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Urbanization has amplified the importance of three‐dimensional structures in urban environments for a wide range of phenomena that are of significant interest to diverse stakeholders. With the growing availability of 3D urban data, numerous studies have focused on developing visual analysis techniques tailored to the unique characteristics of urban environments. However, incorporating the third dimension into visual analytics introduces additional challenges in designing effective visual tools to tackle urban data's diverse complexities. In this paper, we present a survey on visual analytics of 3D urban data. Our work characterizes published works along three main dimensions (why, what, and how), considering use cases, analysis tasks, data, visualizations, and interactions. We provide a fine‐grained categorization of published works from visualization journals and conferences, as well as from a myriad of urban domains, including urban planning, architecture, and engineering. By incorporating perspectives from both urban and visualization experts, we identify literature gaps, motivate visualization researchers to understand challenges and opportunities, and indicate future research directions. [ABSTRACT FROM AUTHOR]

Producing solar fuels through semiconductor‐based photocatalytic water splitting is one of the main options for worldwide employment of non‐fossil energy sources. Nonetheless, the relatively low efficiency of the known photocatalysts, the high prices of composing elements, and the costly preparation methods render expensive devices that would not be economically competitive with fossil energy sources. Herein, we present a facile method for the preparation of both round hematite (Fe2O3) nanoparticles, with average diameter of (56±7) nm, and of niobium‐doped hematite nanoparticles with similar size and morphology. Thin films of these nanoparticles were assembled through electrophoretic deposition, resulting in homogeneous photoanodes with nanometer thickness that can split water, under simulated solar irradiation, to produce oxygen in a photoelectrochemical cell. The optimization of the film composition and thickness resulted in the improvement of the photocurrent from 352.3 to 1,342.5 μA cm−2 at 1.23 V vs RHE for the pristine hematite and Nb‐doped hematite, respectively, both with thickness of (499±63) nm. This enhancement in the oxidation reaction yield is a clear consequence of the improvement of charge carriers transport along the nanoparticle structure due to niobium doping and adequate light absorption/charge transfer balance of the photoelectrode under operation. [ABSTRACT FROM AUTHOR]

Fire can change gallery forest vegetation structure, thereby altering nutrient fluxes between terrestrial and aquatic ecosystems. In Brazilian savannas, which are fire‐prone ecosystems, the fire regime is changing due to human activities such as converting native vegetation to farmland and urban areas. Uncontrolled wildfires in these savannas can reach gallery forests, which are more sensitive to fire impacts, leading to concerns about the effects of fire on gallery forest vegetation structure and freshwater ecosystems. We analysed the relationships between fire severity (the degree to which the fire has changed an area), percentage of burned area, variation in precipitation with gallery forest and savanna vegetation structure recovery and input of nutrients (NH4, NO2−, NO3− and PO43) to streams for 16 months after a fire event in five watersheds associated with small streams. One year after the fire, vegetation recovery (NDVI) was lower in gallery forest areas than in savanna woodlands, despite the more severe fires in savannas. The short‐term effects of fire on gallery forest vegetation included increased nitrate concentrations in streams, which were also influenced by increased precipitation and the extent of the burned area. The nutrient inputs into the stream stabilized within 1 year. However, gallery forest vegetation did not fully recover at that time and may continue to alter the functioning of the aquatic ecosystem. Together, these results demonstrate the need for an integrated fire management plan that considers both gallery forests and the surrounding savannas in the landscape to address consequences to aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Noise is one of the primary quality‐of‐life issues in urban environments. In addition to annoyance, noise negatively impacts public health and educational performance. While low‐cost sensors can be deployed to monitor ambient noise levels at high temporal resolutions, the amount of data they produce and the complexity of these data pose significant analytical challenges. One way to address these challenges is through machine listening techniques, which are used to extract features in attempts to classify the source of noise and understand temporal patterns of a city's noise situation. However, the overwhelming number of noise sources in the urban environment and the scarcity of labeled data makes it nearly impossible to create classification models with large enough vocabularies that capture the true dynamism of urban soundscapes. In this paper, we first identify a set of requirements in the yet unexplored domain of urban soundscape exploration. To satisfy the requirements and tackle the identified challenges, we propose Urban Rhapsody, a framework that combines state‐of‐the‐art audio representation, machine learning and visual analytics to allow users to interactively create classification models, understand noise patterns of a city, and quickly retrieve and label audio excerpts in order to create a large high‐precision annotated database of urban sound recordings. We demonstrate the tool's utility through case studies performed by domain experts using data generated over the five‐year deployment of a one‐of‐a‐kind sensor network in New York City. [ABSTRACT FROM AUTHOR]

The search for new CoIII‐based drug delivery systems has attracted considerable attention in recent years. In this work, two cobalt complexes with general formula [Co(L)Am](ClO4)n were synthesized, in which L– = (ethyl‐3‐(7‐(diethylamino)‐2‐oxo‐2H‐chromen‐3‐yl)‐3‐oxopropanoate), a coumarin‐β‐keto ester ligand, and Am is the auxiliary amine TPA (tris‐(2‐pyridylmethyl)amine) or Py2en (2‐pyridylmethyl)‐1,2‐diamine). Complexation reactions yielded [CoII(L)TPA]ClO4(1) and [CoIII(L)Py2en](ClO4)2(2), and the CoIII complex (2) was investigated as a potential hypoxia‐activated prodrug prototype. The redox potential of the CoIII/CoII couple (+ 0.152 V vs. standard hydrogen electrode – SHE) was outside the suggested range for activation by cellular reductases. However, (2) was successfully able to release L– in the presence of sodium ascorbate, which was found to be slightly dependent on the O2 concentration. In terms of cytotoxicity, (2) and HL were the least toxic compounds against the tumor cells tested (IC50 > 40 and 100 µm) and nontoxic against normal cells. The results show that complex (2) is a reductively activated non‐toxic carrier system. [ABSTRACT FROM AUTHOR]

Abstract: Advances in technology coupled with the availability of low‐cost sensors have resulted in the continuous generation of large time series from several sources. In order to visually explore and compare these time series at different scales, analysts need to execute online analytical processing (OLAP) queries that include constraints and group‐by's at multiple temporal hierarchies. Effective visual analysis requires these queries to be interactive. However, while existing OLAP cube‐based structures can support interactive query rates, the exponential memory requirement to materialize the data cube is often unsuitable for large data sets. Moreover, none of the recent space‐efficient cube data structures allow for updates. Thus, the cube must be re‐computed whenever there is new data, making them impractical in a streaming scenario. We propose Time Lattice, a memory‐efficient data structure that makes use of the implicit temporal hierarchy to enable interactive OLAP queries over large time series. Time Lattice is a subset of a fully materialized cube and is designed to handle fast updates and streaming data. We perform an experimental evaluation which shows that the space efficiency of the data structure does not hamper its performance when compared to the state of the art. In collaboration with signal processing and acoustics research scientists, we use the Time Lattice data structure to design the Noise Profiler, a web‐based visualization framework that supports the analysis of noise from cities. We demonstrate the utility of Noise Profiler through a set of case studies. [ABSTRACT FROM AUTHOR]

The motivation of this work was to probe whether coordination of esculetin to cobalt(III) could lead to a complex with the required properties to function as a redox-activated drug delivery platform, selective for hypoxic environments. The complex [Co(esc)(py2en)]ClO4·(CH3OH)2 (1) was obtained and fully characterized by CHN elemental analysis, single-crystal Xray diffractometry, UV/Vis and fluorescence spectroscopy, and ESI mass spectrometry. The redox behavior of 1 was evaluated by cyclic and square wave voltammetry analyses in MeCN and PBS buffer, which revealed distinct potentials for the Co3+/Co2+ processes in aqueous and organic solutions. In PBS, the potential is within the accepted ideal range (-0.2 to -0.4 V vs. SHE) for reduction in biological systems. Thus, a selective release of the coumarin ligand in a hypoxic environment upon reduction was simulated by investigating reactions of 1 with sodium dithionite in argon-, air-, and O2-saturated atmospheres. An [O2]-dependent dissociation of esculetin was monitored over a 72 h period at 25 °C by UV/Vis spectroscopy and confirmed by fluorescence spectroscopy and ESI-MS data. These results provide strong evidence of a hypoxia-selective, redox-activated mechanism for the release of esculetin from this cobalt(III) complex. [ABSTRACT FROM AUTHOR]