food production and food security crisis, it is important to evaluate the past and the present balance of food production and consumption quantitatively and comprehensively and identify resource constraints. This continental study analyzed water-land-food (WLF) nexus in recent decades (1997-2017) and accessed whether these resources cope with different population growth projections, dietary changes and agricultural water management. The findings revealed that in 2017, total production in Africa for the four major crops was 83.3, 34.1, 21.0 and 26.7 million tons for, respectively, maize, rice, sorghum and wheat. Together with the imported food, 38 countries experienced an increase in kcal by food supply, while 7 countries encountered a decrease. However, only 6 countries were above the 1500 kcal∙capita−1∙day−1—the global average food consumption from the four major crops. The study also found that in the context of food production and out of the total African population, 268 million (21.6%) have enough land and water, 310 million (25.0%) is without enough land and water, further 279 million (22.5%) have enough water but not enough land, and 381 million (30.8%) encounter enough land but not enough water. This is the first WLF nexus study for the African continent and emphasizes the need for efficient and rapid changes in the food systems of the African population, both in production and consumption, in order to provide sustainable and secure food systems, and ultimately approach the first three Sustainable Development Goals.

Different sources of MSCs on pulmonary fibrosis in C57BL/6 mice

Since stem cell therapy is the most effective treatment in the field of tissue reparation and reconstitution,the present study aimed to explore the different sources of mesenchymal stem cells(MSCs)on the different effects of pulmonary fibrosis-related cytokines in C57BL/6 mice.For reaching this goal,we isolated MSCs from umbilical cord blood and placenta and used for stem cell therapy in a mouse model of pulmonary fibrosis model.The pulmonary fibrosis model was done by injecting bleomycin into the trachea of C57BL/6 mice.Then we assessed the degree of pulmonary fibrosis in each mouse lung tissue at weeks 1,2,3,and 4.In addition,flow cytometry was used to evaluate the frequency of CD73,CD90,CD106,CD34,CD45,CD14 cells at the mononuclear cell level;and western blotting assays revealed the expression of IκB-α.Our results showed that stem cell therapy by placenta-derived MSC had a lower level of CD34,CD45,CD14 cells at the mononuclear cell level,and that improved pulmonary fibrosis at both molecular and pathological levels.In addition,western blotting assays revealed that the expression of IκB-αwas down-regulated in MSC-treated animals.In addition,placenta-derived MSC was the most effective in improving pulmonary fibrosis in comparison to other sources.This study suggests that MSC might be a novel therapeutic approach in pulmonary fibrosis due to an enhanced anti-inflammatory effect.Also,MSC modification by gene editing could enhance their therapeutic effect in mouse pulmonary fibrosis.

A Ge-Graded SiGe HBT with β >100 and f_T= 67 GHz

By using reduced pressure chemical vapor deposition (RPCVD), the high strained, Ge-graded SiGe film growth has been realized. The film was used as a base of the HBT (Heterojunction Bipolar Transistor) developed in 0.35 μm SiGe BiCMOS process technology, and made the device give good DC characteristics (β > 100) and high-frequency performance (fT = 67 GHz), thus meeting the requirements for technical specifications in 0.35 μm SiGe BiCMOS process technology.

Preparation of panda-shaped photonic crystal fibers with and without silver wire

A method of preparing panda-shaped photonic crystal fibers(PCFs)based on secondary drawing technology is proposed in this paper.The secondary drawing can not only reduce fiber diameter but also reduce core size by adding a glass sleeve.Silver-filled and non-silver-filled panda PCFs are prepared.The two ends of silver-filled panda PCF are connected with a broadband light source and a spectrometer,respectively,and the surface plasmon resonance phenomenon is detected.The secondary drawing technology provides a meaningful reference for the preparation of PCF in the future,and the prepared silver-filled panda PCF can be prepared into an optical fiber filter.

Novel seven-membered ring-fused naphthalimide derivatives with potentials for cancer theranostics

Naphthalimide derivatives have good planarity and large conjugated structure and therefore possess photophysical properties and biological activities. Previously, our group discovered seven-membered heterocyclic derivatives via modifying 4-and 5-positions of naphthalimide skeleton and found the derivatives had good water solubility and showed large stokes shift and strong fluorescence in water. In this article, we designed and synthesized more seven-membered ring-fused naphthalimide derivatives(Y1-Y16)by introducing different substitutions on the imide group. Among them, Y1, Y5, Y9 were found to show similar cytotoxic activities with Amonafide against A549 and HL60 cells, with IC50values at 10^(-6)mol/L.What is more, the asymmetry derivatives(Y1 and Y5) showed high fluorescent quantum yields in the aqueous phase(Ф = 0.47). Considering the great fluorescence quantum yields in water and the potent anti-tumor activities of the representative seven-membered ring-fused naphthalimides, they have potentials to be used as agents for cancer theranostics.

Shifting from homogeneous to heterogeneous surfaces in estimating terrestrial evapotranspiration: Review and perspectives

Terrestrial evapotranspiration(ET)is a crucial link between Earth’s water cycle and the surface energy budget.Accurate measurement and estimation remain a major challenge in geophysical,biological,and environmental studies.Pioneering work,represented by Dalton and Penman,and the development of theories and experiments on turbulent exchange in the atmospheric boundary layer(ABL),laid the foundation for mainstream methodologies in ET estimation.Since the 1990s,eddy covariance(EC)systems and satellite remote sensing have been widely applied from cold to tropical and from arid to humid regions.They cover water surfaces,wetlands,forests,croplands,grasslands,barelands,and urban areas,offering an exceptional number of reports on diverse ET processes.Surface nocturnal ET,hysteresis between ET and environmental forces,turbulence intermittency,island effects on heterogeneous surfaces,and phase transition between underlying surfaces are examples of reported new phenomena,posing theoretical and practical challenges to mainstream ET methodologies.Additionally,based on non-conventional theories,new methods have emerged,such as maximum entropy production and nonparametric approaches.Furthermore,high-frequency on-site observation and aerospace remote sensing technology in combination form multi-scale observations across plant stomata,leaves,plants,canopies,landscapes,and basins.This promotes an insightful understanding of diverse ET processes and synthesizes the common mechanisms of the processes between and across spatial and temporal scales.All the recent achievements in conception,model,and technology serve as the basis for breaking through the known difficulties in ET estimation.We expect that they will provide a rigorous,reliable scientific basis and experimental support to address theoretical arguments of global significance,such as the water-heat-carbon cycle,and solve practical needs of national importance,including agricultural irrigation and food security,precise management of water resources and eco-environmental protection,and regulation of the urban thermal environment and climate change adaptation.