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A methodology to predict key aspects of the structural response of masonry walls under blast loading using artificial neural networks (ANN) is presented in this paper. The failure patterns of masonry walls due to in and out-of-plane loading are complex due to the potential opening and sliding of the mortar joint interfaces between the masonry stones. To capture this response, advanced computational models can be developed requiring a significant amount of resources and computational effort. The article uses an advanced non-linear finite element model to capture the failure response of masonry walls under blast loads, introducing unilateral contact-friction laws between stones and damage mechanics laws for the stones. Parametric finite simulations are automatically conducted using commercial finite element software linked with MATLAB R2019a and Python. A dataset is then created and used to train an artificial neural network. The trained neural network is able to predict the out-of-plane response of the masonry wall for random properties of the blast load (standoff distance and weight). The results indicate that the accuracy of the proposed framework is satisfactory. A comparison of the computational time needed for a single finite element simulation and for a prediction of the out-of-plane response of the wall by the trained neural network highlights the benefits of the proposed machine learning approach in terms of computational time and resources. Therefore, the proposed approach can be used to substitute time consuming explicit dynamic finite element simulations and used as a reliable tool in the fast prediction of the masonry response under blast actions. [ABSTRACT FROM AUTHOR]

This article presents an experimental and numerical study of the collapse behavior of a 60‐m‐high cement silo structure under blast loading, analyzed using SAP2000 (FEM‐NDA) and LS‐DYNA (FEM‐NDA‐explicit code) models to simulate the collapse mechanism. Considering the seismic events in Kahramanmaras, Turkiye, on February 6, 2023, with magnitudes of 7.8 and 7.6, the necessity for the explosive demolition of hundreds of thousands of structures has underscored the urgency of rapid planning. This situation requires a particular focus on the expeditious analysis of demolition methodologies. The study includes pre‐planning stages, sudden column removals and the detonation of columns with blast loads for the controlled demolition of a full‐scale existing silo structure. To overturn the structure, the columns inside the wedge region were suddenly removed using SAP2000 nonlinear dynamic analysis (NDA) to understand the subsequent load redistribution. A study was conducted to compare the use of shell and plate elements in SAP2000 for a 1‐m‐thick wall silo. The results showed that using shell elements provided relatively closer results to real values than plate elements. For the explicit analysis part, the structural components were modeled as solid materials, and columns were detonated with blast loads. The models and actual demolition frame‐by‐frame results of the structure were compared, and the numerical model's accuracy was validated using experimental data from stationary cameras and drones, with the explicit analysis results found to be in agreement. While explicit analysis yielded results more in line with real data, SAP2000 NDA provided relatively distant results, although SAP2000‐NDA was more time‐efficient compared to explicit analysis models. However, a preliminary evaluation can be made if the characteristics of both programs are understood. The documented information on full‐scale structure demolition and findings presented in this paper will serve as a resource for future studies and provide a reference for researchers. [ABSTRACT FROM AUTHOR]

• A new peridynamic model is presented to study the explosive blast effects on solids. • Failure behaviors of steel and aluminum plates are investigated in explosions. • A parametric study is conducted to examine the impact of different blast parameters. • New guidelines are proposed to enhance the explosive blast resistance of solid plates. The paper presents a novel and efficient model to examine deformations and fractures in solid plates when exposed to explosive blast events under various scenarios and boundary conditions. The proposed model uses the peridynamic method to simulate the motion and damage of solid plate particles during explosions in a mesh-free scheme. The model's validation with experimental results is essential to ensure that the proposed model can capture the actual behavior of solid plates in explosive blasts. The present study shows the following novelties: (1) A novel coupling strategy is presented, which integrates explosive blast loadings with the peridynamic method. Therefore, the model becomes capable of effectively capturing the interactions between explosive blasts and solid plates; (2) The proposed model demonstrates remarkable stability in modeling explosive blasts on solid plates, and it does not require refinement schemes nor adaptive modeling parameters such as adaptive timestep; (3) The peridynamic model overcomes the mesh-distortion issues commonly encountered in mesh-based models, particularly under extreme loading conditions; (4) The proposed model exhibits high efficiency, enabling fast and accurate simulations of solid plate behavior under explosive blast scenarios. The paper also presents a new parametric study that explores the failure behavior of solid plates during explosions. [ABSTRACT FROM AUTHOR]

The growing threat of accidental and malevolent blast loading to building structures has necessitated the consideration of blast-resistant design. Columns are the most vulnerable and critical component of a building, so they must be designed against blast to achieve defined performance goals. The influence of transverse rebar detailing on the ultimate capacity and failure modes of rectangular reinforced concrete (RC) columns against blast loads was investigated under different detonation scenarios. The performance of the columns was quantified using the failure charge mass and post-blast residual axial capacity. Pressure–impulse diagrams were used to study the failure modes. The analyses showed that special transverse detailing measures were the most effective for columns subjected to near-field surface bursts. The confinement of concrete due to ties and axial restraint played a critical role in improving the blast performance of columns. The provision of diagonal rebar improved the blast resistance by preventing direct shear failure, and was most effective when coupled with closely spaced lateral ties. Finally, the performance of code-compliant columns against blast was studied to determine the blast safety margin and the scenarios under which it would be necessary to undertake blast retrofitting of the columns in existing critical buildings. [ABSTRACT FROM AUTHOR]

Bacterial Leaf Blight (Xanthomonas oryzae pv. oryzae) and blast (Magnaporthe oryzae) are the major biotic stresses around the rice-growing zones of the world. The development of resistant varieties through Marker Assisted Backcross Breeding is the utmost economical and eco-friendly method for achieving stable yield. Amongst the resistance genes recognized, Xa21 and Pi54 possess broad-spectrum resistance to many Xoo and blast strains around the world. In the present study, we have effectively introgressed a Bacterial Blight resistance gene (Xa21) and a blast resistance gene (Pi54) into susceptible variety ADT43 from RP-Bio-Patho-2 coupled with phenotypic selection for agronomic, cooking quality and grain traits through MABC. MABC was sustained till BC2F2 generation with specific markers pTA248 for Xa21 and Pi54MAS for Pi54 resistance genes. A set of SSR markers for parental polymorphism were utilized for maximum regaining of recurrent parent genome in each backcrossing. "Positive plants" from BC2F1 were selfed to generate BC2F2 and the homozygous lines for bacterial leaf blight and blast resistance genes were identified for further assessment. [ABSTRACT FROM AUTHOR]

Large-scale flank collapses are one of the main hazards associated with the evolution of volcanic islands. Precisely dating such events is critical to evaluate the frequency of destabilization episodes and further assess the triggering mechanism(s) associated with internal and/or external factors, such as volcano dynamics, regional tectonics, and global paleoclimatic changes. Here, we constrain the age of a pumice-rich pyroclastic deposit exposed on the eastern flank of Flores Island (Azores), which we interpret as a co-blast deposit generated by a major flank collapse that destroyed the whole western flank of the former volcanic edifice. Twelve single-grain 40Ar/39Ar analyses, performed on 250–500 µm anorthoclase feldspars (mean K/Ca close to 5) with our high-sensitivity multi-collector NGX mass spectrometer, provide a robust weighted mean age of 1.32 ± 0.01 Ma for this eruption. This new age is consistent with previous K/Ar data bracketing the flank collapse between 1.30 ± 0.04 and 1.18 ± 0.09 Ma, and indicates that this event occurred at the end of the main construction phase of the volcano. The explosion produced pumice-rich layers preceded by a lahar as attested by a polygenetic mudflow deposit underlying the dated deposit. From the geochemistry of lavas erupted just before and after the collapse, we speculate upon the possible role of magmatic processes on flank destabilization. We propose a first hypothesis where differentiation in a shallow magma reservoir could have favored edifice inflation, ground shaking, and flank failure, triggering a decompression-induced violent eruption. Overall, our study shows that high-sensitivity mass spectrometers have now reached analytical performances allowing to measure precisely and accurately ages on relatively small and moderately K-rich single feldspars, which is of the utmost importance for dating heterogeneous blasts and tephra deposits that may have been induced by large-scale flank collapses during the late Quaternary. [ABSTRACT FROM AUTHOR]

Background: The family Geminiviridae contains plant viruses commonly referred to as geminiviruses, which cause diseases in numerous important plants. Geminiviridae is one of the most important family of plant-infecting viruses that has been divided into fourteen recognized genera. Amongst these, the genus Begomovirus is the largest and economically most important one, viruses of the genus are further categorized into bipartite (two genomic components called DNA-A and DNA-B) and monopartite (single genomic component or DNA-A) begomoviruses. Method: The genomic DNA was extracted from symptomatic plant samples and both the DNA-(B and A) components of a bipartite begomovirus were amplified via rolling circular amplification (RCA) and PCR. The amplified DNA-A and DNA-B were cloned and sequenced by Primer walking, Sanger sequencing, and Illumina sequencing methods. The phylogenetic and biogeographic analyses of both components were performed by various bioinformatics tools. Results: DNA-A (accession number MW722701) and DNA-B (accession number MW722782) of begomoviruses that were sequenced shared >95% sequence similarity with the bipartite begomovirus known as Tomato Leaf Curl New Delhi virus (TLCuNDV). Phylogenetic and biogeographic analyses proposed several possible ancestors, and multiple dispersal and vicariance events may be involved in the evolution of this virus. Conclusions: This is the first time a bipartite begomovirus has been found to infect a plant in the study area (District Swat, Pakistan). The existence of ToLCNDV may pose a major danger to other important crops in the region. [ABSTRACT FROM AUTHOR]

Introduction: Although traumatic brain injury (TBI) has been linked with adverse long-term health, less research has examined whether TBI is linked with nonclinical outcomes including involuntary job loss. Symptoms associated with TBI may influence one’s ability to maintain gainful employment including employment in the U.S. military. That influence may impact military service members with exposure to repetitive low-level blast (LLB). Understanding the association between TBI and involuntary job loss outcomes among military populations is particularly important as it may be associated with differences in eligibility for post-service benefits. The purpose of the present research was to determine whether (1) TBI and related conditions are associated with involuntary job loss (i.e., medical and administrative separations from service) among military personnel, and (2) occupational risk of LLB is associated with involuntary job loss in both the presence and absence of clinical diagnoses of TBI and related conditions. Method: This research leveraged population-level data from the Career History Archival Medical and Personnel System for enlisted personnel who served on active duty between 2005–2015. Risk of LLB exposure was categorized using military occupational specialty as a proxy. Medical diagnoses were identified using ICD-9 codes. Separations for medical and administrative reasons were identified. Results: Risk for administrative separation differed across medical diagnoses of interest, but those who worked in high-risk occupations were more likely to be administratively separated than those working in low-risk occupations. Risk for medical separation was associated with occupational risk of LLB and each of the diagnoses of interest, though significant interactions suggested that the effects of certain diagnoses of interest (e.g., concussion, cognitive problems, postconcussive syndrome, migraines) on medical separations was greater among those working in high-risk occupations. Discussion: Taken together, the present research suggests that TBI and associated medical conditions, as well as occupational risk of LLB, are associated with long-term involuntary job loss for medical reasons. This study is the first to demonstrate involuntary military job loss outcomes associated with TBI, mental health conditions, and conditions associated with blast exposure using both inpatient and outpatient population-level data and may have important implications for civilian employment and post-service benefits. [ABSTRACT FROM AUTHOR]

This study investigated the evolutionary relationship between Aeolothrips collaris Priesner, 1919 and Aeolothrips intermedius Bagnall, 1934 within the Thysanoptera: Aeolothripidae family. Notably, A. collaris DNA barcode was made for the first time and compared with other Aeolothrips species in GenBank. While revealing a close genetic association (82-83%) between these species, the analysis using the Neighbor-Joining method clustered A. collaris with A. albicinctus Haliday, 1836 and A. ericae Bagnall, 1920, while A. albicinctus grouped alongside A. fasciatus (Linnaeus 1758) and A. duvali Moulton, 1927 GenBank BlastN analysis supported the expected placement of A. intermedius. These insights highlight significant genetic connections but suggest the necessity for a broader examination involving more species and gene regions. Expanding this research could yield a comprehensive understanding of the intricate taxonomic relationships within this thrips genus, setting the groundwork for future investigations into thrips species evolution and taxonomy. [ABSTRACT FROM AUTHOR]

Injuries and subclinical effects from exposure to blasts are of significant concern in military operational settings, including tactical training, and are associated with self-reported concussion-like symptomology and physiological changes such as increased intestinal permeability (IP), which was investigated in this study. Time-series gene expression and IP biomarker data were generated from "breachers" exposed to controlled, low-level explosive blast during training. Samples from 30 male participants at pre-, post-, and follow-up blast exposure the next day were assayed via RNA-seq and ELISA. A battery of symptom data was also collected at each of these time points that acutely showed elevated symptom reporting related to headache, concentration, dizziness, and taking longer to think, dissipating ~16 h following blast exposure. Evidence for bacterial translocation into circulation following blast exposure was detected by significant stepwise increase in microbial diversity (measured via alpha-diversity p = 0.049). Alterations in levels of IP protein biomarkers (i.e., Zonulin, LBP, Claudin-3, I-FABP) assessed in a subset of these participants (n = 23) further evidenced blast exposure associates with IP. The observed symptom profile was consistent with mild traumatic brain injury and was further associated with changes in bacterial translocation and intestinal permeability, suggesting that IP may be linked to a decrease in cognitive functioning. These preliminary findings show for the first time within real-world military operational settings that exposures to blast can contribute to IP. [ABSTRACT FROM AUTHOR]

The response of sandwich structures under the synergistic effects of blast wave and fragments is a topic of interest for researchers and designers. Thus, the performance of a sandwich structure used for enhancing the protection of a target structure is numerically investigated because it may experience such complex loading conditions resulting from combined blast and fragment impact. A conventional sandwich structure modelled using aluminium alloy resists a bare blast load imposed on it. Analysis, however, reveals that fragments penetrate through the front facesheet of a conventional sandwich structure, indicating a lower resistance of the front facesheet to combined blast and fragment effects. Thus, the behaviour of conventional aluminium honeycomb sandwich structures is compared with enhanced sandwich configurations consisting of a front facesheet covered with multilayer lightweight composite Kevlar fabric material. The Kevlar fabric arrests the maximum number of fragments, and reduces their momentum, thereby reducing the damage level in the sandwich structure. The effect of the charge weight and shape of the fragments on the damage modes of the sandwich structure is also assessed. With the increase in charge weight, the momentum of the fragments is found to increase, and these penetrate the back facesheet of the sandwich structure. [ABSTRACT FROM AUTHOR]

Due to the growing need for sustainable and ultra-high-strength construction materials, scientists have created an innovative ultra-high-performance concrete called Geopolymer based ultra-highperformance concrete (GUHPC). Besides, in the last few decades, there have been a lot of explosions and ballistic attacks around the world, which have killed many civilians and fighters in border areas. In this context, this article reviews the fresh state and mechanical properties of GUHPC. Firstly, the ingredients of GUHPC and fresh properties such as setting time and flowability are briefly covered. Secondly, the review of compressive strength, flexure strength, tensile strength and modulus of elasticity of fibrous GUHPC. Thirdly, the blast and projectile impact resistance performance was reviewed. Finally, the microstructural characteristics were reviewed using the scanning electron microscope and X-ray Powder Diffraction. The review outcome reveals that the mechanical properties were increased when 30% silica fume was added to a higher dose of steel fibre to improve the microstructure of GUHPC. It is hypothesized that the brittleness of GUHPC was mitigated by adding 1.5% steel fibre reinforcement, which played a role in the decrease of contact explosion cratering and spalling. Removing the need for cement in GUHPC was a key factor in the review, indicating a promising potential for lowering carbon emissions. However, GUHPC research is still in its early stages, so more study is required before its full potential can be utilized. [ABSTRACT FROM AUTHOR]

Pier columns, as primary bridge supports, are vulnerable to extreme loading demands resulting from fire, vehicle collisions, and blasts. The combined effects of these demands may cause significant strength reduction, extensive damage, and potentially collapse. Although the response of bridge columns subjected to independent or combined vehicle impact and air blast has been widely investigated, the cumulative effects of fire in conjunction with these dynamic loads have received limited attention. Consequently, this study presents a unique and advanced multistep finite-element modeling approach using LS-DYNA to simulate the response of isolated round reinforced concrete bridge columns subjected to fire prior to and after a vehicle collision and subsequent air blast. The developed modeling approach incorporates uncoupled implicit heat transfer analyses and explicit structural analyses and was validated against published fire, impact, and blast test results. A parametric study that investigated the effects of various column diameters and fire exposure scenarios on performance was completed, considering fire occurring before or after impact and blast. Column performance was assessed based on damage levels, residual load capacities, and lateral displacements. Study findings enhance the understanding of bridge column performance under this combination of hazards, provide insight into improving bridge resiliency, and could potentially have practical implications for the design and maintenance of bridge columns. Specifically, the study reveals that fire prior to impact and blast was a more critical load sequence for larger column diameters that could potentially remain in service in their final damage states while being repaired. Moreover, the study indicated that for the same fire duration and column diameters, residual capacities and displacements corresponding to half-surface-area exposure were slightly lower than those exposed to fire on the full surface area, a finding that could be beneficial in many practical applications where protective techniques and tools could be implemented. [ABSTRACT FROM AUTHOR]

Rice is one of the most important crops in the world and a staple food for more than half of the world's population. At present, the blast disease caused by the fungus Magnaporthe oryzae poses a severe threat to food security through reduction of rice yields worldwide. High phosphate fertilization has previously been shown to increase blast susceptibility. At present, however, our knowledge on the mechanisms underpinning phosphate-induced susceptibility to M. oryzae infection in rice is limited. In this work, we conducted live cell imaging on rice sheaths inoculated with a M. oryzae strain expressing two fluorescently-tagged M. oryzae effectors. We show that growing rice under high phosphate fertilization, and subsequent accumulation of phosphate in leaf sheaths, promotes invasive growth of M. oryzae. Consistent with this, stronger expression of M. oryzae effectors and Pathogenicity Mitogen-activated Protein Kinase (PMK1) occurs in leaf sheaths of rice plants grown under high a phosphate regime. Down-regulation of fungal genes encoding suppressors of plant cell death and up-regulation of plant cell death-inducing effectors also occurs in sheaths of phosphate over-accumulating rice plants. Treatment with high Pi causes alterations in the expression of fungal phosphate transporter genes potentially contributing to pathogen virulence. From the perspective of the plant, Pi accumulation in leaf sheaths prevents H2O2 accumulation early during M. oryzae infection which was associated to a weaker activation of Respiratory Burst Oxidase Homologs (RBOHs) genes involved in reactive oxygen species (ROS) production. Further, a weaker activation of defense-related genes occurs during infection in rice plants over-accumulating phosphate. From these results, it can be concluded that phosphate fertilization has an effect on the two interacting partners, pathogen and host. Phosphate-mediated stimulation of fungal effector genes (e.g., potentiation of fungal pathogenicity) in combination with repression of pathogen-inducible immune responses (e.g., ROS accumulation, defense gene expression) explains higher colonization by M. oryzae in rice tissues accumulating phosphate. Phosphate content can therefore be considered as an important factor in determining the outcome of the rice/M. oryzae interaction. As fertilizers and pesticides are commonly used in rice cultivation to maintain optimal yield and to prevent losses caused by pathogens, a better understanding of how phosphate impacts blast susceptibility is crucial for developing strategies to rationally optimize fertilizer and pesticide use in rice production. [ABSTRACT FROM AUTHOR]

Ridge gourd is cultivated in tropical, subtropical and few varieties like Pusa Nasdar and Satputia temperate regions across the world. It is a rich source of essential vitamins and minerals around the world. However, the production of ridge gourd has been severely affected by diseases among which viral diseases have major impact on its production. The viral disease caused by tomato leaf curl New Delhi virus (ToLCNDV), a member of the genus Begomovirus, family Geminiviridae-an economically important virus affecting the ridge gourd yield. It is transmitted by the whiteflies [Bemisia tabaci (Gennadius)] and causes ridge gourd yellow mosaic disease (RgYMD) in ridge gourds. The present study mainly aimed at the process of development of Agrobacterium coat protein gene construct and in silico analysis of CP. The total DNA from infected leaves of ridge gourd with ToLCNDV was amplified using CP specific primers with amplicon size of 771bp. The purified CP. gene was successfully cloned to the TA cloning vector. The CP gene was further moved into plant expression binary vector pBI121. The gene construct of the plant expression vector was transformed into Agrobacterium tumefaciens. In-silico analysis of the coat protein revealed that the protein contains nuclear export factors BR1 family. BLAST results analysis of coat protein with respect to the other coat proteins of ToLCNDV depicted 80-90 per cent resemblance. Phylogenetic tree revealed the common origin of this protein. [ABSTRACT FROM AUTHOR]