Clouds cover about 70% of Earth's surface and play a dominant role in the energy and water cycle of our planet. Only satellite observations provide a continuous survey of the state of the atmosphere ...over the entire globe and across the wide range of spatial and temporal scales that compose weather and climate variability. Satellite cloud data records now exceed more than 25 years; however, climate data records must be compiled from different satellite datasets and can exhibit systematic biases. Questions therefore arise as to the accuracy and limitations of the various sensors and retrieval methods. The Global Energy and Water Cycle Experiment (GEWEX) Cloud Assessment, initiated in 2005 by the GEWEX Radiation Panel (GEWEX Data and Assessment Panel since 2011), provides the first coordinated intercomparison of publicly available, standard global cloud products (gridded monthly statistics) retrieved from measurements of multispectral imagers (some with multiangle view and polarization capabilities), IR sounders, and lidar. Cloud properties under study include cloud amount, cloud height (in terms of pressure, temperature, or altitude), cloud thermodynamic phase, and cloud radiative and bulk microphysical properties (optical depth or emissivity, effective particle radius, and water path). Differences in average cloud properties, especially in the amount of high-level clouds, are mostly explained by the inherent instrument measurement capability for detecting and/or identifying optically thin cirrus, especially when overlying low-level clouds. The study of long-term variations with these datasets requires consideration of many factors. The monthly gridded database presented here facilitates further assessments, climate studies, and the evaluation of climate models.
Applications of adenine base editors (ABEs) have been constrained by the limited compatibility of the deoxyadenosine deaminase component with Cas homologs other than SpCas9. We evolved the deaminase ...component of ABE7.10 using phage-assisted non-continuous and continuous evolution (PANCE and PACE), which resulted in ABE8e. ABE8e contains eight additional mutations that increase activity (k
) 590-fold compared with that of ABE7.10. ABE8e offers substantially improved editing efficiencies when paired with a variety of Cas9 or Cas12 homologs. ABE8e is more processive than ABE7.10, which could benefit screening, disruption of regulatory regions and multiplex base editing applications. A modest increase in Cas9-dependent and -independent DNA off-target editing, and in transcriptome-wide RNA off-target editing can be ameliorated by the introduction of an additional mutation in the TadA-8e domain. Finally, we show that ABE8e can efficiently install natural mutations that upregulate fetal hemoglobin expression in the BCL11A enhancer or in the the HBG promoter in human cells, targets that were poorly edited with ABE7.10. ABE8e augments the effectiveness and applicability of adenine base editing.
ABSTRACT
Basic oxygen furnace (BOF) slag and flue gas desulfurization (FGD) residues both are industrial wastes. Research on using BOF slag as a novel aggregate and FGD residues as a filler in road ...construction has benefits both in environment and economics. The main objective of this research was to evaluate the effect of FGD residues and BOF slag on the fatigue performance and moisture resistance of asphalt mixtures. The fatigue performance of asphalt mixture was conducted by means of indirect tensile fatigue test. Stress loading control mode, with four stress levels (300, 400, 500 and 600 kPa), was used in this research. Statistic t‐test was adopted, and it had approved the positive effect of BOF slag and FGD residues on the fatigue lives of asphalt mixture. Moisture resistance of asphalt mixture was investigated by retained Marshall stability test and tensile strength ratio test. Research results indicate that BOF slag and FGD residues can improve the fatigue and moisture resistance, when the BOF slag and FGD residues based asphalt mixture was designed properly.
Transient changes in intracellular Ca(2+) concentration have been well recognized to act as cell signals coupling various environmental stimuli to appropriate physiological responses with accuracy ...and specificity in plants. Calmodulin (CaM) and calmodulin-like proteins (CMLs) are major Ca(2+) sensors, playing critical roles in interpreting encrypted Ca(2+) signals. Ca(2+)-loaded CaM/CMLs interact and regulate a broad spectrum of target proteins such as channels/pumps/antiporters for various ions, transcription factors, protein kinases, protein phosphatases, metabolic enzymes, and proteins with unknown biochemical functions. Many of the target proteins of CaM/CMLs directly or indirectly regulate plant responses to environmental stresses. Basic information about stimulus-induced Ca(2+) signal and overview of Ca(2+) signal perception and transduction are briefly discussed in the beginning of this review. How CaM/CMLs are involved in regulating plant responses to abiotic stresses are emphasized in this review. Exciting progress has been made in the past several years, such as the elucidation of Ca(2+)/CaM-mediated regulation of AtSR1/CAMTA3 and plant responses to chilling and freezing stresses, Ca(2+)/CaM-mediated regulation of CAT3, MAPK8 and MKP1 in homeostasis control of reactive oxygen species signals, discovery of CaM7 as a DNA-binding transcription factor regulating plant response to light signals. However, many key questions in Ca(2+)/CaM-mediated signaling warrant further investigation. Ca(2+)/CaM-mediated regulation of most of the known target proteins is presumed based on their interaction. The downstream targets of CMLs are mostly unknown, and how specificity of Ca(2+) signaling could be realized through the actions of CaM/CMLs and their target proteins is largely unknown. Future breakthroughs in Ca(2+)/CaM-mediated signaling will not only improve our understanding of how plants respond to environmental stresses, but also provide the knowledge base to improve stress-tolerance of crops.
Eight survey cruises in different seasons have been conducted in the Yellow Sea (YS) and East China Sea (ECS) during the period from 2000 to 2008. Suspended sediment concentration (SSC) and ...hydrological data were collected during each cruise. Data analysis showed that total suspended sediment mass was approximately 0.18 × 10
9 tons in the surveyed area during spring and autumn seasons. Highly turbid waters were found in the shallow waters between the Subei coast, the Changjiang estuary and the Zhejiang coast with seasonal variations.
The investigation provided convincing evidence that suspended sediments were transported from the Subei coast and the southern entrance of the Yellow Sea Trough to the central YS. Muddy patches were found at the sea bed when tidal currents were too weak to erode the bottom sediments and water column stratification and eddies provided favorable conditions for trapping the fine-grained suspended sediments.
The investigation indicated that the different front may have different effect on sediment transport during different seasons. The front between the Yellow Sea Cold Water and the coastal water in the Subei coast appeared to trap the high SSC sediments on the shallow water side of the front. During summer, the front along the Zhejiang coast seemed to prevent suspended sediments from transport across the front due to circulation in the front zone and upwelling along the Zhejiang coast. During winter, sediments were likely transported across the front to the central continental shelf of the ECS with the help of the downwelling and lateral Ekman transport driven by monsoon winds.
► We collect abundant in-situ data from 8 cruises during 2000–2008. ► We discuss the seasonal sediment transport and possible mechanism. ► Suspended sediments are transported from the Subei coast to the central Yellow Sea. ► A new explanation is given on the formation of muddy patches in the region. ► The different front may have different effect on sediment transport during different seasons.
Understanding the photoexcited carrier-relaxation actions in ultrasmall black phosphorus quantum dots (BPQDs) will play a crucial role in the fields of electronics and optoelectronics. Herein, we ...report the ultraviolet (UV) saturable absorption and ultrafast photoexcited carrier-relaxation dynamics of BPQDs. The ultrasmall BPQDs are synthesized using a facile liquid-exfoliation method and possess a diameter of 3.8 ± 0.6 nm and a thickness of 1.5 ± 0.4 nm. Femtosecond open-aperture (OA) Z-scan measurements showed typical saturable absorption properties in the UV band. A negative nonlinear optical (NLO) absorption coefficient of -(1.4 ± 0.3) × 10
cm GW
and a saturable intensity of 6.6 ± 1.3 GW cm
were determined. Using a degenerate pump-probe technique, an ultrafast photoexcited carrier-recombination time was observed in the range of 216-305 fs, which was 3 orders of magnitude faster than that of BP nanosheets. Such an ultrafast relaxation component may be attributable to the edge- and step-mediated recombination and was confirmed by our density functional theory (DFT) calculations. This work provides fundamental insight into the underlying mechanism of the photoexcited carrier relaxation dynamic action in BPQDs which can enable UV photonic devices.
Spectral similarity indices were used to select similar soil samples from a spectral library and improve the predictive accuracy of target samples. There are many similarity indices available, and ...precisely how to select the optimum index has become a critical question. Five similarity indices were evaluated: Spectral angle mapper (SAM), Euclidean distance (ED), Mahalanobis distance (MD), SAM_pca and ED_pca in the space of principal components applied to a global soil spectral library. The accordance between spectral and compositional similarity was used to select the optimum index. Then the optimum index was evaluated if it can maintain the greatest predictive accuracy when selecting similar samples from a spectral library for the prediction of a target sample using a partial least squares regression (PLSR) model. The evaluated physiochemical properties were: soil organic carbon, pH, cation exchange capacity (CEC), clay, silt, and sand content. SAM and SAM_pca selected samples were closer in composition compared to the target samples. Based on similar samples selected using these two indices, PLSR models achieved the highest predictive accuracy for all soil properties, save for CEC. This validates the hypothesis that the accordance information between spectral and compositional similarity can help select the appropriate similarity index when selecting similar samples from a spectral library for prediction.
Obesity confers an independent risk for carcinogenesis. In the liver, steatosis often proceeds cancer formation; however, the mechanisms by which steatosis promotes carcinogenesis is unknown. We ...hypothesize that steatosis alters the microenvironment to promote proliferation of tumor initiating cells (TICs) and carcinogenesis. We used several liver cancer models to address the mechanisms underlying the role of obesity in cancer and verified these findings in patient populations. Using bioinformatics analysis and verified by biochemical assays, we identified that hepatosteatosis resulting from either Pten deletion or transgenic expression of HCV core/NS5A proteins, promotes the activation of Wnt/β-catenin. We verified that high fat diet lipid accumulation is also capable of inducing Wnt/β-catenin. Caloric restriction inhibits hepatosteatosis, reduces Wnt/β-catenin activation and blocks the expansion of TICs leading to complete inhibition of tumorigenesis without affecting the phosphatase and tensin homologue deleted on chromosome 10 (PTEN) loss regulated protein kinase B (AKT) activation. Pharmacological inhibition or loss of the Wnt/β-catenin signal represses TIC growth in vitro, and decreases the accumulation of TICs in vivo. In human liver cancers, ontology analysis of gene set enrichment analysis (GSEA)-defined Wnt signature genes indicates that Wnt signaling is significantly induced in tumor samples compared with healthy livers. Indeed, Wnt signature genes predict 90% of tumors in a cohort of 558 patient samples. Selective depletion of macrophages leads to reduction of Wnt and suppresses tumor development, suggesting infiltrating macrophages as a key source for steatosis-induced Wnt expression. These data established Wnt/β-catenin as a novel signal produced by infiltrating macrophages induced by steatosis that promotes growth of tumor progenitor cells, underlying the increased risk of liver tumor development in obese individuals.
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