Element Stress Research Articles

Relevance of monitoring residual stresses and the need to reduce them

The objective of the study is to show the significant impact of taking into account the actual values of residual stresses on the strength and resource of safe operation of nuclear power facilities. Generally accepted approaches of strength physics and fracture mechanics were used to determine strength and service life. The degree of influence of residual stresses on the strength and service life of pipeline elements in the case of a cyclically acting load, under static load, when there is a danger of brittle fracture, and in the case of corrosion is investigated. The objects of the study were pipelines of nuclear power plants. It is noted that the current state of science and technology has made it possible to create a technique for non-destructive testing of mechanical stresses acting in metal structures based on the use of the acoustoelasticity method. Currently, on the basis of this method, a method for measuring residual welding and installation stresses in pipelines has been developed and certified for use in the field of atomic energy use. The measurement technique provides for the determination of membrane and bending stresses in annular sections located on rectilinear sections of pipelines. The values of stresses in the structural elements of pipelines and residual welding stresses in the deposited metal of welded joints are determined using ratios based on the use of the balancing principle. The relevance of introducing into the procedure for monitoring the technical condition of pipelines and equipment of nuclear power plants the procedure for determining the actual level of residual stresses, which significantly increases the reliability of the assessment of their strength and service life, is shown. It is proved that in order to implement the procedure for determining the actual level of residual stresses, it is necessary to use a non-destructive testing system for residual welding and installation stresses using the acoustoelasticity method based on a measurement technique that allows determining the actual values of residual stresses with established error characteristics.

Spider diversity (Arachnida: Araneae) at Saurashtra University Campus, Rajkot, Gujarat during the monsoon

The present work deals with the diversity of spiders during the monsoon within the Saurashtra University Campus, Rajkot, Gujarat. A total of 38 species of spiders belonging to 32 genera and 14 families were recorded. Araneidae (25.81%) was found to be the most dominant family, with nine species from five genera. Guild structure analysis revealed seven feeding guilds, among all 31% most dominant feeding guilds represented by orb-web builders and stalkers, followed by ground runners (13%), irregular webs (10%), ambushers (7%), foliage hunters (6%), and space-web builders (2%). Ecological indices reveal high species richness (Margalef’s d = 8.97) and diversity (Shannon Index H’ = 3.526, Fisher alpha diversity α = 41.73). It concludes that the abundance of spider species at this study site was high and the evenness index was also high (e >0, e = 0.8944). These findings suggest the absence of stress elements in the study area.

Evaluating Angled Abutments: Three-Dimensional Finite Element Stress Analysis of Anterior Maxillary Implants

Restorative dentistry is the repairing of damaged teeth and restoring oral health and function. Dental implants are typically placed within the cortical bone of the jaw to provide stability and support for prosthetic restorations. The successful restoration of complex anatomical features of the maxillary anterior is difficult for prosthodontists. Using a 3D slicer, CT scan images were used to create a detailed three-dimensional model of the maxilla bone. This study utilizes ANSYS Workbench, a finite element software program, to analyze the abutment angles, ranging from 0° to 25°, and the impact stress distribution within peri-implant bone. The outcomes of our studies align with and substantiate certain evidence in the literature documenting bone resorption, specifically at the level of the implant neck and near the cortical bone. The study aims to provide a comprehensive understanding of angled abutment stress patterns in the bone surrounding dental implants, offering valuable insights for clinical applications in critical areas of the mouth.

Fractographic justification of fracture resistance loss in steel elements of overloaded machinery metal constructions

The problem related to the loss of resistance to brittle fracture in steel elements of the metal structure of loading equipment has been investigated. A fracto- graphic analysis was conducted at macro and micro levels on samples taken from two sections of the crane that underwent testing to determine their impact toughness. The selected samples covered the least and most loaded areas of the crane's metal structure to reflect the minimum and maximum levels of operational steel degradation. The assessment of metal degradation was carried out based on its resistance to brittle fracture. A correlation was established between the nature of the fracture, energy absorption, and indicators of resistance to brittle fracture. Special attention was given to the location of delamination along the direction of rolling during macro and microfracto- graphic studies. Macrofractographic analysis confirmed the general tendency of the metal to delaminate, especially along the fibers of the texture. This tendency varied for different sections of the crane's metal structure and depended on the level of operational stresses in the structural elements. It was found that longitudinal samples exhibited fractographic signs of delamination in the form of secondary cracks perpendicular to the fracture plane. The macrofracture of a sample from a loaded area revealed a significant amount of delamination, indicating their role in the propagation of fractures during impact tests. These results allow establishing a connection between the material's structure, its mechanical properties, and operational degra-dation, which is crucial for improving the reliability and safety of crane metal structures

Coupling strength comparison in optical fiber with multiple sector shape stress elements

AbstractThe maximum stress oscillation amplitude and maximum coupling strength of the optical fiber with multiple sector stress elements are studied. Optimized fiber structure with craft feasible is designed and the related structural parameters are given. Comparing the research results, it is found that the optical fiber with triple sector stress elements can achieve the strongest coupling strength to realize the single circular polarization state conversion by the shortest coupling distance. In addition, though the maximum coupling strength is decreased as the number of stress elements increases, it remains the same order of magnitude as the triple sector's. So from the craft perspective, whether it is an optical fiber with triple sector stress elements or the other optical fiber with more sector stress elements, the optical fiber with the property of single circular polarization transmission can be achieved if the spinning rate satisfies the phase matching condition.

Quantitative prediction of surrounding rock deformation via an energy-based damage model combining with microseismic monitoring

In this study, combined with microseismic (MS) monitoring and numerical simulation, a novel energy-based damage model is proposed for quantitatively predicting the surrounding rock deformation for the stability analysis of underground engineering. First, the rock damage range is delineated based on MS event location and source radius. Second, seismic efficiency is introduced to calculate the actual released energy, and the total releasable energy density and total stored energy density are derived from element stress information and stress–strain curves in numerical simulation. Finally, a novel energy-based damage model with definite physical significance is developed based on the above-mentioned three forms of energy. Our new model introduces MS source parameters into the classical damage variable based on dissipated energy, accurately reflecting the qualitative relationship between them, which is highly applicable to practical engineering. Moreover, this model comprehensively reflects the damage degree variation of surrounding rocks from in-situ stress state to different excavation stages and describes real-time deterioration of rock mechanical parameters. In addition, a new approach based on seismology formulation is applied to solve seismic efficiency, without requiring reference to the destruction situation. To validate our proposed model, a three-dimensional (3D) numerical simulation embedding the damage model is conducted to investigate the surrounding rock deformation behavior of underground caverns in the Lianghekou hydropower station. A reasonable consistency is observed between the simulated displacement field and source parameters distribution obtained from MS monitoring and field failure. Furthermore, compared to the original model without a damage variable, the energy-based damage model greatly improves the deformation prediction precision.

Degradation of RC Columns under Combined Exposure to Axial Loading, Stray Currents, and Chloride Ingress.

Coastal regions, home to a significant portion of the world's population, confront a formidable challenge: the corrosive impact of chloride-rich environments on vital infrastructure. These areas often host essential transportation systems, such as trains and metros, reliant on pre-existing electrical infrastructure. Unfortunately, complete isolation of this infrastructure is rarely feasible, resulting in the emergence of stray currents and electrical potentials that expedite corrosion processes. When coupled with conducive mediums facilitating chemical electrocell formation, the corrosion of reinforced concrete elements accelerates significantly. To combat this issue, international standards have been established, primarily focusing on augmenting the thickness of reinforcement bar covers and restricting stray voltage between rails and the ground. Nevertheless, these measures only provide partial solutions. When subjected to service loads, these elements develop cracks, especially when exposed to stray currents and chlorides, dramatically increasing corrosion rates. Corrosion products, which expand in volume compared to steel, exert internal forces that widen cracks, hastening the deterioration of structural elements. The study deals with the degradation of reinforced concrete columns under the combined action of loads, chloride-rich environments, and electrical voltage-simulating stray currents. In these conditions, degradation and reduction of load-bearing capacity accelerate compared to unloaded conditions, significantly amplifying the corrosion rate. Astonishingly, even in the absence of mechanical loads, stray currents alone induce tensile stresses in elements due to corrosion product formation, leading to longitudinal cracks parallel to the reinforcement bars.

Elements of Minority Stress and Resilience in LGBTQ+ Students’ Experience of Education

ABSTRACT This study investigates the experiences of minority stress and resilience among LGBTQ+ students in educational settings and identifies critical contributors to their well-being. To highlight the unique educational experiences of LGBTQ+ participants a qualitative research strategy was employed. We conducted narrative interviews with 27 LGBTQ+ people aged 17 to 41 who are or have been enrolled in primary, secondary or tertiary education in Slovenia. The results indicate that minority stress is a significant in their educational experiences, with various deleterious effects. The testimonies of our respondents indicate, albeit to a lesser extent, that the education system can enhance the resilience of LGBTQ+ youth and mitigate the negative impacts of minority stress. This study confirms prior research on minority stress effects on LGBTQ+ individuals. It asserts that LGBTQ+ youth experience minority stress within the education system, while emphasizing that certain aspects of resilience can significantly mitigate these negative effects. As social support emerged as a significant factor in our study, it would be reasonable to investigate how school personnel can enhance LGBT youths’ resilience in the future. Additionally, it would be beneficial to investigate how the support of peers and (chosen) families influences the school experiences of LGBTQ+ students.

Obtaining a jaw model from computed tomography data for studying and predicting the mechanical stress of the implant system elements under conditions close to the real one

This article deals with the creation of a three-dimensional model of the cancellous bone-cortical bone-implant-abutment-screw system. This model allows predicting the mechanical stress of the implantation system elements under conditions close to the real one. Such visualisation helps to determine the stress coefficients and to determine the places of presumed mechanical loading of the future implantation bed.

Harnessing multimodal wrinkle patterns in flexible films by three-axial mechanical loading

Controllable wrinkle structures have great application prospects in the fields of flexible electronics, smart sensing, elastic optics, surface wetting, and bio-interfaces. In flexible film-substrate systems, strain actuation is capable of obtaining various wrinkle patterns with single morphological features including labyrinths, herringbones, stripes, hierarchies and ordered arrays. However, it is still a big challenge to obtain multiple wrinkle patterns on a surface of film simultaneously. Here, we propose a facile method for preparing controllable multimode wrinkles by exerting three-axial compression. The morphological features of the wrinkles show a universal position-dependent behavior for different flexible film systems. From a corner of the triangular film sample to the opposite edge, the wrinkles evolve from striped structure to labyrinth-like structure and finally to rippled structure gradually. The finite element simulation and stress theory well explain the formation mechanism and evolution behavior of the multimode wrinkles observed in experiments. The surface friction and light diffraction are strongly dependent on the wrinkle features and show excellent reversibility and stability by cyclic mechanical loading. This work can promote better understanding of stress distribution and wrinkling mechanism under three-axial mechanical loading, and can develop a novel technique for preparing controllable multiple, position-dependent wrinkle patterns.

Design and Research on the Mechanical Structure of a Heavy-Duty Hexapod Robot with Bouncing Characteristics

Based on the lunar exploration project, a mechanical structure design scheme for a heavy-duty hexapod robot movement system with bounce characteristics was proposed. The materials used were determined by the robot's working environment and performance standards. The mechanical structure of a jumping heavy-duty hexapod robot was designed using SolidWorks 3D modeling software. Based on the analysis of the working modes of the root joint, hip joint, knee joint, and jumping energy storage mechanism, the main components of each joint and jumping energy storage mechanism were designed, and a single leg mechanism was obtained. Based on the special soil structure on the lunar surface, the foot end buffer mechanism was designed, and finite element stress analysis was conducted on the key components of the robot model, proving the rationality of the mechanical structure of a heavy-duty hexapod robot with bounce characteristics.

Over-Denture Attachment Systems: Systematic Review with Meta-Analysis

Current scientific growths for implant over-denture attachments. We focused on the following topics: attachment systems, retention of various attachments, stress distribution with different attachments, the design and fabrication of attachments, digital techniques in over denture attachments, and the effects of attachments in two-implant health. We found that plastic resin is commonly used for ball and bar attachments, whereas nylon resin is commonly used in locator attachments. The locator system offers a valuable attachment option for implant-retained over denture. Attachment retention reduces while lateral force increases with implant inclination in over denture. The higher the retention of an over-denture attachment, the higher the transferred stresses. Additionally, clip loading produces more stress in implants and precision elements than bar-retained dentures.

Unconventional cyclic plasticity model implementation for shell and plane stress elements in UMAT/Abaqus

Finite element simulations are widely used in several industrial sectors (civil, aerospace, mechanical, naval, biomedical, etc.) to design components or structures. Often, the resolution of highly non-linear problems requires the recurse to dense meshes with the consequent increase in computation time. This aspect becomes particularly relevant for cyclic mobility problems where repeated loading might affect the computational cost. Therefore, the efficiency of finite elements represents a crucial aspect of speeding up the design process. Past works of the authors focused on developing the additive hypoelastic-based and multiplicative hyperelastic-based constitutive equations of the Extended Subloading Surface model for three-dimensional finite elements adopting fully implicit integration schemes. In this paper, the constitutive equations of the Extended Subloading Surface theory are reformulated for shell and plane stress elements, aiming to obtain an efficient computational tool suitable for cyclic mobility problems. The numerical implementation considers isotropic hardening, kinematic hardening, and material anisotropy. Numerical solutions obtained utilising shell/plane stress and solids elements are also discussed.

Systematic analysis and expression of Gossypium ATG8 family reveals the roles of GhATG8f responding to salt stress in cotton.

Comprehensive analysis of Gossypium ATG8 family indicates that GhATG8f could improve salt tolerance of cotton by increasing SOD, POD and CAT activity and proline accumulation. In plants, autophagy is regulated by several genes that play important roles in initiating and controlling the process. ATG8, functioning as a protein similar to ubiquitin, is involved in crucial tasks throughout the autophagosome formation process. In this research, we conducted an extensive and all-encompassing investigation of 64 ATG8 genes across four varieties of cotton. According to the subcellular localization prediction results, 49 genes were found in the cytoplasm, 6 genes in the chloroplast, 1 gene in the peroxisome, 5 genes in the nucleus, and 3 genes in the extracellular region. Phylogenetic analysis categorized a total of 5 subfamilies containing sixty-four ATG8 genes. The expression of the majority of GhATG8 genes was induced by salt, drought, cold, and heat stresses, as revealed by RNA-seq and real-time PCR. Analysis of cis-elements in the promoters of GhATG8 genes revealed the predominant presence of responsive elements for plant hormones and abiotic stress, suggesting that GhATG8 genes might have significant functions in abiotic stress response. Furthermore, we additionally performed a gene interaction network analysis for the GhATG8 proteins. The salt stress resistance of cotton was reduced due to the downregulation of GhATG8f expression, resulting in decreased activity of CAT, SOD, and POD enzymes, as well as decreased fresh weight and proline accumulation. In summary, our research is the initial exploration of ATG8 gene components in cotton, providing a basis for future investigations into the regulatory mechanisms of ATG8 genes in autophagy and their response to abiotic stress.

Beowulf 1563a and Blissian Metrics

A. J. Bliss, in his authoritative and influential monograph on The Metre of Beowulf (1967), analysed l. 1563a, hē ġefēng þā fetelhilt, as a member of his group (4) of verses beginning with finite verbs. In verses of that group, in which the verb is the last particle before the first stressed element, alliterating finite verbs are thought to be an integral part of the alliterative scheme of the line and hence to be metrically stressed. This means that, according to Bliss, l. 1563a is a Type 1A2a with hē and ġe- in anacrusis. This analysis is compatible with Bliss’s definition of anacrusis, according to which any two unstressed syllables can be in the extrametrical prelude to a verse. As this essay shows, however, personal pronouns are not normally found in anacrustic positions in the poem, and so it appears reasonable to believe that seemingly anacrustic hē is not part of the authorial reading, but a result of scribal misapprehension of the text in the exemplar. After considering several possibilities and solutions, this article proposes cancellation of hē on the grounds that the scribe found the absence of a pronominal subject at that point confusing, and so decided to supply one to make the syntax of the passage closer to the syntax of late Old English verse. Emendation to ġefēng þā fetelhilt does not change Bliss’s analysis of l. 1563a as a Type 1A2a, but it does mean that that verse should be considered a member not of group (4), but of group (3): the verb is the only particle before the first stressed element. The essay concludes by reminding readers of Bliss’s monograph that his definition of anacrusis can be accepted as long as pronouns and linguistic elements other than verbal prefixes and proclitic ne are excluded from the definition.

Biomechanical Evaluation of 2 Endoscopic Spine Surgery Methods for Treating Lumbar Disc Herniation: A Finite Element Study.

This study aimed to evaluate the effects of 2 endoscopic spine surgeries on the biomechanical properties of normal and osteoporotic spines. Based on computed tomography images of a healthy adult volunteer, 6 finite element models were created. After validating the normal intact model, a concentrated force of 400 N and a moment of 7.5 Nm were exerted on the upper surface of L3 to simulate 6 physiological activities of the spine. Five types of indices were used to assess the biomechanical properties of the 6 models, range of motion (ROM), maximum displacement value, intervertebral disc stress, maximum stress value, and articular protrusion stress, and by combining them with finite element stress cloud. In normal and osteoporotic spines, there was no meaningful change in ROM or disc stress in the 2 surgical models for the 6 motion states. Model N1 (osteoporotic percutaneous transforaminal endoscopic discectomy model) showed a decrease in maximum displacement value of 20.28% in right lateral bending. Model M2 (unilateral biportal endoscopic model) increased maximum displacement values of 16.88% and 17.82% during left and right lateral bending, respectively. The maximum stress value of L4-5 increased by 11.72% for model M2 during left rotation. In addition, using the same surgical approach, ROM, maximum displacement values, disc stress, and maximum stress values were more significant in the osteoporotic model than in the normal model. In both normal and osteoporotic spines, both surgical approaches were less disruptive to the physiologic structure of the spine. Furthermore, using the same endoscopic spine surgery, normal spine biomechanical properties are superior to osteoporotic spines.

Identification and expression analysis of TCP family members in tobacco (Nicotiana tabacum L.)

TCP family as plant specific transcription factor, plays an important role in different aspects of plant development. In order to screen TCP family members in tobacco, the homologous sequences of tobacco and Arabidopsis TCP family were identified by genome-wide homologous alignment. The physicochemical properties, phylogenetic relationships and cis-acting elements were analyzed by bioinformatics. The homologous genes of AtTCP3/AtTCP4 were screened, and RT-qPCR was used to detect the changes of gene expression upon 20% PEG6000 treatment. The results show that tobacco contains 63 TCP family members. Their amino acid sequence length ranged from 89 aa to 596 aa, and their protein hydropathicity grand average of hydropathicity (GRAVY) ranged from -1.147 to 0.125. The isoelectric point (pI) ranges from 4.42 to 9.94, the number of introns is 0 to 3, and the subcellular location is all located in the nucleus. The results of conserved domain and phylogenetic relationship analysis showed that the tobacco TCP family can be divided into PCF, CIN and CYC/TB1 subfamilies, and each subfamily has a stable sequence. The results of cis-acting elements in gene promoter region showed that TCP family genes contain low docile acting elements (LTR) and a variety of stress and metabolic regulation related elements (MYB, MYC). Analysis of gene expression patterns showed that AtTCP3/AtTCP4 homologous genes (NtTCP6, NtTCP28, NtTCP30, NtTCP33, NtTCP42, NtTCP57, NtTCP63) accounted for 20% PEG6000 treatment significantly up-regulated/down-regulated expression, and NtTCP30 and NtTCP57 genes were selected as candidate genes in response to drought. The results of this study analyzed the TCP family in the tobacco genome and provided candidate genes for the study of drought-resistance gene function and variety breeding in tobacco.

Genome-wide analysis of transmembrane 9 superfamily genes in wheat (Triticum aestivum) and their expression in the roots under nitrogen limitation and Bacillus amyloliquefaciens PDR1 treatment conditions.

Transmembrane 9 superfamily (TM9SF) proteins play significant roles in plant physiology. However, these proteins are poorly characterized in wheat (Triticum aestivum). The present study aimed at the genome-wide analysis of putative wheat TM9SF (TraesTM9SF) proteins and their potential involvement in response to nitrogen limitation and Bacillus amyloliquefaciens PDR1 treatments. TraesTM9SF genes were retrieved from the wheat genome, and their physiochemical properties, alignment, phylogenetic, motif structure, cis-regulatory element, synteny, protein-protein interaction (PPI), and transcription factor (TF) prediction analyses were performed. Transcriptome sequencing and quantitative real-time polymerase reaction (qRT-PCR) were performed to detect gene expression in roots under single or combined treatments with nitrogen limitation and B. amyloliquefaciens PDR1. Forty-seven TraesTM9SF genes were identified in the wheat genome, highlighting the significance of these genes in wheat. TraesTM9SF genes were absent on some wheat chromosomes and were unevenly distributed on the other chromosomes, indicating that potential regulatory functions and evolutionary events may have shaped the TraesTM9SF gene family. Fifty-four cis-regulatory elements, including light-response, hormone response, biotic/abiotic stress, and development cis-regulatory elements, were present in the TraesTM9SF promoter regions. No duplication of TraesTM9SF genes in the wheat genome was recorded, and 177 TFs were predicted to target the 47 TraesTM9SF genes in a complex regulatory network. These findings offer valued data for predicting the putative functions of uncharacterized TM9SF genes. Moreover, transcriptome analysis and validation by qRT-PCR indicated that the TraesTM9SF genes are expressed in the root system of wheat and are potentially involved in the response of this plant to single or combined treatments with nitrogen limitation and B. amyloliquefaciens PDR1, suggesting their functional roles in plant growth, development, and stress responses. These findings may be vital in further investigation of the function and biological applications of TM9SF genes in wheat.

Comparative Genome Analysis of Polar Mesorhizobium sp. PAMC28654 to Gain Insight into Tolerance to Salinity and Trace Element Stress.

In this study, Mesorhizobium sp. PAMC28654 was isolated from a soil sample collected from the polar region of Uganda. Whole-genome sequencing and comparative genomics were performed to better understand the genomic features necessary for Mesorhizobium sp. PAMC28654 to survive and thrive in extreme conditions and stresses. Additionally, diverse sequence analysis tools were employed for genomic investigation. The results of the analysis were then validated using wet-lab experiments. Genome analysis showed trace elements' resistant proteins (CopC, CopD, CzcD, and Acr3), exopolysaccharide (EPS)-producing proteins (ExoF and ExoQ), and nitrogen metabolic proteins (NarG, NarH, and NarI). The strain was positive for nitrate reduction. It was tolerant to 100 mM NaCl at 15 °C and 25 °C temperatures and resistant to multiple trace elements (up to 1 mM CuSO4·5H2O, 2 mM CoCl2·6H2O, 1 mM ZnSO4·7H2O, 0.05 mM Cd(NO3)2·4H2O, and 100 mM Na2HAsO4·7H2O at 15 °C and 0.25 mM CuSO4·5H2O, 2 mM CoCl2·6H2O, 0.5 mM ZnSO4·7H2O, 0.01 mM Cd(NO3)2·4H2O, and 100 mM Na2HAsO4·7H2O at 25 °C). This research contributes to our understanding of bacteria's ability to survive abiotic stresses. The isolated strain can be a potential candidate for implementation for environmental and agricultural purposes.

Lily LlHSFC2 coordinates with HSFAs to balance heat stress response and improve thermotolerance.

Heat stress transcription factors (HSFs) are core regulators of plant heat stress response. Much research has focused on class A and B HSFs, leaving those of class C relatively understudied. Here, we reported a lily (Lilium longiflorum) heat-inducible HSFC2 homology involved in thermotolerance. LlHSFC2 was located in the nucleus and cytoplasm and exhibited a repression ability by binding heat stress element. Overexpression of LlHSFC2 in Arabidopsis, tobacco (Nicotiana benthamiana), and lily, all increased the thermotolerance. Conversely, silencing of LlHSFC2 in lily reduced its thermotolerance. LlHSFC2 could interact with itself, or interact with LlHSFA1, LlHSFA2, LlHSFA3A, and LlHSFA3B of lily, AtHSFA1e and AtHSFA2 of Arabidopsis, and NbHSFA2 of tobacco. LlHSFC2 interacted with HSFAs to accelerate their transactivation ability and act as a transcriptional coactivator. Notably, compared with the separate LlHSFA3A overexpression, co-overexpression of LlHSFC2/LlHSFA3A further enhanced thermotolerance of transgenic plants. In addition, after suffering HS, the homologous interaction of LlHSFC2 was repressed, but its heterologous interaction with the heat-inducible HSFAs was promoted, enabling it to exert its co-activation effect for thermotolerance establishment and maintenance. Taken together, we identified that LlHSFC2 plays an active role in the general balance and maintenance of heat stress response by cooperating with HSFAs, and provided an important candidate for the enhanced thermotolerance breeding of crops and horticulture plants.