Ontogeny Research Articles

Investigating organophosphorus pesticides in dates from Khesht City (Iran): Impact of washing and assessment of the health risks

Dates are rich in nutrients, making them popular all over the world as healthy fruits. Due to the use of pesticides by gardeners to control pests in date palm farms, date fruits may contain pesticides, which could potentially endanger the health of consumers. In this study, date fruit samples at three different growth stages (green fruit, unripe date, date) were collected from the groves of Khesht city. The residues of 15 organophosphorus pesticides in water-washed and unwashed samples were measured using gas chromatography-mass spectrometry (GC–MS). The results showed that the residue levels of all organophosphorus pesticides measured were below the maximum residue limits recommended by FAO and CODEX. Based on the data, washing date fruits with water can effectively reduce the residual amount of organophosphorus pesticides, thereby helping to reduce the intake of pesticides. Moreover, the results of the risk assessment showed that consumption of unripe and ripe dates from Khesht has no carcinogenic (<10–6) or non-carcinogenic (HI<1) effects on adults. However, Future studies should analyze the soil and irrigation water of palm groves for organophosphorus pesticide contamination. Increasing gardeners' awareness of pesticide risks to human health is crucial for responsible pesticide use in horticulture.

Changes in DNA repair compartments and cohesin loss promote DNA damage accumulation in aged oocytes.

Oocyte loss, a natural process that accelerates as women approach their mid-30s, poses a significant challenge to female reproduction. Recent studies have identified DNA damage as a primary contributor to oocyte loss, but the mechanisms underlying DNA damage accumulation remain unclear. Here, we show that aged oocytes have a lower DNA repair capacity and reduced mobility of DNA damage sites compared to young oocytes. Incomplete DNA repair in aged oocytes results in defective chromosome integrity and partitioning, thereby compromising oocyte quality. We found that DNA repair proteins are arranged in spatially distinct DNA repair compartments that form during the late stages of oocyte growth, accompanied by changes in the activity of DNA repair pathways. We demonstrate alterations in these compartments with age, including substantial changes in the levels of key DNA repair proteins and a shift toward error-prone DNA repair pathways. In addition, we show that reduced cohesin levels make aged oocytes more vulnerable to persistent DNA damage and cause changes in DNA repair compartments. Our study links DNA damage accumulation in aged oocytes, a leading cause of oocyte loss, to cohesin deterioration and changes in the organization, abundance, and response of DNA repair machinery.

Does emission trading system (ETS) deserve further promotion in the building sector? Evidence from China

Although the emission trading system (ETS) has been widely applied and recognized in energy-production side, its impact on the energy-demand side is still ambiguous. Does ETS deserve promotion in energy-demand sectors? If so, what preparations are necessary? In response to these pressing but highly publicized issues, this paper, for the first time, focuses on the building sector which is the most typical energy-demand sector based on energy consumption data from public buildings across 26 regions in China spanning 12 years by employing the Synthetic Control Method (SCM). China, as the most representative developing country with more than ten years of ETS pilot practice for buildings, is a good evidence base. The results indicate that ETS has overall applicability to the building sector despite regional variations. And the government support, industrial structure and economic development orientation are the most determinant of its effect, rather than the conventionally perceived heterogeneous sectoral characteristics of buildings. Moreover, for buildings in the stage of rigid growth, the ETS should be adopted first and foremost to reduce its carbon intensity rather than the total amount. The findings provide practical recommendations on whether and how to promote ETS in future buildings, particularly in developing countries.

Shock-driven three-fluid mixing with various chevron interface configurations

When a shock wave crosses a density interface, the Richtmyer–Meshkov instability causes perturbations to grow. Richtmyer–Meshkov instabilities arise from the deposition of vorticity from the misaligned density and pressure gradients at the shock front. In many engineering applications, microscopic surface roughness will grow into multi-mode perturbations, inducing mixing between the fluid on either side of an initial interface. Applications often have multiple interfaces, some of which are close enough to interact in the later stages of instability growth. In this study, we numerically investigate the mixing of a three-layer system with periodic zigzag (or chevron) interfaces, calculating the dependence of the width and mass of mixed material on properties such as the shock timing, chevron amplitude, multi-mode perturbation spectrum, density ratio, and shock mach number. The multi-mode case is also compared with a single-mode perturbation. The Flash hydrodynamic code is used to solve the Euler equations in three dimensions with adaptive grid refinement. Key results include a significant increase in mixed mass when changing from a single-mode to a multi-mode perturbation on one of the interfaces. The mixed width is mainly sensitive to the density ratio and chevron amplitude, whereas the mixed mass also depends on the multi-mode spectrum. Steeper initial perturbation spectra have lower mixed mass at early times but a greater mixed mass after the reflected shock transits back across the layer.

The evolution of micro-photoluminescence spectra of PECVD diamond microcrystals along the vertical growth direction and their dependence on CH4 concentration

The changes in the shape of micro-photoluminescence spectra of PECVD diamond micro-crystal measured, depending on the position of the excitation laser spot along the crystallite height, were analyzed. It was ascertained that the processes of SiV defect formation non-monotonically depend on the distance from the Si substrate. At the distances of 2–20 μm the concentration of SiV defects increases, then at distances larger than 20 μm the number of SiV defects decreases. The concentration of NV− and NV0 defects monotonically increases with the distance from the Si substrate. The predomination of SiV defect formation at the beginning stages of the crystal growth is explained by the substantial concentration of carbon vacancies required for their formation. With the increase in the distance from the substrate, the crystalline perfection increases, the concentration of carbon vacancies decreases and the processes of NV− and NV0 defect formation dominate. The increase in CH4 fraction within 0.75–6 % leads to the increase in the volume fraction of graphite-like carbon, which is the good diffusion channel for Si atoms from the substrate into the plasma. Therefore, the concentration of SiV, NV−, and NV0 defects on the surface of the crystal depends on the volume fraction of graphite-like carbon defined by CH4 content.

Probing early phase coarsening in a rapidly quenched Bose gas using off-resonant matter-wave interferometry

We experimentally investigate the evolution of spatial phase correlations in a rapidly quenched inhomogeneous Bose gas of rubidium using off-resonant matter-wave interferometry. We measure the phase coherence length ℓ of the sample and directly probe its increase during the early stage of condensate growth before vortices are formed. Once the vortices are formed stably in the quenched condensate, the measured value of ℓ is shown to be linearly proportional to the mean distance between the vortex. These results confirm the presence of phase coarsening prior to vortex formation, which is crucial for a quantitative understanding of the resultant defect density in samples undergoing critical phase transitions. Published by the American Physical Society 2024

Metabolic and bariatric surgery for obstructive sleep apnoea syndrome: bibliometric analysis and visualisation from 1999 to 2023

ObjectivesMetabolic and bariatric surgery (MBS) for obstructive sleep apnoea syndrome (OSAS) has garnered significant research interest. The main aim of this study was to analyse the unique characteristics of publications...

Positive impact of large wild herbivore exclusion on silver fir regeneration: A case study from the Poľana Mountains, Central Slovakia

Abstract In forest ecosystems, the browsing activity of large wild herbivores (LWH) often leads to reduced tree and plant diversity, diminished biomass production, and challenges in achieving forest management objectives. Our case study focuses on assessing the impact of LWH browsing during the initial stages of forest growth by comparing fenced plots (F plots) with excluded LWH and control plots (C plots) with the presence of LWH. The experiment took place at the Hukavský Grúň research site in the Poľana Mts., characterized by a high red deer (Cervus elaphus L.) population. Fifteen F plots and fifteen C plots, all situated within mixed maternal forests, were established in the 2023 growing season. Thus, circular plots with a radius of 2.5 m were utilized, and comprehensive data were collected on young trees (excluding those under 10 cm in height), covering tree species, positions, heights, and stem diameters. Species-specific allometric relations were employed to calculate the aboveground biomass of each tree, contributing to the overall biomass stock on a plot basis. A comparison between F and C plots revealed a prevalence of silver fir (Abies alba Mill.) in F plots, while European beech (Fagus sylvatica L.) dominated C plots. F plots exhibited higher tree species diversity (4.5 species), contrasting with the lower diversity (2.0 species) and absence of silver fir in C plots. The F plots also demonstrated greater tree density and sizes, resulting in substantial differences in aboveground biomass stocks. Browsing in C plots predominantly affected tree height rather than stem diameter, leading to a bigger height-to-diameter ratio in F plots compared to C plots. We suggest that fencing as a method to exclude LWH might be economically expensive and provide a temporary solution limited by the functionality of the fence. Therefore, the primary strategy for safeguarding the future of silver fir may lie in regulating LWH populations to a reasonable threshold.

Proline Priming Enhances Seed Vigour and Biochemical Attributes of Rice (Oryza sativa L.) during Germination.

Seed vigour is a desirable trait especially for direct seeded rice (DSR) cultivation. Seeds with high vigour could improve seed germination, support seedlings in competing with weeds for water and nutrients, and improving seedling establishment throughout the early stages of crop growth. The success of DSR system which account for more 25% of world cultivation areas is highly dependent on the seed vigour and seedling establishment. Seed priming is a promising technique to improve seed vigour. Proline is an amino acid that has been well studied for its roles in plants under different environmental stress conditions. Nevertheless, the effect of proline as a seed priming agent in improving seed vigour in rice remain elusive. In this research, the effect of 24 h of proline priming at various concentrations (0 mM, 1 mM, 2 mM, 10 mM and 20 mM) on rice seed vigour, amylase activity, and total soluble sugar (TSS) content of a Malaysia indica rice variety, MR269 was investigated. Results showed that seeds primed with lower concentration of proline (0 mM, 1 mM and 2 mM) had better germination responses while priming at high concentrations (10 mM and 20 mM) reduced seed germination. Among the concentration tested, priming with 1 mM proline enhanced seed vigour with significantly higher germination percentage (GP), germination rate index (GRI) and seedling vigour index (SVI). In addition, proline primed seeds also exhibited increased amylase activity and TSS content as compared to unprimed seeds. However, priming seed with 20 mM proline was detrimental to the seed vigour and seedling growth whereby lower GP, GRI and SVI and higher mean germination time (MGT) were observed. In short, this study shows that proline could be a potential seed priming agent to improve seed vigour in rice.

X-Band Radar and Surface-Based Observations of Cold-Season Precipitation in Western Colorado’s Complex Terrain

Abstract Hydrologic processes associated with intermountain cold-season precipitation in the Upper Colorado River basin have important impacts on avalanche forecasting and water resource management. However, traditional weather radar networks struggle with observations in this complex terrain. Data collected during the Study of Precipitation, the Lower Atmosphere, and the Surface for Hydrometeorology (SPLASH) and its sister campaign, Surface Atmosphere Integrated Field Laboratory (SAIL) in the East River watershed of western Colorado, are used to examine a multistorm period from 23 December 2021 to 1 January 2022 that contributed 35% of the total winter precipitation in this watershed. Dual-polarization X-band radar and disdrometer measurements show ∼30-mm differences in precipitation amount at two sites in proximity over four distinct storm events within the period. Wind patterns, synoptic forcings, microphysical characteristics of precipitation, and surface meteorology are analyzed to explain the observed spatial variability of cold-season precipitation in complex mountainous terrain. Analysis shows that differences over time within this event are mainly accounted for by synoptic forcings, such as frontal passages; differences between sites are accounted for by the impact of variations in local wind patterns on precipitation microphysics. Patterns of surface precipitation intensity are compared and found to be correlated with X-band radar signatures; a relationship between a strong dendritic growth stage and intense low-density surface precipitation is reinforced by this study. This relationship demonstrates the importance of particle growth mechanisms on surface snowfall patterns in high-altitude complex terrain, underscoring the importance of realistic microphysical parameterizations. Significance Statement The amount and density of snowpack from western Colorado winter storms have significant impacts on water resources in the Upper Colorado River basin. Snowpack characteristics are affected by small-scale differences in how snow forms in the atmosphere. These differences are hard to study in the complex terrain of the Rockies, but data from the SPLASH and SAIL field campaigns allows us to investigate how snow crystal formation and mountain-driven wind patterns affect snow near the surface. Our study finds that snow crystal growth varies over small space and time scales and is likely controlled by the terrain beneath a given location and resultant local wind patterns. These results imply that predicting snowpack in the Rockies requires properly representing local wind patterns and crystal growth processes in models.

Long-term investigation of the irrigation intervals and supplementary irrigation strategies effects on winter wheat in the U.S. Central High Plains based on a combination of crop modeling and field studies

Implementing optimized irrigation strategies to achieve acceptable wheat yield while conserving groundwater resources is critical for extensively irrigated regions. Field experiments regarding winter wheat irrigation management were conducted for two growing seasons (2013–2014 and 2014–2015) to calibrate and validate the AquaCrop model. To determine proper parameterization of the AquaCrop model for various data availability conditions, the model performance was tested for calibration based on three different datasets, including a) calibration based on a full irrigation condition (CA 1), b) calibration based on a dryland condition (CA 2), and c) calibration based on diverse irrigation conditions, which included full irrigation, different deficit irrigation levels, and dryland (CA 3). The CA 3 calibration scenario resulted in the model's highest accuracy in simulating biomass, grain yield, total soil water, and seasonal evapotranspiration during the calibration and validation process. However, the model performance was also convenient when calibration based on full irrigation conditions was pursued. The calibrated and validated AquaCrop model based on the CA3 was used to analyze long-term (36-year) irrigation management scenarios for identifying the optimized water-conservative winter wheat irrigation strategies. The long-term analysis emphasized that increasing irrigation intervals from 7 to 15 or 20 days could reduce groundwater withdrawal by 52–64 % while expecting a 14–19 % reduction in grain yield. By implementing one 25 mm irrigation after planting and two 25 mm depth irrigation events at jointing or leaf growth stages, 91 % of Kansas's average winter wheat yield (2.88 tons/ha) could be achieved. During wet years, the 1.2 ton/ha reduction in biomass and 0.27–0.62 ton/ha reduction in grain yield is expected irrespective of irrigation management strategies. Considerable uncertainty was detected in grain yield production during dry years under dryland (rainfed) conditions. The maximum winter wheat production could be achieved under normal years, establishing a balance between precipitation and heat units. Our agro-hydrological analysis revealed that the highest irrigation water use efficiency could be attained by the application of two 25 mm irrigation events at jointing or flag leaf growth stages during normal years, the application of two irrigation events during jointing or heading during wet years, and two 25 mm irrigations at heading or flowering during dry years. The results of this research could be used as a baseline for producers of the U.S. Central High Plains and semi-arid regions with similar climate characteristics to cope with water scarcity in winter wheat production.

Experimental study on fluid-Induced vibration caused by backward erosion piping based on acoustic emission

Abstract Double-layer dike foundation is one of the most common stratum types with the highest probability of catastrophic failure in dike engineering, and the most important danger is backward erosion piping. The occurrence and development of piping need to be monitored by reliable technology. Therefore, the influence of different piping outlet forms on acoustic emission monitoring is explored by using a self-designed test device. The results show that the overall evolution process of ringing count and accumulated energy can be divided into two stages according to the time of piping. In the first and middle stages, the particle collision is caused by sand boiling at the outlet, and the measured value is small. In the later stage, piping channels appear, particle migration occurs, and the measured value is large. Moreover, the maximum impact value decreases with the increase of the piping outlet, and the cumulative energy growth rate of the three groups of tests in the early stage is the same, while the head difference required for the rapid growth stage is inversely proportional to the piping outlet.

Understanding the fouling characteristics in ultrafiltration membrane for marine algae-laden seawater pretreatment: Focus on the role of algal extracellular organic matter

The increasing frequency and extent of harmful algal blooms (HABs) due to global warming and environmental pollution pose significant challenges to the ultrafiltration (UF)-seawater reverse osmosis (SWRO) desalination process. The UF process is a dominant pretreatment method to reduce HAB fouling potential in subsequent SWRO processes. Herein, we systematically evaluate the UF membrane fouling characteristics at different growth phases of HAB algae in terms of reversible/irreversible fouling and pinpoint the fouling mechanisms on UF membranes in the real seawater matrix. We employed Prorocentrum donghaiense as a model marine HAB specie to characterize algal derivatives, including extracellular organic matter (EOM) and granule particles. LC-OCD, MFIs, 3D-EEM, and GPC were used to analyze algae-derived matters. Results from the multiple fouling model revealed that algal solution in both stationary and decline phases exhibit severe membrane fouling, characterized by rapid cake layer formation, swift flux decline, and high membrane resistance. Soluble EOM (S-EOM) was the primary contributor to membrane fouling, linked to its elevated concentrations of dissolved organic matters, polysaccharides, proteins, and humic substances, which are predominantly hydrophobic. Additionally, granule particles mitigated organic membrane fouling, as evidenced by the smaller permeate volume required for S-EOM cake layer formation (<5 mL), resulting in a faster initial flux decline. These results revealed a shift in released organic matter from protein-centric to humic substance-centric during the transition from exponential growth to the decline phase, with correlation analysis further underscoring the substantial contribution of humic substances to membrane resistance. This research highlights the distinct UF membrane fouling characteristics at different marine algal growth stages, offering theoretical support for predicting and managing HABs.

Nuclear DNA Markers to Distinguish between Salix caprea, Salix gracilistyla, and Their Interspecific Hybrids

The Salix genus of the Salicaceae family has advantages such as rapid initial growth, a high germination rate, and asexual reproduction; therefore, it is used as a short-rotation energy crop for biomass production. The National Institute of Forest Science created new interspecific hybrid cultivars with superior biomass production by artificially interbreeding Salix caprea L. and Salix gracilistyla Miq. Identifying these hybrids during the seedling stage is challenging because their separate reproductive and vegetative growth stages necessitate prolonged observation of their morphological characteristics. Consequently, a reliable identification method is required to overcome these limitations. This study aimed to develop nuclear DNA markers to distinguish between S. caprea, S. gracilistyla, and their interspecific hybrids. An evaluation of 35 nuclear simple-sequence repeat (nSSR) markers in the Salix genus revealed two markers that distinguish these parent species and their hybrids. A sequence analysis confirmed the presence of insertion-deletion (InDel) regions within the nSSR markers that differed between S. caprea and S. gracilistyla. To effectively identify hybrids, a primer set comprising the InDel region, which exhibited only interspecies differences and no intraspecies differences, was developed. The results of this study will facilitate the genetic resource management of interspecific hybrids between S. caprea and S. gracilistyla, thus allowing for early identification and improved management of hybrids.

Associations Between Developmental Stability, Canalization, and Phenotypic Plasticity in Response to Heterogeneous Experience.

The processes of developmental stability, canalization, and phenotypic plasticity have ecological and evolutionary significance, and been studied extensively, but mostly separately and thus the relationships between them are not straightforward. Our objective was to better integrate these processes in the context of temporally heterogeneous environments. We did this by investigating the effects of early experience with temporal heterogeneity in water availability on associations between developmental stability, canalization, and phenotypic plasticity. We subjected eight plant species to a first round of alternating inundation and drought vs. constantly moderate water treatments (heterogeneous experience) and a second round of water conditions (to test plasticity). We measured fluctuating asymmetry (FA) in leaf size, intra- and inter-individual variation (CVintra and CVinter), and plasticity (PI) in traits and analyzed correlations between these variables across all species. Results showed little correlations between FA, CVintra and PI, several positive correlations between FA and CVinter in more stressful conditions, especially in as well as positive correlations between CVinter and PI initially and negative correlations between them later. These suggested the complexity of these relationships, which can depend on whether plasticity occurs. Greater inter-individual variation will more likely cooperate with plasticity before or during plastic response, whereas higher canalization may reflect phenotypic convergence. Both higher FA and CVintra can reflect faster growth, while CVintra may also reflect plant growth stage, and the two mechanisms should cooperate in response to environmental challenges. The complexity of these relationships suggests plants deal with environmental variation in elaborate and integrative ways which can be affected by many factors.

Characterization of key aroma compounds in microgreens and mature plants of hydroponic fennel (Foeniculum vulgare Mill.)

Fennel is a popular culinary herb known for its unique flavor. In this study, we identified key aroma-active compounds in fresh fennel (Foeniculum vulgare Mill.) and its microgreens. Fennel was cultivated hydroponically with soilless substrates. Upon harvesting, samples were ground with liquid nitrogen, and headspace solid phase microextraction (SPME) gas chromatography-mass-spectrometry-olfactometry (GC-MS-O) was used for volatile analysis. Thirty-two and 28 key aroma-active compounds were identified in fennel microgreens and mature leaves, respectively. Phenylpropenes, especially (E)-anethole, were the predominant aroma-active compound in all samples (36.3–83.4 %). Quantitation results showed that fennel microgreens contained a significantly higher amount of monoterpenes, showing an 81.4–98.1 % increase when compared to mature fennel. Principal component analysis (PCA) of identified volatiles indicated a distinctive difference in the overall aroma profile between microgreens and mature leaf. The changes in aroma contents over different growth stages revealed the underlying volatile biosynthesis discrepancy. This study provided baseline information for understanding the aroma evolution from microgreen to mature fennel herbs

Prospects and Application of Solid-State Fermentation in Animal Feed Production – A Review

Abstract Animal feed production has recently received significant attention in the food and livestock sectors due to its high nutritional value and substantial environmental potential. Extensive studies have been conducted to explore the effects of solid fermented feeds on different growth stages of animals but also on the health status of animals, the quality of animal products, and the composition of intestinal micro-flora to replace non-fermented feed production. The purpose of this review is to provide up-to-date existing trends, recent developments, and prospects of solid-state fermentation (SSF) practices for the production of animal feeds. Studies on enhancing nutritional factors by increasing the crude protein content, enzymes, and antioxidant activity of feed using physical processing methods on agro-industrial waste such as rapeseed meal, cottonseed, wheat bran, soybean meal, and legumes by mainly SSF are reviewed and discussed thoroughly.

Effects of carbon nanoparticle insertion on stress reduction in hydrogenated amorphous carbon films using plasma chemical vapor deposition

Stress reduction in hydrogenated amorphous carbon (a-C:H) films is of considerable interest for improving their performance as protective films. Herein, we reduced the compressive stress of the films by inserting carbon nanoparticles (CNPs) between two a-C:H layers to form an a-C:H/CNP/a-C:H sandwich structure using a system of plasma chemical vapor deposition (CVD). We measured the deposition features of the CNPs via transmission electron microscopy (TEM) and assessed the dependence of the stress on the thickness of the second a-C:H layer as a parameter of surface coverage, Cp. We represented the stress reduction as a function of Cp; mean size of large CNPs, and thickness of the first and second a-C:H layers. In addition, the surface and film morphologies were investigated using atomic force microscopy (AFM) and cross-sectional scanning electron microscopy (SEM). Compared with films without CNPs, those containing CNPs with 8.9 % Cp showed 36 % lower stress when the thickness of the second a-C:H layer was similar to that of the first (154 nm). The deposited CNPs exhibited two size groups, with mean sizes of the small and large CNPs of 5 and 16 nm, respectively. Stress reduction was strongly correlated with the distance between large CNPs. The insertion of CNPs between a-C:H films affects the surface morphology of the second layer, and the stress decreases when the growth stage of the film starts transitioning from three-dimensional (3D) to two-dimensional (2D).

Evaluation of the Aggregation Efficiency Modeling at Colder Atmospheric Temperatures in Comparison to Satellite Observations

Abstract Aggregation efficiency in the upper troposphere is highly uncertain because of the lack of laboratory experiments and aircraft measurements, especially at atmospheric temperatures below −30°C. Aggregation is physically broken down into collision and sticking. In this study, theory-based parameterizations for the collision efficiency and sticking efficiency are newly implemented into a double-moment bulk cloud microphysics scheme. Satellite observations of the global ice cloud distribution are used to evaluate the aggregation efficiency modeling. Sensitivity experiments of 9-day global simulations using a high-resolution climate model show that the use of collision efficiency parameterization causes a slight increase in the cloud ice amount above the freezing level over the tropics to midlatitudes and that the use of our new sticking efficiency parameterization causes a significant increase in the cloud ice amount and a slight decrease in the snow amount particularly in the upper troposphere over the tropics. The increase/decrease in the cloud ice/snow amount in the upper troposphere over the tropics is consistent with the vertical profile of radar echoes. Moreover, the ice fraction of the cloud optical thickness is still underestimated worldwide. Finally, the cloud radiative forcing increases over the tropics to reduce the bias in the radiation budget. These results indicate that our new aggregation efficiency modeling reasonably functions even at atmospheric temperatures below −30°C; however, further improvements in the ice cloud modeling are needed. Significance Statement Long-standing biases in the radiative budget in climate models indicate the existence of a missing mechanism to realistically represent the ice cloud growth in the upper troposphere. This study focuses on aggregation efficiency, which has been assumed to be a tuning parameter to optimize the global radiative budget. Therefore, this study employs a theory-based parameterization to calculate the aggregation efficiency. According to the parameterization, aggregation efficiency in high clouds varies by the growth stage of the individual ice particles. As a result, small ice crystals are likely to grow more slowly, and the lifetime of cirrus clouds is prolonged to enhance cloud radiative forcing, particularly over the tropics. These results are promising for reducing the biases observed in climate models.

Optimization of a Boom Height Ultrasonic Detecting Model for the Whole Growth Cycle of Wheat: Affected by the Oscillation of the Three-Section Boom of the Sprayer

In the dynamic operation of a boom sprayer, the boom oscillation will cause the detection value of the boom height to fluctuate greatly, resulting in failures of the control system. Based on the previously developed static boom height detection model for the entire wheat growth cycle, this study aimed to optimize the model to reduce the impact of boom oscillation on the accuracy of boom height detection. Three ultrasonic sensors were installed on each section boom of a three-section boom sprayer, and dynamic boom height detection tests were conducted at vehicle speeds of 4 to 8 km/h across six growth stages of winter wheat in Beijing, a total detection area within a single fixed operational row of approximately 14 ha. The test results showed that as vehicle speed increased, boom oscillations intensified across all sections. By setting the boom oscillation correction parameters, the detecting value of each section of boom height is corrected. The results show that the fluctuation and deviation degree of the boom height-detecting value are obviously reduced, and the correction effect is obvious. Further analysis of the detecting value of the boom height after the correction shows that the previously established detection model still maintains high detection accuracy under dynamic conditions; that is, the detection position of the ultrasonic sensor does not downward shift. This paper provides a low-cost technical method that can be directly applied to the dynamic detection of boom height.