Geographical urban morphology as a field of research provides a systematic basis for theorizing and managing urban landscape change. After a review of urban morphology as a field of knowledge, ...particularly within Europe, and as a basis for planning and urban design, an example of its application in an urban design studio is discussed, focusing on the urban waterfront redevelopment in Auckland, New Zealand. The characterization of urban landscape forms is supported by cartographic- and field-based investigation. Urban design guidelines and development plans prepared by students contribute to improving the character of the built environment.
Summary
Changes in carbohydrates and organic acids largely determine the palatability of edible tissues of horticulture crops. Elucidating the potential molecular mechanisms involved in the change in ...carbohydrates and organic acids, and their temporal and spatial crosstalk are key steps in understanding fruit developmental processes. Here, we used apple (Malus domestica Borkh.) as research materials and found that MdbHLH3, a basic helix–loop–helix transcription factor (bHLH TF), modulates the accumulation of malate and carbohydrates. Biochemical analyses demonstrated that MdbHLH3 directly binds to the promoter of MdcyMDH that encodes an apple cytosolic NAD‐dependent malate dehydrogenase, activating its transcriptional expression, thereby promoting malate accumulation in apple fruits. Additionally, MdbHLH3 overexpression increased the photosynthetic capacity and carbohydrate levels in apple leaves and also enhanced the carbohydrate accumulation in fruits by adjusting carbohydrate allocation from sources to sinks. Overall, our findings provide new insights into the mechanism of how the bHLH TF MdbHLH3 modulates the fruit quality. It directly regulates the expression of cytosolic malate dehydrogenase MdcyMDH to coordinate carbohydrate allocation and malate accumulation in apple.
Long noncoding RNAs (lncRNAs) have emerged as important components of gene regulatory network in embryonic stem cells (ESCs). However, the function and molecular mechanism of lncRNAs are still ...largely unknown. Here we identifies Trincr1 (TRIM71 interacting long noncoding RNA 1) lncRNA that regulates the FGF/ERK signaling and self-renewal of ESCs. Trincr1 is exported by THOC complex to cytoplasm where it binds and represses TRIM71, leading to the downregulation of SHCBP1 protein. Knocking out Trincr1 leads to the upregulation of phosphorylated ERK and ERK pathway target genes and the decrease of ESC self-renewal, while knocking down Trim71 completely rescues the defects of Trincr1 knockout. Furthermore, ectopic expression of Trincr1 represses FGF/ERK signaling and the self-renewal of neural progenitor cells (NPCs). Together, this study highlights lncRNA as an important player in cell signaling network to coordinate cell fate specification.
Summary
Malic acid accumulation in the vacuole largely determines acidity and perception of sweetness of apple. It has long been observed that reduction in malate level is associated with increase in ...ethylene production during the ripening process of climacteric fruits, but the molecular mechanism linking ethylene to malate reduction is unclear.
Here, we show that ethylene‐modulated WRKY transcription factor 31 (WRKY31)–Ethylene Response Factor 72 (ERF72)–ALUMINUM ACTIVATED MALATE TRANSPORTER 9 (Ma1) network regulates malate accumulation in apple fruit.
ERF72 binds to the promoter of ALMT9, a key tonoplast transporter for malate accumulation of apple, transcriptionally repressing ALMT9 expression in response to ethylene. WRKY31 interacts with ERF72, suppressing its transcriptional inhibition activity on ALMT9. In addition, WRKY31 directly binds to the promoters of ERF72 and ALMT9, transcriptionally repressing and activating ERF72 and ALMT9, respectively. The expression of WRKY31 decreases in response to ethylene, lowering the transcription of ALMT9 directly and via its interactions with ERF72.
These findings reveal that the regulatory complex WRKY31 forms with ERF72 responds to ethylene, linking the ethylene signal to ALMT9 expression in reducing malate transport into the vacuole during fruit ripening.
See also the Commentary on this article by Martinoia & Neuhaus, 239: 821–823.
Summary
Spray‐induced gene silencing (SIGS) is an innovative strategy for crop protection. However, the mechanism of SIGS is not known. Here, we first demonstrate that secondary small interfering RNA ...(siRNA) amplification limits the application of SIGS. A myosin5 gene (Myo5) was chosen as the target of SIGS in an agronomically important pathogen—Fusarium asiaticum. Five segments corresponding to the different regions of the Myo5 gene were found to efficiently silence Myo5, resulting in cell wall defects, life cycle disruption and virulence reduction. Myo5‐8 (one of the Myo5 segments) induced sequence‐specific RNA interference (RNAi) activity in F. asiaticum, F. graminearum, F. tricinctum and F. oxysporum, but not in other fungi, in vitro. Remarkably, the silencing of Myo5 lasted for only 9 h unless the double‐stranded RNA (dsRNA) was continuously supplied, because F. asiaticum is unable to maintain siRNA amplification. After spraying on plants, dsRNAs were more efficiently taken up via the wounded surface. The antifungal activity of dsRNAs taken up by plant cells was higher and longer lasting than that dried onto the plant surface. In contrast with dsRNAs in fungi, dsRNAs in plant cells could efficiently turn into substantial siRNAs via secondary amplification machinery. Our findings provide new implications to develop SIGS as a mainstream disease control strategy against Fusarium and other fungi.
Light-to-heat conversion has been intensively investigated due to the potential applications including photothermal therapy and solar energy harvesting. As a fundamental property of materials, ...accurate measurement of light-to-heat conversion efficiency (LHCE) is of vital importance in developing advanced materials for photothermal applications. Herein, we report a photothermal and electrothermal equivalence (PEE) method to measure the LHCE of solid materials by simulating the laser heating process with electric heating process. The temperature evolution of samples during electric heating process was firstly measured, enabling us to derive the heat dissipation coefficient by performing a linear fitting at thermal equilibrium. The LHCE of samples can be calculated under laser heating with the consideration of heat dissipation coefficient. We further discussed the effectiveness of assumptions by combining the theoretical analysis and experimental measurements, supporting the obtained small error within 5% and excellent reproducibility. This method is versatile to measure the LHCE of inorganic nanocrystals, carbon-based materials and organic materials, indicating the applicability of a variety of materials.
SUMMARY
Drought stress is one of the dominating challenges to the growth and productivity in crop plants. Elucidating the molecular mechanisms of plants responses to drought stress is fundamental to ...improve fruit quality. However, such molecular mechanisms are poorly understood in apple (Malus domestica Borkh.). In this study, we explored that the BTB‐BACK‐TAZ protein, MdBT2, negatively modulates the drought tolerance of apple plantlets. Moreover, we identified a novel Homeodomain‐leucine zipper (HD‐Zip) transcription factor, MdHDZ27, using a yeast two‐hybrid (Y2H) screen with MdBT2 as the bait. Overexpression of MdHDZ27 in apple plantlets, calli, and tomato plantlets enhanced their drought tolerance by promoting the expression of drought tolerance‐related genes responsive to dehydration 29A (MdRD29A) and MdRD29B. Biochemical analyses demonstrated that MdHDZ27 directly binds to and activates the promoters of MdRD29A and MdRD29B. Furthermore, in vitro and in vivo assays indicate that MdBT2 interacts with and ubiquitinates MdHDZ27, via the ubiquitin/26S proteasome pathway. This ubiquitination results in the degradation of MdHDZ27 and weakens the transcriptional activation of MdHDZ27 on MdRD29A and MdRD29B. Finally, a series of transgenic analyses in apple plantlets further clarified the role of the relationship between MdBT2 and MdHDZ27, as well as the effect of their interaction on drought resistance in apple plantlets. Collectively, our findings reveal a novel mechanism by which the MdBT2‐MdHDZ27 regulatory module controls drought tolerance, which is of great significance for enhancing the drought resistance of apple and other plants.
Significance Statement
Collectively, our findings clearly decipher a novel regulatory network for drought tolerance in the apple plant, which centers on the regulatory module MdBT2‐MdHDZ27 and its roles in transcriptional regulation and post‐transcriptional modification, which will be useful for improving the drought tolerances of apple and other economically important plant species.
Improvement of the crack resistance of clayey soils by fiber reinforcement was investigated using initially saturated and fiber-reinforced soil specimens subjected to desiccation. An image-processing ...technique was used to quantitatively describe the effect of fiber addition on the geometrical and morphological characteristics of crack patterns. The results show that the soil desiccation cracking behavior was significantly influenced by fiber inclusion: the crack resistance was significantly improved and the amount of desiccation cracks was significantly reduced by fiber addition. Generally, the surface crack ratio (surface of cracks to total surface), number of clods, average length and width of cracks, and crack network connectivity decreased with increasing fiber content, while the average area of clods, number of nodes per unit area, number of crack segments per unit area, crack density, and specimen integrity increased. During crack propagation, the surface crack ratio increased with decreasing water content and finally reached stabilization. Comparison between the surface crack ratio of the natural soil specimen and that of the fiber-reinforced soil specimen showed that the former was always higher than the latter. The fiber length was found to have an insignificant effect on the soil desiccation cracking behavior.
•Biochar affects the desiccation cracking characteristics of clayey soils by changing the evaporation process.•Biochar weakens the connection between soil particles, but more biochar does not ...necessarily induce more cracks.•Biochar can effectively inhibit the width of desiccation cracks.•4% and 6% biochar in PKE and XS is recognized as the optimal dosage, respectively.
Biochar is a promising material for soil remediation. However, the influence of biochar on soil cracking has not been clearly understood to date. Soil cracking can significantly change the mobility of contaminants in soil and consequently the remediation performance of biochar. This study investigates the effect of a wood biochar on the desiccation shrinkage characteristics of two clayey soils (PKE and XS). The biochar dosages selected are 0%, 0.5%, 2%, 4%, 6%, and 10% (w/w). The results indicate that biochar affects the desiccation cracking characteristics of clayey soils by changing the evaporation process. For PKE, the evaporation rate decreased by 6.56% and 5.59% with 0.5% and 2% biochar addition, respectively, and increased by 2.11% and 17.20% with 4% and 6% biochar addition. Similarly, with the biochar dosage ranges from 0.5% to 10% for XS soil, the evaporation rate decreased by 8.57%, 8.73%, 4.56%, and increased by 0.96% and 41.06%, respectively. Image processing analysis on the cracks indicates that the addition of biochar decreases the quantitative parameters such as the crack ratio, the number of soil mass and the fractal dimension for both treated soils. The crack ratio, the number of cracks and the number of soil mass were reduced by 16.85%, 32.26% and 39.22% for 4% biochar addition in PKE. The value of XS soil with 6% biochar addition decreased by 30.80%, 8.28%, and 11.61%, respectively. Furthermore, biochar can effectively reduce the width of cracks. The role of biochar in the development of desiccation cracking may include (1) occupying the shrinkage space of soil particles; (2) weakening the bonding between soil particles and (3) providing hydrophobic channels. In general, the application of 4% and 6% biochar in PKE and XS respectively has the best performance in inhibiting soil cracking.
Vertical deformation can be revealed by various techniques such as precise leveling, satellite imagery, and extensometry. Despite considerable effort, recording detailed subsurface deformation using ...traditional extensometers remains challenging when attempting to detect localized deformation. Here we introduce distributed fiber optic sensing based on Brillouin scattering as a geophysical exploration method for imaging distributed profiles of vertical deformation. By examining fiber optic cable‐soil interaction we found a threshold in confining pressure to achieve a strong cable‐soil coupling, thus validating data collected from a borehole‐embedded fiber optic cable deployed in Shengze, southern Yangtze Delta, China. Clear‐cut strain profiles acquired from November 2014 to December 2016 allowed us to pinpoint where compaction or rebound was actively occurring and examine strain responses at various locations along the entire cable length. We suggest that distributed fiber optic sensing can complement with extensometry and remote sensing techniques for improved monitoring of vertical deformation.
Plain Language Summary
Recording detailed subsurface deformation using traditional methods (e.g., extensometers) is sometimes difficult due to limited measuring points. This dilemma may be overcome by using the emerging distributed fiber optic sensing technology, which transforms common telecommunication fiber optic cables into sensors capable of making distributed strain measurements. We report the use of this technology for monitoring distributions of vertical deformation resulting from groundwater ion in Shengze, southern Yangtze Delta, China. An evaluation of the performance of a borehole‐embedded fiber optic cable helps us to validate the in situ strain data. The advantage of using this technology for vertical deformation sensing is the ability to locate any strata undergoing compaction or rebound and look at strain responses at any depth of interest. Moreover, recording subsurface changes in this fashion may also be useful in other geophysical and engineering applications that require refined monitoring of the media.
Key Points
Distributed fiber optic sensing with Brillouin scattering provides a clear subsurface strain profile using a single fiber optic cable
We find a threshold in confining pressure to achieve a strong fiber optic cable‐soil coupling
Distributed fiber optic sensing can complement with existing techniques for improved monitoring of vertical deformation
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