Search Results (26)

Global climate change has intensified the heterogeneity of precipitation regimes in subtropical regions, and the increasing frequency of extreme drought events poses a significant threat to biogeochemical cycling in forest ecosystems. Yet, the pathways by which reduced precipitation regulates deadwood decomposition and thereby influences soil nutrient pools remain poorly resolved. Here, we investigated a Cunninghamia lanceolata (Lamb.) Hook. plantation in subtropical China under ambient precipitation (CK) and precipitation reduction treatments of 30%, 50%, and 80%, systematically examining how reduced precipitation alters the chemical properties of deadwood substrates and, in turn, soil nutrient status. Our findings reveal that (1) as precipitation declined, soil water content decreased significantly (p < 0.01), while deadwood pH declined and total organic carbon (TOC), nonstructural carbohydrates (NSCs), and lignin content markedly accumulated (p < 0.01); (2) these shifts in deadwood chemistry affected feedback mechanisms, leading to the suppression of soil nutrient pools: extreme drought (80% reduction) significantly reduced soil TOC, dissolved organic carbon (DOC), total nitrogen (TN), and total phosphorus (TP) (p < 0.01) and inhibited N and P mineralization, whereas the 30% reduction treatment elicited a transient increase in soil microbial biomass carbon (MBC), indicative of microbial acclimation to mild water stress; and (3) principal component analysis (PCA) showed that the 80% reduction treatment drove lignin accumulation in deadwood, while the 30% reduction treatment exerted the greatest influence on soil DOC, TOC, and MBC; partial least squares path modeling (PLS-PM) further demonstrated that soil water content and deadwood substrate properties (pH, lignin, soluble sugars, TOC, C/N, and lignin/N) were strongly negatively correlated (r = −0.9051, p < 0.01), and that deadwood chemistry was, in turn, negatively correlated with soil nutrient variables (pH, TOC, DOC, MBC, TP, TN, and dissolved organic nitrogen [DON]; r = −0.8056, p < 0.01). Together, these results indicate that precipitation reduction—by drying soils—profoundly modifies deadwood chemical composition (lignin accumulation and NSC retention) and thereby, via slowed organic-matter mineralization, constrains soil nutrient release and accumulation. This work provides a mechanistic framework for understanding forest carbon–nitrogen cycling under climate change. Full article

Oilfield data is characterized by complex types, large volumes, and significant noise interference, so data cleansing has become a key procedure for improving data quality. However, the traditional data cleansing process needs to deal with multiple types of problems, such as outliers, duplicate data, and missing values in turn, and the processing steps are complex and inefficient. Therefore, an integrated data cleansing and function fitting method is established. The fine-mesh data density analysis method is utilized to cleanse outliers and duplicate data, and the automated segmented fitting method is used for missing data imputation. For the real-time data generated during drilling or well logging, data cleansing is realized through grid partitioning and data density analysis, and the cleansing ratio is controlled by data density threshold and grid spacing. After data cleansing, based on similar standards, the cleansed data is segmented, and the fitting function type of each segment is determined to fill in the missing data, and data outputs with any frequency can be obtained. For the analysis of the hook load data measured by sensors at the drilling site and obtained from rig floor monitors or remote centers, the data cleansing percentage reaches 98.88% after two-stage cleansing, which still retains the original trend of the data. After data cleansing, the cleansed data are modeled through the automated segmented fitting method, with Mean Absolute Percentage Errors (MAPEs) less than 3.66% and coefficient of determination (R²) values greater than 0.94. Through the integrated data processing mechanism, the workflow can synchronously eliminate outliers and redundant data and fill in the missing values, thereby dynamically adapting to the data requirements of numerical simulation and intelligent analysis and significantly improving the efficiency of on-site data processing and decision-making reliability in the oilfield. Full article

If modern Western disciplinary structures, laid forth by Dilthey and others in the 19th century, have helped structure the world in ways that bring about climate change and gross economic inequities (along with many “good” things such as vaccines and some modern comforts), how might we re-structure our thinking and learning in ways that address these violent lacunae? What does it mean to educate in a truly globalized world that is facing climate change, extinction, and growing injustice? The answer to that surely cannot be “more of the same”. Following the work of critical theorists and the ideas of Paulo Freire and bell hooks, among others, this essay argues that education should be about imagining and working toward a more just and ecologically sound version of the planetary future in a way that is attentive to as much input as possible from multiple perspectives (human and non). The goals of such an education are connective, grounding, and encountering “others” rather than reductive, productive, and geared toward technology transfer. What would it mean to undiscipline or open our disciplinary categories in ways that reattune us to the changing, entangled planet of which we are a part? What will it take to develop planetary humanities and technologies? If humans are not exceptions to the rest of the natural world, and if the nonhuman world is not just dead matter to be used toward human ends, then how do we go about re-grounding our epistemologies within the planet, rather than continuously thinking “out of this world”? The first part of this essay offers a critique of the reductive and productive model that turns the world into a “standing reserve” for use by some humans. The second part of the essay outlines some principles for knowledge that are more connective, grounding and enable us to counter the multiple others within the planetary community. Such “planetary” knowledge reminds humans of the humus of our humanity, connects us to other life found through compassion (to suffer with), reminds us of the justice of good company (sharing of bread/resources), and focuses on the playfulness of public, political conversations (the ability to be converted to another’s point of view). In the third part, I suggest some grounded metaphors for planetary thinking: wild and slow thinking, elemental and grounded thinking, and creaturely and mycelium thinking. Full article

In Europe, long-distance transport of wood from landings to consumers is most often carried out by trucks and trucks with trailers. In forests located mainly in mountainous areas with rugged terrain and frequent curves, the construction of forest roads is complicated and often access for trucks with trailers is difficult or there is not enough space on the landing for maneuvers. In these cases, the truck leaves the trailer next to the public road and without it moves to the landing and loads the wood with Palafinger hydraulic crane model Epsilon Kran GmbH mounted on it, which it transfers to the trailer on the way back. Then, the truck moves to the landing to load itself, returns, hooks up the trailer and transports the wood to the customer. This study, conducted in a coniferous stand in Bulgaria, aimed to determine and develop models for the productivity and costs associated with transporting a truck with a trailer and to evaluate the suitability of this method. To study this very common method of long-distance transport, observations were made of 185 turns of a truck with a trailer operating with coniferous wood in Rila-Rhodope Mountain Massif, Southern Bulgaria. It was found that the duration of the working cycle is affected by the total mileage (average 65.41 km), the volume of the load and the number of logs. The productivity with and without delays, 7.80 and 7.30 m³/h, respectively, is affected by the mileage and the volume of the wood, while the corresponding transportation productivity (177.46 and 167.24 m³ km/h) is affected by the transport distance loaded and the volume of the load. To increase efficiency and reduce the cost of transporting wood over long distances, investments are needed to improve forest roads to eliminate the need to uncouple the trailer. Full article

Mixing and matching N₂-fixing leguminous species is a crucial strategy to enhance quality and efficiency in sustainable forestry. Tree leaves and rhizosphere are primary sites for matter and energy exchange, functioning as key assimilation organs that forests provide for ecological services. The introduction of functional species alters soil properties, which, in turn, directly or indirectly shape leaf functional traits, soil microbial dynamics, and their association. However, the correlation between aboveground functional traits and belowground rhizosphere soil microorganisms of dominant tree species in mixed leguminous and non-leguminous forests remains unclear. In this study, the responses and correlations of leaf functional traits and rhizosphere soil microbial communities of Castanopsis hystrix Hook. f. & Thomson ex A. DC. across three forest types were investigated. A pure forest (PF) of C. hystrix was designated as control forest, while a leguminous mixed forest (LMF) consisting of C. hystrix and the leguminous species Acacia mangium Willd. as well as a non-leguminous mixed forest (NMF) comprising C. hystrix and the non-leguminous species Schima superba Gardner & Champ. served as experimental forests. Seven leaf functional trait indices were measured, and the high-throughput sequencing of soil microbial communities was included in the analysis. The results were as follows: Firstly, compared to the pure forest, the specific leaf area (SLA) of C. hystrix significantly decreased in both mixed forest types (p < 0.05). Additionally, in comparison to the pure forest, the leaf area (LA) and leaf organic carbon content (LOC) of C. hystrix significantly reduced (p < 0.05), whereas the leaf total phosphorus content (LTP) significantly increased in the non-leguminous tree species mixed forest (p < 0.01). The leaf dry matter content (LDMC), relative chlorophyll content (RCC), and leaf total nitrogen content (LTN) of C. hystrix exhibited no significant differences among the three forest types (p > 0.05). Secondly, neither the dominant phyla of rhizosphere soil microorganisms nor the bacterial richness and diversity had differences in the mixed forests. However, the richness and diversity of rhizosphere soil fungi significantly increased in the mixed forests, and those in the leguminous mixed forest exhibited more positive effects compared to those in the non-leguminous mixed forest. Finally, redundancy analysis (RDA) showed significant correlations between plant leaf functional traits and rhizosphere soil microorganisms. Specifically, LDMC, SLA, LTN, and LTP of C. hystrix showed significant correlations with differences in the structure of bacterial community (p < 0.05), and LTN was significantly correlated with differences in the structure of the fungal community (p < 0.05). In summary, we found that plant leaf functional traits and the community of rhizosphere soil microorganisms displayed significant differences in the mixed forests, and those mixed with leguminous trees may further enhance the assimilation processes by modifying the utilization of nutrients such as carbon, nitrogen, and phosphorus by plants and microorganisms. Meanwhile, our results support the interaction of physiological and ecological processes between the aboveground and belowground parts of C. hystrix. These findings emphasize the important roles of N₂-fixing leguminous trees and synergy of aboveground–belowground processes in establishing sustainable artificial forests. Full article

Since the 2022 death of Mahsa Jina Amini in custody of the Guidance Patrol or morality police in Tehran, Iran, Persepolis by Marjane Satrapi can also function in the classroom as a comics touching point for human rights discourses around the world and in particular—though not exclusively—those that impact women. Kimberlé Crenshaw, who brought intersectionality to the forefront of cultural and political discourses in 1989, has used the phrase “say her name” to draw attention to the deaths of women and children, especially Black women and children, at the hands of law enforcement officers. Chants of “Say her name, Mahsa Amini”, rang among protesters outside Khalifa International Stadium in Qatar ahead of Iran’s first match of the World Cup 2022 against England. Now in 2025, cultural conversations around feminism and creativity as resistance can turn to the woman, life, freedom movement in Iran. Shervin Hajipour’s song “Baraye”, meaning “for” in Persian, which was inspired by tweets echoing protesters’ calls for change, became an anthem of the uprising and exists in comic art as well as song. The comics classroom can address the concerns and issues surrounding Amini’s death and the ongoing relevance of Persepolis as a coming-of-age text about living as a woman in Iran. In dialogue with the works of Sidonie Smith, Julia Watson, Hillary Chute, Sally Munt, and bell hooks, this piece addresses the pedagogy of human rights through comic art as crisis witnessing. With attention to comics material from two members of the Iranian diaspora, Shabnam Adiban and Farid Vahid, from the 2024 collection Woman, Life, Freedom, put together by Satrapi, this piece navigates potential Orientalism and Islamophobia in the Western classroom through engagement with intersectional feminism. Full article

Illicium verum Hook. f. (star anise) is a highly important plant in terms of both its edible and medicinal properties and its economic value. The suitable habitat for star anise may undergo alterations in response to climate changes and human activities, which in turn might impact its quality. To ensure the future introduction and protection of star anise, it is crucial to analyze the impacts of climate change on the potential distribution of the species. The approach presented in this study integrates the MaxEnt model and chemical composition analysis to assess the potential distribution patterns of star anise in response to climate change and evaluate the impact of environmental variables on its quality. The results revealed that the soil pH, mean temperature of the coldest quarter, mean diurnal range, precipitation of the warmest quarter and annual precipitation were the main factors affecting the current distribution of I. verum. The current area of suitable habitat is approximately 17.6 × 10⁴ km², accounting for 74% of the total area of Guangxi Province. Under the future climate scenarios, the overall pattern of the potential distribution range shifted northwards, and the SSP3126 scenario showed the most significant increase in the area. By utilizing comprehensive 2D chromatography technologies, 111 volatile compounds present in the 61 batches of star anise were identified. Further analysis via chemometric methods revealed that the components β-bisabolene, caryophyllene, 4-methoxyphenylacetone, cis-β-farnesene, anethole and linalool could serve as potential markers for distinguishing the quality of star anise from different geographical origins. Finally, a stepwise regression model between chemical compositions and environmental variables was established, and based on this, a quality zoning map was subsequently plotted. This study provides valuable scientific insights for resource conservation, planting site selection and quality control for star anise. Full article

Firmly, the bearing capacity test of 1:1 equal ratio pillar under different constraint forms and different filling medium conditions was carried out. The results show that the binding pillar-forming effect is relatively good. The constraint ability of unconstrained, metal mesh, polyester mesh, hooked iron flat-hoop bushing, bellows, and spiral iron pipe is enhanced, in turn, and the carrying capacity is improved successfully. The homogeneity of high-water materials is better than concrete, and they have better compressibility, but their carrying capacity is relatively weak. The carrying capacity of concrete pillars is generously higher than that of high-water materials, but the compressibility is poor. Second, the migration characteristics of the surrounding rock structure of the gob-side entry retaining and the rule of side support are analyzed, the requirements of the side support are pointed out, and the side-support technology of the binding pillar is proposed. Taking Hijiata Mine’s 50108 working face gob-side entry retaining as an example, the bellows pump-filled concrete pillar is used as the side support body, supplemented by handling steel mesh and air-duct cloth, and toughness material is sprayed between the pillars to seal the goaf, meeting the requirements of side support and road stability. The pillar has the characteristics of high early strength, strong final consolidation carrying capacity, good crimping effect, high mechanism degree, fast construction speed, less concrete consumption, low comprehensive cost, etc., and it has a good application prospect in the gob-side entry retaining or rapid advanced working face. Full article

Background: Microorganisms are important regulators of soil phosphorus cycling and phosphorus availability in Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) plantations. However, the effects of thinning on soil phosphorus cycling by microbes in C. lanceolata plantations remain unclear. Methods: We performed a metagenomic sequencing analysis to investigate how thinning intensities (weak, moderate, and heavy) alter phosphorus cycling related microbial genes and their regulatory effects on soil phosphorus availability in C. lanceolata plantations. Results: Following heavy thinning, the contents of available and labile phosphorus increased by 13.8% and 36.9%, respectively, compared to moderate and weak thinning. Moreover, the relative abundance of genes associated with inorganic phosphorus solubilization increased significantly with the increase in thinning intensity, whereas genes associated with phosphorus uptake and transport significantly decreased. The metagenomic analysis results indicate that Acidobacteria (47.6%–53.5%), Proteobacteria (17.9%–19.1%), and Actinobacteria (11.7%–12.8%) are the major contributors to the functional phosphorus cycling genes in the soil. The random forest analysis results suggested that gcd, plc, phoN, ugpA, and phoR were the critical genes involved in the transformation and use of phosphorus, which in turn increased soil phosphorus availability. Structural equation modeling revealed that soil pH was the primary factor influencing changes in functional genes associated with phosphorus cycling in C. lanceolata plantations. Specifically, soil pH (ranging from 4.3 to 4.9) were positively correlated with genes involved in inorganic phosphate solubilization and organic phosphate mineralization, while negatively correlated with genes related to phosphorus uptake and transport. Conclusions: Taken together, our results demonstrate that the enhanced microbe-mediated mineralization of organic phosphorus and solubilization of inorganic phosphorus are suppressed when uptake and transportation are the mechanisms responsible for the increased soil phosphorus availability under appropriate thinning intensities. Changes in the soil microbial community and phosphorus cycling genes in response to different thinning intensities may maintain soil functionality and nutrient balance in C. lanceolata plantations. These findings contribute to a better understanding of the mechanisms underlying the microbial mediation of phosphorus cycling in the soil of C. lanceolata plantations. Full article

Agrobacterium (Rhizobium)-mediated transformation leads to the formation of crown galls or hairy roots on infected plants. These effects develop due to the activity of T-DNA genes, gathered on a big plasmid, acquired from agrobacteria during horizontal gene transfer. However, a lot of plant species are known to contain such sequences, called cellular T-DNAs (cT-DNAs), and maintain normal phenotypes. Some of the genes remain intact, which leads to the conclusion of their functional role in plants. In this study, we present a comprehensive analysis of the cT-DNAs in the Nicotiana noctiflora Hook. genome, including gene expression and opine identification. Deep sequencing of the Nicotiana noctiflora genome revealed the presence of two different cT-DNAs, NnT-DNA1 and NnT-DNA2, which contain the intact genes iaaM, iaaH, acs, orf13, orf13a, and orf14. According to the expression analysis results, all these genes are most active in roots in comparison with other organs, which is consistent with data on cT-DNA gene expression in other plant species. We also used genetic engineering approaches and HPTLC and HPLC-MS methods to investigate the product of the acs gene (agrocinopine synthase), which turned out to be similar to agrocinopine A. Overall, this study expands our knowledge of cT-DNAs in plants and brings us closer to understanding their possible functions. Further research of cT-DNAs in different species and their functional implications could contribute to advancements in plant genetics and potentially unveil novel traits with practical applications in agriculture and other fields. Full article

Flapping Wing Air Vehicles (FWAVs) have proven to be attractive alternatives to fixed wing and rotary air vehicles at low speeds because of their bio-inspired ability to hover and maneuver. However, in the past, they have not been able to reach their full potential due to limitations in wing control and payload capacity, which also has limited endurance. Many previous FWAVs used a single actuator that couples and synchronizes motions of the wings to flap both wings, resulting in only variable rate flapping control at a constant amplitude. Independent wing control is achieved using two servo actuators that enable wing motions for FWAVs by programming positions and velocities to achieve desired wing shapes and associated aerodynamic forces. However, having two actuators integrated into the flying platform significantly increases its weight and makes it more challenging to achieve flight than a single actuator. This article presents a retrospective overview of five different designs from the “Robo Raven” family based on our previously published work. The first FWAVs utilize two servo motors to achieve independent wing control. The basic platform is capable of successfully performing dives, flips, and button hook turns, which demonstrates the potential maneuverability afforded by the independently actuated and controlled wings. Subsequent designs in the Robo Raven family were able to use multifunctional wings to harvest solar energy to overcome limitations on endurance, use on-board decision-making capabilities to perform maneuvers autonomously, and use mixed-mode propulsion to increase payload capacity by exploiting the benefits of fixed and flapping wing flight. This article elucidates how each successive version of the Robo Raven platform built upon the findings from previous generations. The Robo Raven family collectively addresses requirements related to control autonomy, energy autonomy, and maneuverability. We conclude this article by identifying new opportunities for research in avian-scale flapping wing aerial vehicles. Full article

The traditional method of taxiing for civil aircraft, which relies on their engines, may be surpassed by the new method of towing taxi-out due to its superior advantages such as reduced energy consumption, lower emissions, and higher efficiency. However, the towing taxi-out system poses a challenge to lateral stability due to the concentration of mass at the rear, leading to severe instability when turning at high speeds. To address this issue, a nonlinear civil aircraft towing and taxiing system model and a linear four-degree-of-freedom civil aircraft towing and taxiing system reference model were established using TruckSim and Matlab/Simulink software. The fuzzy proportional–integral–derivative controller was utilized, with the braking torque of each wheel serving as the control variable and the real-time yaw rate difference and its rate of change as the fuzzy control input. The controller was compared and validated with a traditional PID controller. The results of the simulation showed that the fuzzy PID control has better nonlinear characteristics and stronger adaptability to operating conditions compared to traditional PID control, providing timely, effective, adaptive, and robust control effects for the vehicle dynamics model. Under the fuzzy PID control, the peak yaw speed of the civil aircraft decreased to 10 degrees per second under double-shift conditions, representing an increase of 23.1%. Furthermore, the lateral stability and safety of the towing taxi-out system were improved, as evidenced by the reduction in the yaw rate of the tractor and civil aircraft under the hook condition. The use of this controller provides valuable technical guidance and support for the practical development and safe application of the towed glide mode. Full article

This paper is devoted to the fastening system that consists of a number of anchors of approximately equal effective embedment depth, called “anchor group”, embedded into hardened concrete, used to transmit forces transverse to the anchors from an attachment to the concrete. The anchor group is far from the edges and is subjected to no more than marginal axial forces. Being post-installed, rather than cast-in, the embedded end of each anchor is not hooked, and no nuts, washers, or plates are attached to the embedded shaft. The paper focuses on the transverse forces that can be transmitted across an anchor group from an attachment to the concrete. The paper provides an analytical model for predicting the maximum (ultimate) shear force that an anchor group can bear, thus called “shear strength”. The model hence allows the structural designer to predict the shear strength of an anchor group post-installed into concrete. The model is based on five mechanical assumptions, which were established from a wide-ranging numerical analysis. Model predictions turned out to be, on average, 20% lower than the results of experiments performed on cast-in anchor groups borrowed from literature. The comparison verifies model accuracy, considering that the tested anchor groups benefitted from the extra-strength furnished by nuts and washers attached to the embedded shaft. Model predictions were also compared to code provisions; the former resulted to be up to one third of the latter. The paper presents and comments those comparisons, as well as all mathematical development. Applications of the model to wide-ranging case studies is presented and discussed as well. Full article

Auxin has been shown to exhibit a striking concentration gradient distribution in radial sections of angiosperm and gymnosperm species, in which peak auxin levels are concentrated in dividing cambial cells, while the absolute auxin concentration sharply declines toward developing secondary phloem and xylem regions. The coincidence of auxin concentration gradient across shoot tissues and xylem cell developmental gradient has prompted that auxin could act as “a plant morphogen” to provide a positional signal for cambial cell development. However, the specific location of vascular cambium and the lack of mutants altering auxin distribution in shoots of woody species made further verification experiments difficult to explore. To address this issue, different concentrations of exogenous IAA were applied to decapitated Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) trunks in this study to induce the change in the auxin concentration gradient in radial stems, and its effects on cambial activities were examined on the physiological, cellular and molecular levels. Our findings manifested that exogenous IAA treatments resulted in vast changes in endogenous hormone concentrations (including IAA, ZR, GA₃ and ABA), cambial cell developmental behaviors and transcriptional activities of genes related to polar auxin transport (PAT), auxin signaling, the biosynthesis and signal transduction of other plant hormones and the genetic control of cambial activity. Based on above findings, we postulated a model of auxin concentration gradient involved in the control of cambial activity and secondary growth in tree trunks. In this model, the contrasting expression of AUX1/LAX and PIN family carriers in distinct Chinese fir wood-forming tissues dynamically modulates PAT into the cambial zone adjacent to the secondary phloem side and secondary xylem tissues, resulting in a sharp and wide auxin spatial gradient distribution across shoots in different stages of secondary growth, respectively. This change in auxin concentration gradient distribution in radial sections in turn acts on cambial developmental behaviors by modulating the expression of auxin signaling genes and key transcription factors and the production of other plant hormones in distinct woody tissues. Findings in this study provide important insights for understanding the biological significance of auxin concentration gradient existing in the radial stems of woody species. Full article

For crushable calcareous sand, the stress-dilatancy curve has a significant turning hook around the peak stress ratio, the hook contains the main features of the loading process, including the phase transformation point and the peak stress ratio point. However, more than half of this turning hook, i.e., the line after the peak stress ratio point, is usually ignored by known stress-dilatancy models. It is difficult to directly establish the stress-dilatancy model with such turning hook characteristics, since such turning hook demonstrates that the dilatancy is not a single-valued function of the stress ratio. Based on the first law of thermodynamic, we related dilatancy to breakage energy. Then, we mapped breakage energy from the stress-energy plane to the strain-energy plane to avoid the non-single-valued function problem. Then, the stress-dilatancy model was conveniently established. Compared with the other four existing stress-dilatancy models, the benefit of our modeling process is that it can easily capture the turning hook of the stress-dilatancy curve. Our model is also verified by simulating colloidal-silica-stabilized and MICP-stabilized calcareous sands, as well as three types of calcareous sands, respectively. Full article