3D GIS Modelling of Road and Building Material Stocks: A Case Study of Grenada

Recent years have witnessed significant material stock accumulation within built environments, resulting in substantial environmental issues, such as greenhouse gas emissions, toxic or harmful wastes, resource scarcity, and land use conflicts. Quantitative analysis of in-use material stocks is important for assessing resource appropriation, improving the socio-economic metabolism model, and enhancing adaptive capacity to climate change. This research presents a bottom-up GIS spatial approach for modelling in-use road and building material stocks in Grenada, a small island state. LiDAR data were applied to the estimation of building heights and building stocks to improve current material stock accounting approaches. A 3D web-based application was developed to visualize material stocks in 3D building models and to enhance the understanding of the spatial distribution of material stocks. In addition, a comparative review was conducted to compare the methodological approach, results, and conclusions of this study with previous material stock studies in Grenada. Results of this study indicate that in 2015, 4,375 kilo tonnes (40.96 t/capita) of materials were stocked within Grenada road networks, which were about one-third of that accumulated in buildings and accounted for a large share (24%) of total material stocks. Aggregates stocked within road networks occupied the largest proportion of stocks, contributing to 55% of total aggregate stocks. The considerable amount of road stocks supports the important role of materials stocked in non-building infrastructure in the context of small island states. A large proportion of road stocks were accumulated in the low-lying coastal areas, which are highly vulnerable to sea level rise. It is predicted that a sea level rise of 2.0 m would cause the majority of road stocks (over 18,187 tonnes) along the coastline of St. George’s Harbour to be inundated. In terms of building material stocks, this study combined GIS footprint data with LiDAR elevation data to obtain the building height for each building, finding that compared with height assumptions based on occupancy classes, LiDAR-derived height estimates were closer to ground truth heights and could better represent the heterogeneity among buildings. The study for the sample site of Grenada (St. George’s) demonstrates that using the inaccurate class-based height assumptions resulted in about 4.8% of overestimation in building stock estimates compared to using LiDAR-derived heights. The most discrepancy was found in concrete since concrete is the main material used in building construction. 3D building models in CityGML format and a 3D WebGIS application built on top of ArcGIS API for JavaScript were developed for Grenada integrating material stocks with the 3D city model. These 3D products can provide policy makers and practitioners with a new perspective and additional insights into material stocks and enable the public to access proprietary GIS data and material stock information through a user-friendly interface. This research serves as a pilot for assessing a novel methodology for estimating building and non-building material stocks in the context of small island states. The methodological approaches and results detailed in this research can further aid small island states in better assessing resource appropriation and evaluating their adaptive capacity to climate change

Controlled manipulation of oxygen vacancies using nanoscale flexoelectricity

Oxygen vacancies, especially their distribution, are directly coupled to the electromagnetic properties of oxides and related emergent functionalities that have implication in device applications. Here using a homoepitaxial strontium titanate thin film, we demonstrate a controlled manipulation of the oxygen vacancy distribution using the mechanical force from a scanning probe microscope tip. By combining Kelvin probe force microscopy imaging and phase-field simulations, we show that oxygen vacancies can move under a stress-gradient-induced depolarisation field. When tailored, this nanoscale flexoelectric effect enables a controlled spatial modulation. In motion, the scanning probe tip thereby deterministically reconfigures the spatial distribution of vacancies. The ability to locally manipulate oxygen vacancies on-demand provides a tool for the exploration of mesoscale quantum phenomena, and engineering multifunctional oxide devices.Comment: 35 pages, Main text and the supplementary information combine

OsLRR-RLK1, an early responsive leucine-rich repeat receptor-like kinase, initiates rice defense responses against a chewing herbivore

Plants are constantly exposed to a variety of environmental stresses, including herbivory. How plants perceive herbivores on a molecular level is poorly understood. Leucine‐rich repeat receptor‐like kinases (LRR‐RLKs), the largest subfamily of RLKs, are essential for plants to detect external stress signals, and may therefore also be involved in herbivore perception. Here, we employed RNA interference silencing, phytohormone profiling and complementation, as well as herbivore resistance assays, to investigate the requirement of an LRR‐RLK for the initiation of rice (Oryza sativa) defenses against the chewing herbivore striped stem borer (SSB) Chilo suppressalis. We discovered a plasma membrane‐localized LRR‐RLK, OsLRR‐RLK1, whose transcription is strongly up‐regulated by SSB attack and treatment with oral secretions of Spodoptera frugiperda. OsLRR‐RLK1 acts upstream of mitogen‐activated protein kinase (MPK) cascades, and positively regulates defense‐related MPKs and WRKY transcription factors. Moreover, OsLRR‐RLK1 is a positive regulator of SSB‐elicited, but not wound‐elicited, levels of jasmonic acid and ethylene, trypsin protease inhibitor activity and plant resistance towards SSB. OsLRR‐RLK1 therefore plays an important role in herbivory‐induced defenses of rice. Given the well‐documented role of LRR‐RLKs in the perception of stress‐related molecules, we speculate that OsLRR‐RLK1 may be involved in the perception of herbivory‐associated molecular patterns

CP-BCS: Binary Code Summarization Guided by Control Flow Graph and Pseudo Code

Automatically generating function summaries for binaries is an extremely valuable but challenging task, since it involves translating the execution behavior and semantics of the low-level language (assembly code) into human-readable natural language. However, most current works on understanding assembly code are oriented towards generating function names, which involve numerous abbreviations that make them still confusing. To bridge this gap, we focus on generating complete summaries for binary functions, especially for stripped binary (no symbol table and debug information in reality). To fully exploit the semantics of assembly code, we present a control flow graph and pseudo code guided binary code summarization framework called CP-BCS. CP-BCS utilizes a bidirectional instruction-level control flow graph and pseudo code that incorporates expert knowledge to learn the comprehensive binary function execution behavior and logic semantics. We evaluate CP-BCS on 3 different binary optimization levels (O1, O2, and O3) for 3 different computer architectures (X86, X64, and ARM). The evaluation results demonstrate CP-BCS is superior and significantly improves the efficiency of reverse engineering.Comment: EMNLP 2023 Main Conferenc

Ru doping induced spin frustration and enhancement of the room-temperature anomalous Hall effect in La2/3Sr1/3MnO3 films

In transition-metal-oxide heterostructures, the anomalous Hall effect (AHE) is a powerful tool for detecting the magnetic state and revealing intriguing interfacial magnetic orderings. However, achieving a larger AHE at room temperature in oxide heterostructures is still challenging due to the dilemma of mutually strong spin-orbit coupling and magnetic exchange interactions. Here, we exploit the Ru doping-enhanced AHE in LSMRO epitaxial films. As the B-site Ru doping level increases up to 20 percent, the anomalous Hall resistivity at room temperature can be enhanced from nOhmcm to uOhmcm scale. Ru doping leads to strong competition between ferromagnetic double-exchange interaction and antiferromagnetic super-exchange interaction. The resultant spin frustration and spin-glass state facilitate a strong skew-scattering process, thus significantly enhancing the extrinsic AHE. Our findings could pave a feasible approach for boosting the controllability and reliability of oxide-based spintronic devices

An herbivore-induced plant volatile reduces parasitoid attraction by changing the smell of caterpillars

Herbivore-induced plant volatiles (HIPVs) can mediate tritrophic interactions by attracting natural enemies of insect herbivores such as predators and parasitoids. Whether HIPVs can also mediate tritrophic interactions by influencing the attractiveness of the herbivores themselves remains unknown. We explored this question by studying the role of indole, a common HIPV in the plant kingdom. We found that herbivory-induced indole increases the recruitment of the solitary endoparasitoid Microplitis rufiventris to maize plants that are induced by Spodoptera littoralis caterpillars. Surprisingly, however, indole reduces parasitoid recruitment when the caterpillars themselves are present on the plants. Further experiments revealed that indole exposure renders S. littoralis caterpillars unattractive to M. rufiventris, leading to an overall reduction in attractiveness of plant-herbivore complexes. Furthermore, indole increases S. littoralis resistance and decreases M. rufiventris parasitization success. S. littoralis caterpillars are repelled by indole in the absence of M. rufiventris but specifically stop avoiding the volatile in the presence of the parasitoid. Our study shows how an HIPV can undermine tritrophic interactions by reducing the suitability and attractiveness of caterpillars to parasitoids

Super-tetragonal Sr4Al2O7: a versatile sacrificial layer for high-integrity freestanding oxide membranes

Releasing the epitaxial oxide heterostructures from substrate constraints leads to the emergence of various correlated electronic phases and paves the way for integrations with advanced semiconductor technologies. Identifying a suitable water-soluble sacrificial layer, compatible with the high-quality epitaxial growth of oxide heterostructures, is currently the key to the development of large-scale freestanding oxide membranes. In this study, we unveil the super-tetragonal Sr4Al2O7 (SAOT) as a promising water-soluble sacrificial layer. The distinct low-symmetric crystal structure of SAOT enables a superior capability to sustain epitaxial strain, thus allowing for broad tunability in lattice constants. The resultant structural coherency and defect-free interface in perovskite ABO3/SAOT heterostructures effectively restrain crack formations during the water-assisted release of freestanding oxide membranes. For a variety of non-ferroelectric oxide membranes, the crack-free areas can span up to a few millimeters in length scale. These compelling features, combined with the inherent high-water solubility, make SAOT a versatile and feasible sacrificial layer for producing high-quality freestanding oxide membranes, thereby boosting their potential for innovative oxide electronics and flexible device designs.Comment: 5 figures and SI, it is the second version of this manuscrip

Data from: Integration of two herbivore-induced plant volatiles results in synergistic effects on plant defense and resistance

Plants can use induced volatiles to detect herbivore‐ and pathogen‐attacked neighbors and prime their defenses. Several individual volatile priming cues have been identified, but whether plants are able to integrate multiple cues from stress‐related volatile blends remains poorly understood. Here, we investigated how maize plants respond to two herbivore‐induced volatile priming cues with complementary information content, the green leaf volatile (Z)‐3‐hexenyl acetate (HAC) and the aromatic volatile indole. In the absence of herbivory, HAC directly induced defense gene expression, while indole had no effect. Upon induction by simulated herbivory, both volatiles increased jasmonate signaling, defense gene expression and defensive secondary metabolite production and increased plant resistance. Defenses and resistance in dual‐volatile exposed plants were more strongly induced than in plants exposed to single volatiles. Induced defense levels in dual volatile‐exposed plants were significantly higher than predicted from the added effects of the individual volatiles, with the exception of induced plant volatile production, which showed no increase upon dual‐exposure relative to single exposure. Thus, plants can integrate different volatile cues into strong and specific responses that promote herbivore defense induction and resistance. Integrating multiple volatiles may be beneficial, as volatile blends are more reliable indicators of future stress than single cues

Understanding the “Holiday Effect” in Online Restaurant Ratings

Plenty of studies have demonstrated the holiday effect in human decision-makings. However, extant research fails to explore whether and how a holiday effect exists in online word-of-mouth generation. This work utilizes online restaurant reviews obtained from the most popular review platform in China to investigate this question with multiple empirical tests. The results suggest that diners are more likely to give a lower online rating on holidays, and this relationship is driven by a combination of restaurants’ specific reasons and diners’ specific factors. Specifically, the level of crowdedness and the quality of the restaurant can partly explain this relationship. Moreover, reviewers are found to be driven by cognitive mental processes instead of being carried away by emotions when they post online ratings on holidays. However, those who need to work overtime during holidays are found to be driven by bad mood when they post online ratings

A Full Envelope Robust Linear Parameter-Varying Control Method for Aircraft Engines

In order to solve the problem of full flight envelope control for aircraft engines, the design of a linear parameter-varying (LPV) controller is described in this paper. First, according to the nonlinear aerodynamic model of the aircraft engine, the LPV engine model for the controller design is obtained through the Jacobian linearization and fitting technique. Then, the flight envelope is divided into several sub-regions, and the intersection of adjacent sub-regions is not empty. The sub-region LPV controller is designed using the parameter-dependent Lyapunov function (PDLF)-based LPV synthesis method, while eliminating the dependence of the LPV controller on scheduling parameter derivatives. In order to ensure the stability and performance of the aircraft engine across the full flight envelope, a mixing LPV control method is proposed to design the LPV controller in the overall region. The effectiveness of the proposed method is verified by simulating a dual-spool turbofan engine on a nonlinear component level model and comparing the proposed method with the gain scheduling based on PI and H∞ point design