Physical Structure Research Articles

Magnetite Fe3O4 nanoparticles impregnated on Chlorella vulgaris microalgae: Its role in obtaining hydrogen from the sodium borohydride-hydrolysis

Recently, the single-celled green freshwater microalgae species “Chlorella vulgaris” has attracted the attention of researchers due to its different usage areas. In particular, research focuses on the technology of obtaining bio‑hydrogen with various techniques. This research involves, for the first time, the use of the microalga Chlorella vulgaris as a bio-supporting material for magnetite Fe3O4 nanoparticles (Fe3O4NPs@Chlorella vulgaris) and the production of hydrogen through catalytic hydrolysis of NaBH4 (sodium borohydride, SB) in the presence of the resulting magnetite nanoparticles. Here, detailed kinetic studies were carried out during the SB-hydrolysis by taking magnetite Fe3O4NPs@Chlorella vulgaris and SB in varying amounts and at varying temperatures, and the activation energy and lifetime of magnetite Fe3O4NPs@Chlorella vulgaris was found to be 23.49 kJ mol−1 and 93,280 mol H2 (mol Fe3O4)−1, respectively. No change in the chemical and physical structure of the biocatalyst was observed during the hydrolysis of SB, so only detailed characterization of microalgae and magnetite Fe3O4NPs@Chlorella vulgaris was performed, and the particle size of the catalyst was calculated as 10.19 ± 2.17 nm. The results showed that these Fe3O4NPs@Chlorella vulgaris, which can be easily separated magnetically and have high catalytic activity, are a “clean” and quite surprising catalyst in terms of hydrogen production.

Physical and biochemical characteristics of tropical grass and legume pastures grazed by lambs

AbstractLarge areas of tropical grass pastures are not grazed by lambs because of the difficulties in managing high growth rate swards with high selective animals. The objective of this study was to evaluate the physical and biochemical characteristics of tropical pastures offered to lambs in continuous grazing. An upright grass and a shrub legume were set out in three pasture types and grazed by lambs: (1) aruana grass monoculture (AG—Panicum maximum Jacq. cv. IZ‐5), (2) pigeon pea monoculture (PP—Cajanus cajan [L.] Millsp. cv. Anão) and (3) contiguous swards (CS), half of the paddock with AG (CSAG) and half with PP (CSPP). The pastures were evaluated for structural characteristics, production, nutritional composition and antioxidant concentrations in four periods over 92 days of continuous grazing by lambs. Hand plucking samples, similar to animal diet, were collected for chemical analysis. Regarding height, the PP legume monoculture after 42 days of grazing had uncontrollable growth by the lambs, reaching 1.2 m in height. This same legume but as a CS beside AG (CSPP) was maintained at a lower and similar height throughout the experimental periods. In general, the leaf:stem ratio of the different pastures decreased over the experimental periods from 0.7 to 0.2. In most periods, the CS showed intermediary nutritional quality compared to AG and PP. The alpha‐tocopherol content was similar among swards, with an average of 137.2 ± 13.67 mg/kg of green matter (p > .05). Pigeon pea showed the highest levels of total tannin and condensed tannin at 63 and 92 days (p < .05). The use of tropical grass together with a legume provides a better physical structure of the pigeon pea for grazing lambs than when monoculture of this species.

Magnetic Anisotropy Dominates over Physical and Magnetic Structure in Performance of Magnetic Nanoflowers

Magnetic nanoparticles are indispensable in many biomedical applications, but it remains unclear how the composition and structure will influence the application specific performance. We consider two compositions, ferrite and cobalt ferrite, synthesized under conditions that create aggregated multi‐core nanoparticles, called nanoflowers. Each nanoflower has an ionic surfactant or dextran to provide colloid stability in water. The composition, but not the coating, greatly impacts the heating output and the magnetic particle imaging tracer quality (with cobalt ferrite significantly reduced compared to ferrite). The cobalt ferrite nanoflowers have a core/shell structure with a reduced magnetization, which limits the effective magnetic anisotropy of the individual cobalt ferrite nanoflowers as well as the magnetic interactions among the nanoflowers. Both limitations significantly reduce the overall increase in the magnetic anisotropy with increasing magnetic field and consequently the nanoflowers’ efficacy for heating and imaging. Despite this, the formation of denser‐packed clusters and chains with external magnetic field in the ionic surfactant‐cobalt ferrite nanoflowers overcomes some of the shell's detrimental effects, resulting in better heating and imaging properties compared to the dextran‐cobalt ferrite. In short, the magnetic anisotropy dominates over physical and magnetic structure in the performance of the studied nanoflowers for heating and imaging applications.

Distributing a Sane Beverage? The Social Differentiation of Access to Water in Paris

Water management depends on both the physical and social structures of large cities. In Paris, these elements interacted to limit and constrain access to water for large segments of the population for long periods of time. The very unequal distribution of property in the city is central to understanding water regimes in Paris and their evolution over time. This article analyzes the evolution of water systems in Paris from the mid-nineteenth century to the mid-twentieth century, considering access to water (and its quality) as well as the provision of sewers to remove waste soiled materials. Important social variations in the modalities of access to water within the city persisted for a long time. They were a consequence of choices made in organizing the distribution of water in the city.

Digital Twins in Manufacturing: A Survey of Current Practices and Future Trends

Digital Twin (DT) is the advanced tool of smart manufacturing which provides a proper way to model, analyse, and control the physical systems. A DT is the lifelike rendition of a physical object or phenomenon that uses real-time actual phenomena data to depict its actions, efficiency, and responses within the surrounding context. This technology allows electronic manufacturers to obtain a real-time stream of their systems, in which predictive maintenance, increased operation effectiveness, and improved product quality can be attained. By developing an ever-evolving replica of the physical structures, systems or even operation lines, Digital Twins enable the functionality of exploring various demanding circumstances and schemata, all in order to make effective decisions. When the manufacturing environments are rapidly changing, and there are more interconnections between them, the use of Digital Twins is especially useful. They continue improvement by highlighting problems, forecasting failure, and making choices based on data. The purpose of this article is to examine smart manufacturing via the lens of IoT DT technology. It gives general information about its uses, such as in the processes, time-saving and safety measures. As well, the paper considers the difficulties related to the practical application of DT, including costs, data management, and requirements for the formation of standards. Thus, based on analysing future developments and the role of Digital Twins as an innovation enabler in different industries, this study can benefit scholars, practitioners, and politicians who look forward to unlocking the potential of this innovative solution.

Herbivore regulation of savanna vegetation: Structural complexity, diversity, and the complexity–diversity relationship

AbstractLarge mammalian herbivores exert strong top‐down control on plants, which in turn influence most ecological processes. Accordingly, the decline, displacement, or extinction of wild large herbivores in African savannas is expected to alter the physical structure of vegetation, the diversity of plant communities, and downstream ecosystem functions. However, herbivore impacts on vegetation comprise both direct and indirect effects and often depend on herbivore body size and plant type. Understanding how herbivores affect savanna vegetation requires disaggregating the effects of different herbivores and the responses of different plants, as well as accounting for both the structural complexity and composition of plant assemblages. We combined high‐resolution Light Detection and Ranging (LiDAR) with field measurements from size‐selective herbivore exclosures in Kenya to determine how herbivores affect the diversity and physical structure of vegetation, how these impacts vary with body size and plant type, and whether there are predictable associations between plant diversity and structural complexity. Herbivores generally reduced the diversity and abundance of both overstory and understory plants, though the magnitude of these impacts varied substantially as a function of body size and plant type: only megaherbivores (elephants and giraffes) affected tree cover, whereas medium‐ and small‐bodied herbivores had stronger effects on herbaceous diversity and abundance. We also found evidence that herbivores altered the strength and direction of interactions between trees and herbaceous plants, with signatures of facilitation in the presence of herbivores and of competition in their absence. While megaherbivores uniquely affected tree structure, medium‐ and small‐bodied species had stronger (and complementary) effects on metrics of herbaceous vegetation structure. Plant structural responses to herbivore exclusion were species‐specific: of five dominant tree species, just three exhibited significant individual morphological variation across exclosure treatments, and the size class of herbivores responsible for these effects varied across species. Irrespective of exclosure treatment, more species‐rich plant communities were more structurally complex. We conclude that the diversity and architecture of savanna vegetation depend on consumptive and nonconsumptive plant–herbivore interactions; the roles of herbivore diversity, body size, and plant traits in mediating those interactions; and a positive feedback between plant diversity and structural complexity.

Bright-rimmed clouds in IC 1396

Aims. We investigate the dynamical and physical structures of bright-rimmed clouds (BRCs) in a nearby H II region. We focused on carbon- and oxygen-bearing species that trace photon-dominated regions (PDRs) and warm molecular cloud surfaces in order to understand the effect of UV radiation from the exciting stars on the cloud structure. Methods. We mapped four regions around the most prominent BRCs at scales of 4–10 arcmin in the H II region IC 1396 (IC 1396A, B, D, and E) in [C II] 158 µm with (up)GREAT on board SOFIA. IC 1396 is predominantly excited by an O6.5V star. Toward IC 1396A, we also observed [O I] 63 µm and 145 µm. We combined these observations with JCMT archive data, which provide the low-J transitions of CO, 13CO, and C18O. All spectra are velocity-resolved. Results. The line profiles in the four mapped regions show a variety of velocity structures, which we investigated in detail for all observed emission lines. IC 1396B and D show clearly distinct velocity components that overlap along the line of sight. We find no clear sign of photoevaporating flows in the [C II] spectra, although the uncertainty in the location of the BRCs along the line of sight makes this interpretation inconclusive. Our analysis of the [13C II] emission in IC1396 A, which has the best signal-to-noise ratio, suggests that the [C II] is likely mostly optically thin. The heating efficiency, measured by the ([C II]+[O I] 63 µm)/far-infrared intensity ratio, is higher in the northern part of IC 1396A than in the southern part, which may indicate a difference in the dust properties of the two areas. Conclusions. The complex velocity structures identified in the BRCs of IC 1396, which is apparently a relatively simple H II region, highlight the importance of velocity-resolved data for disentangling different components along the line of sight and thus facilitating a detailed study of the dynamics of the cloud. We also demonstrate that the optically thin [13C II] and [O I] 145 µm emission lines are essential for a conclusive interpretation of the [C II] 158 µm and [O I] 63 µm line profiles.

Is it me or is it you? Physiological effects of the honey bee microbiota may instead be due to host maturation.

Microbiota-mediated impacts on host physiology and behavior have been widely reported in honey bees (Apis mellifera). However, most of these studies are conducted in artificial lab settings and fail to take into account, or make incorrect assumptions about, the complex physical and social structures inherent to natural hive conditions. A new study by Liberti et al. (J. Liberti, E. T. Frank, T. Kay, L. Kesner, et al., mBio 15:e01034-24, 2024, https://doi.org/10.1128/mbio.01034-24) identifies one such overlooked aspect-the behavioral maturation from nurses to foragers-that can be a serious confounding factor in bee microbiota experiments. Using cuticular hydrocarbon profiling to discern between the two maturation states, they find that multiple physiological and behavioral differences between age-matched lab bees could potentially be explained by their maturation state instead of the intended treatment conditions, such as microbial inoculation. This study serves as a stark wake-up call on the necessity of careful replication and cross-disciplinary knowledge transfer (e.g., between animal specialists and microbiologists) in order to truly understand complex host-microbe systems.

Intelligence: Natural, artificial, or what?

We consider the competing attributes of natural intelligence (NI) and artificial intelligence (AI). Attention is paid to conceptual, theoretical, stylistic and structural aspects of both, and non-human intelligence. Intelligence is related to information processing and current views of physical structuring. Means of distinguishing between NI and AI are noted, and neural and digital structures are described. Pribram's bi-computational neural networks are introduced, and high-level Pribram computation is discussed. We describe the hierarchical Aquarium scheme, along with an AI implementation, and conclude with a proposition for future quantum-based artificial intelligence.

Direct Recycling of LixNi0.5Mn0.3Co0.2O2 from Production Scrap and End‐of‐Life Batteries using Solid‐State Relithiation

Direct recycling of Li‐ion battery cathodes offers a sustainable and potentially cost‐effective alternative to conventional methods, often involving complex chemical processes and significant material losses. This study focuses on the relithiation of cathode materials from quality control reject (QCR) and end‐of‐life (EoL) Li‐ion cells to restore their physical structure, morphology, and electrochemical performance. Two NMC532/graphite pouch cells from the same manufacturer were studied. QCR cells, stored under ambient conditions, experienced corrosion and degradation before recycling, while EoL cells were cycled to the end of life. The cells were disassembled, and the cathode materials were delaminated using NaOH solution, then relithiated with LiOH at 700°C for 15 hours in the air. Extensive characterization analyzed elemental composition, structural properties, thermal stability, and particle size distribution. Results indicated that relithiation successfully restored lithium content and improved the structural ordering and morphology of the cathode materials. The electrochemical performance of the relithiated cathodes exhibited good stability over 100 charge‐discharge cycles. The relithiated QCR samples achieved a capacity of 155.57 mAh g⁻¹, while EoL samples reached 152.53 mAh g⁻¹, comparable to pristine materials. This study highlights relithiation's potential to extend the lifecycle of Li‐ion cathodes, contributing to a more sustainable circular economy for battery materials.

Comparative Analysis of the "H"-shaped Symbol from Göbekli Tepe and the Ritual "Binocular-shaped" Ceramics of the Trypillia Culture in Light of Ancient Farmers' Cosmological Beliefs

This article is dedicated to a comprehensive analysis and interpretation of the sacred "H"-shaped symbolism, which originates from the ancient temple complex of hunter-gatherers and early farmers of the Near East – Göbekli Tepe. The research identifies and analyzes a similar symbol found in the religious complex of ancient farmers in the territory of modern Ukraine, specifically in the Trypillia culture and its ceramic artifacts known as "Trypillia binoculars." A comparative analysis of these symbols is conducted within the context of the cosmological beliefs of early farming societies in Asia and Europe. Special attention is given to interpreting this symbolism as a reflection of complex religious and philosophical concepts related to the cyclicality of nature, the movement of celestial bodies, and the unity of heaven and earth. The research examines the architectural features of Göbekli Tepe, particularly the arrangement of the T-shaped columns, and their potential astronomical purpose. The author hypothesizes a connection between the physical structure of the temple complex, its T-shaped columns, and the formation of abstract "H"-type symbols. Parallels are drawn between the symbolism of Göbekli Tepe and the ritual artifacts of the Trypillia culture, allowing the hypothesis of shared cosmological concepts between various early farming cultures, despite significant geographical and temporal distances. This article offers a new perspective on the development of religious thought in ancient societies, highlighting the depth and complexity of their spiritual ideas. The findings contribute to a better understanding of the cultural connections and exchange of ideas between ancient civilizations of the Near East and Europe.

Seasonal Variations of Ice-Covered Lake Ecosystems in the Context of Climate Warming: A Review

The period of freezing is an important phenological characteristic of lakes in the Northern Hemisphere, exhibiting higher sensitivity to regional climate changes and aiding in the detection of Earth’s response to climate change. This review systematically examines 1141 articles on seasonal frozen lakes from 1991 to 2021, aiming to understand the seasonal variations and control conditions of ice-covered lakes. For the former, we discussed the physical structure and growth characteristics of seasonal ice cover, changes in water environmental conditions and primary production, accumulation and transformation of CO2 beneath the ice, and the role of winter lakes as carbon sources or sinks. We also proposed a concept of structural stratification based on the differences in physical properties of ice and solute content. The latter provided an overview of the ice-covered period (−1.2 d decade−1), lake evaporation (+16% by the end of the 21st century), the response of planktonic organisms (earlier spring blooming: 2.17 d year−1) to global climate change, the impact of greenhouse gas emissions on ice-free events, and the influence of individual characteristics such as depth, latitude, and elevation on the seasonal frozen lakes. Finally, future research directions for seasonally ice-covered lakes are discussed. Considering the limited and less systematic research conducted so far, this study aims to use bibliometric methods to synthesize and describe the trends and main research points of seasonal ice-covered lakes so as to lay an important foundation for scholars in this field to better understand the existing research progress and explore future research directions.

Ferromagnetic-Antiferromagnetic Coupling in Gas-Phase Synthesized M(Fe, Co, and Ni)-Cr Nanoparticles for Next-Generation Magnetic Applications.

Combining ferromagnetic-antiferromagnetic materials in nanoalloys (i.e., nanoparticles, NPs, containing more than one element) can create a diverse landscape of potential electronic structures. As a result, a number of their magnetic properties can be manipulated, such as the exchange bias between NP core and shell, the Curie temperature of nanoparticulated samples, or their magnetocaloric effect. In this work, such a family of materials (namely M-Cr NPs where M is Fe, Co, Ni, or some combination of them) is reviewed with respect to the tunability of their magnetic properties via optimized doping with Cr up to its solubility limit. To this end, gas-phase synthesis has proven a most effective method, allowing excellent control over the physical structure, composition, and chemical ordering of fabricated NPs by appropriately selecting various deposition parameters. Recent advances in this field (both experimental and computational) are distilled to provide a better understanding of the underlying physical laws and point toward new directions for cutting-edge technological applications. For each property, a relevant potential application is associated, such as memory cells and recording heads, induced hyperthermia treatment, and magnetic cooling, respectively, aspiring to help connect the output of fundamental and applied research with current real-world challenges.

Thermochemistry of the Mantle Transition Zone Beneath the Western Pacific

AbstractThe Earth's mantle transition zone has significant control on material flux between upper and lower mantle, thus constraining its properties is imperative to understand dynamic processes and circulation patterns. Global seismic data sets to study the transition zone typically display highly uneven spatial distribution. Therefore, complementary geometries are essential to improve knowledge of physical structures, thermochemistry, and impact on convection. Here, we present a new automated approach utilizing machine learning to analyze large seismic data sets, and derive high‐resolution maps of transition zone discontinuity properties. Seismic measurements from ScSScS precursors are integrated with mineralogical modeling to constrain thermochemistry of the western Pacific subduction zone. Our models map recent subduction patterns through the transition zone, indicating stagnation of slabs and accumulation of basalt at its base, and interaction between stagnant slabs and plumes. These results suggest that the thermochemical properties of upper mantle discontinuities can provide high‐resolution images of mantle circulation patterns.

Form-Finding of Tensegrity Basic Unit with Equal Cable Length

Tensegrity is a lightweight, self-stressing, and self-stabilizing structure made up of cables and bars, with each member bearing either tension or compression but not affected by shear stress. This design allows for optimal utilization of the material properties of the members. In a tensegrity basic unit, the bar members are of equal length, while the cable members come in three lengths: lower-end surface horizontal cable, upper-end surface horizontal cable, and stayed cable. The tensegrity basic unit with equal cable length simplifies this further by ensuring that all cables are the same length, resulting in a structure with only two member lengths, i.e., bar length and cable length, enhancing interchangeability. In order to find the form without the action of external forces, the force density coefficient ratio is introduced. By performing a force balance analysis on any node of the unit, the equilibrium equation of the structure is determined, incorporating the additional constraint of equal cable length. Two methods are employed to ascertain the force density coefficient ratio of each member in the unit: the theoretical derivation method based on the stable configuration condition of the tensegrity basic unit with equal cable length, and the method of solving the characteristic equations of the force density matrix. A program is developed to validate the form-finding method using basic units with three, four, five, and six bars as examples. The results show that the model accurately represents the physical structure, confirming the reliability of the form-finding methods.

Long-Haul Truck Drivers' Perceptions of Truck Stops and Rest Areas: Focusing on Health and Wellness.

The work and life routine of long-haul truck drivers (LHTDs) involve the use of truck stops and rest areas to meet their basic human needs. These extensions of their workspaces on the road do not always offer adequate physical structures and services that drivers need for optimal health. This study aimed to evaluate long-haul truck drivers' perceptions of food services, safety, physical activity, rest, and personal hygiene offered at truck stops and rest areas, as well as the correlation between these perceptions and sociodemographic, health, and work conditions variables. A cross-sectional, quantitative, and descriptive study was conducted with long-haul truck drivers from the southern region of Brazil. For data collection, a sociodemographic questionnaire and a Likert scale on food, rest, personal hygiene, safety, and physical activity services offered at truck stops and rest areas along Brazilian roads from March to August 2023 were used. The data were analyzed with simple frequency descriptive statistics. The sample consisted of 175 long-haul truck drivers. Out of these, 70.29% declared that the services of the truck stops and rest areas were charged; more than half (53.59%) of the professionals evaluated the rest service as "good" or "excellent"; the food services were "good" or "excellent" for 42.24% of the drivers. The spaces for physical activities were the worst evaluated as "bad" or "terrible" by 41.61%, followed by bathroom services (28.42%) and safety (34.24%). Rest and feeding services had better evaluations, while the services of bathroom, safety, and physical activity presented worse evaluations. Variables such as nationality, weekly working days, and marital status presented positive significance and influenced drivers' perceptions of the services offered at truck stops and rest areas. Drivers who were Brazilian and worked more than five days a week negatively evaluated the services of rest (p = 0.018), safety [0.020], physical activity (0.003), and bathrooms (0.020). In addition, the physical activity services were better evaluated by single drivers than married drivers. These findings suggest that the work conditions and nationality may influence LHTDs' perceptions of services and structures of truck stops and rest areas. These findings may reflect a lack of investments and support efforts to improve basic services such as personal hygiene, a safe environment, and physical exercises, which are fundamental to the health of the workers and aimed at reducing vulnerability and a sedentary lifestyle and meeting the basic human needs of LHTDs.

Pre-formulation Characteristics of Ticagrelor: A Comprehensive Exploration

Ticagrelor is a potent antiplatelet agent that plays a crucial role in preventing cardiovascular events. Preformulation studies are essential in the drug development process to assess the physicochemical properties of the active pharmaceutical ingredient (API) and its suitability for formulation into a final dosage form. This abstract provides an overview of the preformulation studies conducted on Ticagrelor. The preformulation studies encompassed an extensive analysis of Ticagrelor's physical properties, including solubility, melting point, and crystal structure. Additionally, the drug's stability under various environmental conditions, such as temperature and humidity, was evaluated. Spectroscopic techniques, such as UV-Vis and FTIR, were used to characterize the chemical structure of the compound. The results of these preformulation studies provide valuable insights into the potential challenges and opportunities in formulating Ticagrelor into stable and bioavailable dosage forms. These findings will guide further formulation development and optimization, ensuring the delivery of an efficacious and safe drug product to patients.

Ichnological indicators of physico-chemical stresses in wave- to tide-dominated Miocene shallow marine environments (Argentine Patagonia)

An integrated analysis of ichnological and sedimentological features in ancient successions provides a robust dataset of high-resolution interpretations of environmental parameters, encompassing both depositional and ecological aspects. By characterising discrete and recurring bioturbation patterns in the Puerto Madryn Formation (Late Miocene, Argentine Patagonia), we arrive at key knowledge about predominant environmental stresses within transgressive phase shallow marine and estuarine systems, shedding light on their palaeoenvironmental implications. Given the inherent complexities of coastal settings, including the challenges posed by omission/erosion surfaces, it becomes imperative to consider the intricate interplay of multiple depositional processes and environmental factors.Through a detailed integration of sedimentological and ichnological approaches, we discern the establishment of a wave-dominated system overlain by a tide-dominated estuarine system.The wave-dominated marine system involves tabular bodies extending laterally over tens of kilometres, with upward fining and coarsening successions from the mid- to lower-shoreface to offshore-shelf environments. The influence of waves and tides on these systems is discussed in the absence of physical sedimentary structures and the need to find elements that bring us closer to elucidating whether waves or tidal processes influence shoreface to offshore systems. The ichnological assemblages allow for the characterisation of Cruziana ichnofacies with proximal (Taenidium and Thalassinoides), archetypal (Asterosoma, Chondrites, Cylindrichnus, Ophiomorpha, ?Rhizocorallium, Rosselia, Scolicia, Sinusichnus, Siphonichnus, Teichichnus, and Thalassinoides), and distal expressions (Chondrites, Helicodromites, Phycodes, Thalassinoides, and ?Zoophycos) in the lower shoreface to lower offshore and transitional settings with the shelf. However, the transition from these deposits to Chondrites-dominated beds associated with lower offshore to shelf environments—determined by changes in oxygenation, nutrients, and energy conditions—impedes assignment of all the successions to a particular ichnofacies.The tide-dominated estuarine system features wide, channel-shaped bodies filled with sandy to heterolithic facies, interpreted as intertidal and subtidal deposits. To differentiate between estuary mouths and other settings, the analysis involved characterisation of transgressive and regressive surfaces, ichnological assemblages, and facies distribution, determining net sediment movement—whether landwards or seawards—and its influence on system classification. The ichnological assemblages could be assigned to the Skolithos (Arenicolites, Gyrolithes, Maiakarichnus, Ophiomorpha, Schaubcylindrichnus, Skolithos, and Thalassinoides) and Cruziana ichnofacies (Ophiomorpha, Rosselia, Scolicia, and Siphonichnus). Variations in diversity and abundance often help to determine certain stressful conditions, although the transition to more open areas is discussed, addressing how it could modify the typical models linked with a direct relationship between abundance/diversity and physico-chemical stress.

Influence of TiO2-MWCNTs nanohybrid material on the corrosion resistance of epoxy low-zinc coatings

Aiming to improve the corrosion resistance of epoxy low-zinc coatings in marine environments, TiO2-MWCNTs nano-hybridized materials were prepared by sol-gel method in this study, and different contents of reinforcing phases were implanted as to improve the anticorrosive properties of epoxy low-zinc coatings. Characterization of the microscopic morphology, physical phase composition and chemical structure of the TiO2-MWCNTs materials demonstrated that the TiO2 hybridization was successful and the loading of TiO2 improved the dispersion of MWCNTs. To investigate the effect of the additive reinforcing phase on the mechanical and corrosion resistance of the coatings by characterizing the coating microscopic morphology, surface wettability, substrate adhesion, and impedance changes at different immersion times. The above results demonstrated that the epoxy composite coating had lower surface energy and 16 % larger surface contact angle compared with the pure epoxy low-zinc coating; the 0.4 wt% TiO2-MWCNTs/epoxy composite coating had the highest adhesion of 6.52 MPa. The electrochemical test results indicated that the TiO2-MWCNTs/epoxy low-zinc composite coating had the largest self-corrosion potential, the smallest self-corrosion current density of 4.538 μA/cm2, and the largest impedance of 242.3 KΩ/cm2. The addition of TiO2-MWCNTs reinforcing phase significantly extended the barrier protection time of the epoxy low zinc coating and maintained good corrosion resistance throughout the immersion cycle.

Unoccupied-Aerial-Systems-Based Biophysical Analysis of Montmorency Cherry Orchards: A Comparative Study

With the global population on the rise and arable land diminishing, the need for sustainable and precision agriculture has become increasingly important. This study explores the application of unoccupied aerial systems (UAS) in precision agriculture, specifically focusing on Montmorency cherry orchards in Payson, Utah. Despite the widespread use of UAS for various crops, there is a notable gap in research concerning cherry orchards, which present unique challenges due to their physical structure. UAS data were gathered using an RTK-enabled DJI Mavic 3M, equipped with both RGB and multispectral cameras, to capture high-resolution imagery. This research investigates two primary applications of UAS in cherry orchards: tree height mapping and crop health assessment. We also evaluate the accuracy of tree height measurements derived from three UAS data processing software packages: Pix4D, Drone2Map, and DroneDeploy. Our results indicated that DroneDeploy provided the closest relationship to ground truth data with an R2 of 0.61 and an RMSE of 31.83 cm, while Pix4D showed the lowest accuracy. Furthermore, we examined the efficacy of RGB-based vegetation indices in predicting leaf area index (LAI), a key indicator of crop health, in the absence of more expensive multispectral sensors. Twelve RGB-based indices were tested for their correlation with LAI, with the IKAW index showing the strongest correlation (R = 0.36). However, the overall explanatory power of these indices was limited, with an R2 of 0.135 in the best-fitting model. Despite the promising results for tree height estimation, the correlation between RGB-based indices and LAI was underwhelming, suggesting the need for further research.