SUMMARY
Seed number and harvesting ability in maize (Zea mays L.) are primarily determined by the architecture of female inflorescence, namely the ear. Therefore, ear morphogenesis contributes to ...grain yield and as such is one of the key target traits during maize breeding. However, the molecular networks of this highly dynamic and complex grain‐bearing inflorescence remain largely unclear. As a first step toward characterizing these networks, we performed a high‐spatio‐temporal‐resolution investigation of transcriptomes using 130 ear samples collected from developing ears with length from 0.1 mm to 19.0 cm. Comparisons of these mRNA populations indicated that these spatio‐temporal transcriptomes were clearly separated into four distinct stages stages I, II, III, and IV. A total of 23 793 genes including 1513 transcription factors (TFs) were identified in the investigated developing ears. During the stage I of ear morphogenesis, 425 genes were predicted to be involved in a co‐expression network established by eight hub TFs. Moreover, 9714 ear‐specific genes were identified in the seven kinds of meristems. Additionally, 527 genes including 59 TFs were identified as especially expressed in ear and displayed high temporal specificity. These results provide a high‐resolution atlas of gene activity during ear development and help to unravel the regulatory modules associated with the differentiation of the ear in maize.
Significance Statement
This article will provide a full transcriptional landscape of maize ear during its whole development period.
Neuroscience is a technology‐driven discipline and brain energy metabolism is no exception. Once satisfied with mapping metabolic pathways at organ level, we are now looking to learn what it is ...exactly that metabolic enzymes and transporters do and when, where do they reside, how are they regulated, and how do they relate to the specific functions of neurons, glial cells, and their subcellular domains and organelles, in different areas of the brain. Moreover, we aim to quantify the fluxes of metabolites within and between cells. Energy metabolism is not just a necessity for proper cell function and viability but plays specific roles in higher brain functions such as memory processing and behavior, whose mechanisms need to be understood at all hierarchical levels, from isolated proteins to whole subjects, in both health and disease. To this aim, the field takes advantage of diverse disciplines including anatomy, histology, physiology, biochemistry, bioenergetics, cellular biology, molecular biology, developmental biology, neurology, and mathematical modeling. This article presents a well‐referenced synopsis of the technical side of brain energy metabolism research. Detail and jargon are avoided whenever possible and emphasis is given to comparative strengths, limitations, and weaknesses, information that is often not available in regular articles.
Main Points
Brain energy metabolism is organized hierarchically.
Different organizational levels require different technical approaches.
Technical strengths and weaknesses are made explicit.
Femtosecond-laser ablation is becoming increasingly popular due to its advantageous characteristics such as reduced fractionation and improved lateral resolution. However, since the emission from the ...resulting laser-induced plasmas is reduced and relatively short-lived, optical spectroscopy analyses with fs lasers (LIBS) are often carried out with enhancement strategies, such as double-pulse LIBS. For orthogonal double pulse set ups, characterizing the spatio-temporal excitation of the fs-LIP can be useful to fully optimize the scheme. This work aims to characterize the structure of a fs-laser induced plasma in atmospheric pressure, illustrating the general behavior of the plasma plume for different target materials (metals and dielectrics), and further obtain insight about the emission and excitation characteristics of the plume for pure copper and PVC samples. The results show a clear two-component structure of the metallic plumes, composed by a fast-displacing upper component that presents higher excitation and higher ionization degree and a slow, almost static component that remains near the sample surface throughout the complete evolution. On the contrary, PVC presented only one fast-displacing component which was seen not to be homogeneous in terms of excitation. As a general feature, in the present study conditions, all the plasma plumes induced in different samples presented an intensity-dominating fast component, with discrepancies in the presence and relative intensity of the slow component.
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•Characterization of fs-laser induced plasma plume behavior on different matrices.•General two-component structure for metals, with brighter fast component.•Study of excitation conditions in each component of a metallic (Cu) plasma plume.•Excitation and spatio-temporal distribution of species in a dielectric (PVC) plume.
The air quality in urban areas is a major concern in modern cities due to significant impacts of air pollution on public health, global environment, and worldwide economy. Recent studies reveal the ...importance of micro-level pollution information, including human personal exposure and acute exposure to air pollutants. A real-time system with high spatio-temporal resolution is essential because of the limited data availability and non-scalability of conventional air pollution monitoring systems. Currently, researchers focus on the concept of The Next Generation Air Pollution Monitoring System (TNGAPMS) and have achieved significant breakthroughs by utilizing the advance sensing technologies, MicroElectroMechanical Systems (MEMS) and Wireless Sensor Network (WSN). However, there exist potential problems of these newly proposed systems, namely the lack of 3D data acquisition ability and the flexibility of the sensor network. In this paper, we classify the existing works into three categories as Static Sensor Network (SSN), Community Sensor Network (CSN) and Vehicle Sensor Network (VSN) based on the carriers of the sensors. Comprehensive reviews and comparisons among these three types of sensor networks were also performed. Last but not least, we discuss the limitations of the existing works and conclude the objectives that we want to achieve in future systems.
Existing, high‐fidelity models for sewer network modeling are accurate but too slow and inflexible for modern applications such as optimization or scenario analysis. Reduced complexity surrogate ...modeling has been applied in response to this, however, current approaches are expensive to set up and still require high‐fidelity simulations to derive parameters. In this study, we compare and develop graph partitioning algorithms to automatically group sections of sewer networks into semi‐distributed compartments. These compartments can then be simulated using sewer network information only in the integrated modeling framework, CityWat‐SemiDistributed (CWSD), which has been developed for application to sewer network modeling in this study. We find that combining graph partitioning with CWSD can produce accurate simulations 100–1,000× faster than existing high‐fidelity modeling. Because we anticipate that many CWSD users will not have high‐fidelity models available, we demonstrate that the approach provides reasonable simulations even under significant parametric uncertainty through a sensitivity analysis. We compare multiple graph partitioning techniques enabling users to specify the spatial aggregation of the partitioned network, also enabling them to preserve key locations for simulation. We test the impact of temporal resolution, finding that accurate simulations can be produced with timesteps up to one hour. Our experiments show a log‐log relationship between temporal/spatial resolution and simulation time, enabling users to pre‐specify the efficiency and accuracy needed for their applications. We expect that the efficiency and flexibility of our approach may facilitate novel applications of sewer network models ranging from continuous simulations for long‐term planning to spatially optimizing the placement of network sensors.
Plain Language Summary
Existing sewer models are too slow and inflexible to be applied to a range of modern demands that are placed on sewer modeling. For example, climate analyses require simulations of long and continuous timeseries spanning decades over a range of potential futures. The solution to this is to reduce the complexity of sewer models, aiming to provide good enough simulations that are computationally fast and flexible to adapt to the variety of planning situations faced by modern sewer model users. Existing approaches to reduced complexity sewer modeling require time consuming activities such as calibrating to detailed simulations (which are often not available) and inflexible methods to reduce complexity (typically aggregating the network spatially). In this paper, we provide a physically based reduced complexity model that can be applied without calibration. We combine it with graph partitioning, which is a flexible and automated way to reduce a sewer network's complexity in space. Our simulation experiments find the proposed approach to be successful in producing accurate simulations and highlight the utility of reduced complexity modeling by investigating how spatial and temporal resolution interact and impact the accuracy of simulation results.
Key Points
Automatic graph partitioning can flexibly reduce the complexity of sewer networks to enable surrogate modeling
CityWat‐SemiDistributed can model these reduced networks without needing parameter derivation from high‐fidelity simulations
The combined approach provides computationally cheap simulations and performs accurately even when no high‐fidelity model is available
Black carbon (BC) exposure in China continues to be relatively high, prompting researchers to assess BC exposure levels using data from monitoring sites, satellite remote sensing, and models. ...However, data regarding the application of a combined strategy comprising the analysis of monitoring data and various types of data to simulate BC exposure levels are lacking. Hence, the current study seeks to estimate short- and long-term BC exposure levels by combining national monitoring data with data from the second Modern-Era Retrospective analysis for Research and Applications (MERRA-2). Furthermore, this study attempts to improve the spatio-temporal resolution of BC exposure levels using Bayesian maximum entropy (BME). The BME model performed well in terms of estimating short- (R2 = 0.74 and RMSE = 1.76 μg/m3) and long-term (R2 = 0.76 and RMSE = 1.3 μg/m3) exposure. Premature mortalities and economic losses were also assessed by applying localised concentration–response coefficients simulated in China. A total of 74,500 (95% confidence interval (CI): 23,900–124,500) and 538,400 (95% CI: 495,000–581,300) all-cause premature mortality cases were found to be associated with short- and long-term BC exposure, respectively. Meanwhile, short-term BC exposure was associated with economic losses ranging from 7.5 to 13.2 billion US dollars (USD) (1 USD = 6.36 RMB on January 19, 2022) based on amended human capital (AHC) and willingness to pay (WTP), accounting for 0.06%–0.1% of China's total gross domestic product (GDP) in 2017 (1.2 × 104 billion USD), respectively. The economic losses for long-term exposure varied from 53 to 93.2 billion USD based on AHC and WTP, accounting for 0.4%–0.8% of China's total GDP in 2017, respectively.
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•Modelled black carbon (BC) exposure level was the highest in Sichuan Basin, China.•All-cause premature mortalities due to long-term BC exposure were 538,400 cases in 2017.•Economic losses due to BC exposure accounted for 0.8% of the 2017 GDP of China.
Spatially resolved environmental models are important tools to introduce and highlight the spatial variability of the real world into modeling. Although various spatial models have been developed so ...far, yet the development and evaluation of these models remain a challenging task due to several difficulties related to model setup, computational cost, and obtaining high-resolution input data (e.g., monitoring and emission data). For example, atmospheric transport models can be used when high resolution predicted concentrations in atmospheric compartments are required, while spatial multimedia fate models may be preferred for regulatory risk assessment, life cycle impact assessment of chemicals, or when the partitioning of chemical substances in a multimedia environment is considered. The goal of this paper is to review and compare different spatially resolved environmental models, according to their spatial, temporal and chemical domains, with a closer insight into spatial multimedia fate models, to achieve a better understanding of their strengths and limitations. This review also points out several requirements for further improvement of existing models as well as for their integration.
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•Spatial atmospheric transport models and multimedia fate models were reviewed.•More than 50 spatial models were described including their applications.•Their spatial, temporal, and chemical domains were investigated for comparison.•Further developments especially their integration is suggested.
•Environmental Response Function (ERF) maps surface-atmosphere exchanges.•ERF is capable of upscaling tower eddy covariance observations to regional scale.•The regional flux maps de-bias the ...footprint variation in tower observations.•ERF provides unprecedented spatio-temporal attribution and resolution.
Eddy-covariance measurements are widely used to develop and test parameterizations of land-atmosphere interactions in earth system models. However, a fundamental challenge for model-data comparisons lies in the scale mismatch between the eddy-covariance observations with small (10−1–101km2) and temporally varying flux footprint, and the continuous regional-scale (102–104km2) gridded predictions made in simulations. Here, a new approach was developed to project turbulent flux maps at regional scale and hourly temporal resolution using environmental response functions (ERFs). This is based on an approach employed in airborne flux observations, and relates turbulent flux observations to meteorological forcings and surface properties across the flux footprint. In this study, the fluxes of sensible heat, latent heat and CO2 integrated over a 20×20 km2 target domain differed substantially from the tower observations in their expected value (+27%, −9%, and −17%) and spatio-temporal variation (−22%, −21%, and −3%, repsectively) ERF systematic uncertainties are bound within −11%, −1.5% and +16%, respectively, indicating that tower location bias might be even more pronounced for heat and CO2 fluxes than currently detectable. The ERF-projected fluxes showed general agreement with independent observations at a nearby tower location. Lastly, advantages and limitations of ERF compared to other scaling approaches are discussed, and pathways for improving model-data synthesis utilizing the ERF scaling method are pointed out.
During the coldest periods of the Pleistocene, parts of the Iberian Peninsula were favorable to the establishment of forest refuges. It is therefore essential to characterize them and study their ...evolution, in order to gain a better understanding of the territories occupied by prehistoric societies during these same periods. In this article, we propose to revisit the regional study of environmental changes in eastern Spain around the LGM, through the analysis of the isotopic signal (δ13C) of Solutrean charcoal from Abrigo de la Boja and Cova de les Cendres (ca. 24,500–19,500 cal. BP). The first application of this approach to the Iberian Pleistocene will not only allow us (i) to clarify environmental changes at the two sites and their synchronicity with the North Atlantic influences of this period, but also (ii) to discuss the presence of more or less marked forest refuges in relation to the evolution of regional climatic contrasts.
•New resolution on the environmental signal from the LGM on the Iberian Peninsula.•Adaptability of the isotopic approach (δ13C) to the type of anthracological deposit.•Synchronous comparison of charcoal isotope signals on a regional scale.•Relationship between forest refugia and climatic and Mediterranean influences.•Ongoing reflection on the evolution of regional contrasts in the Mediterranean.
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