Temperature Stress Research Articles

Heat and mass transfer in tri‐layer ependymal ciliary transport with diverse viscosity

AbstractSpecialized cilia known as ependymal cilia help the cerebrospinal fluid, which is important for nutrient delivery and waste elimination, to circulate in the brain. Many species rely on cilia and flagella for fluid movement and motility. Cilia and flagella, for instance, produce propulsive forces that allow unicellular creatures like Paramecium and Euglena to move through their surroundings. Ciliary transport plays a role in the flow of egg cells, or oocytes, via the fallopian tubes in the female reproductive system. The transfer of the egg towards the uterus is facilitated by the synchronized wave‐like motion produced by the cilia lining the fallopian tubes. Like this, ciliary transport in men aids in the passage of sperm cells via the epididymis. Many scientists and researchers are studying the mechanics of cilia motion and the properties of the viscoelastic fluid layer to develop new treatments and applications in biomedical engineering and for some diseases. Motivated by a wide range of biological applications, the objective of this study is to investigate the heat and mass transfer flow of tri‐layered Newtonian fluids flowing with the help of ciliary beating in a Cartesian coordinate. The fluid is incompressible, and fluid layers are not intermixed. The fluid flow with heat and mass transfer is first modelled in wave and then transmuted into fixed. Solutions for temperature profile, velocity distribution, stresses and concentration distribution are obtained. The influence of incipient parameters is displayed with graphs and plotted with the computational software MATHEMATICA 13.0 in the results section. The key findings obtained from graphs show that the maximum magnitude for temperature and velocity is achieved in the middle layer of fluid whereas in the outer layer concentration profile is maximum. It is predicted that this approach will make an essential contribution to the progress and enhancement of various types of drug delivery systems in the biomedical industry and biomechanics.

PGPR alleviated the negative effects of low temperature and low light stress on the growth and physiology of violet plants

Plants in greenhouses are often exposed to low temperature and low light conditions in the winter, and this has a major effect on flower cultivation. Inoculation of plant growth-promoting rhizobacteria (PGPR) can improve the growth of plants under stress. Here, we examined the effects of Pseudomonas fluorescens on the growth, photosynthesis, chlorophyll fluorescence parameters, and antioxidant enzyme systems of violet plants (Matthiola incana) exposed to normal temperature and normal light intensity (18 °C/11 °C, 500 μmol·m-2·s-1, NN), low temperature and normal light intensity (4 °C/1 °C, 500 μmol·m-2·s-1, LN), normal temperature and low light intensity (18 °C/11°C, 100 μmol·m-2·s-1, NL), and low temperature and low light intensity (4 °C/1 °C, 100 μmol·m-2·s-1, LL). The results showed that the plant height, stem diameter, leaf area, shoot fresh/dry weight, and underground fresh/dry weight of violet inoculated with PGPR were 40%, 17%, 13%, 25%, 41%, 30%, and 38% higher than the control, respectively. In addition, the total root length, mean root diameter, number of root tips, number of bifurcated root tips, and root vigor were 24%, 23%, 14%, 30%, and 21% higher in the inoculated group than in the control group, respectively. PGPR promoted chlorophyll accumulation in plants, and the net photosynthetic rate of violets was 32% higher in plants inoculated with PGPR than in control plants. PGPR also significantly promoted the maximum photochemical conversion efficiency of photosystem II (PSII) and the potential activity of PSII under UV light. After inoculation with PGPR, the content of MDA decreased by 16.8%, and the activities of superoxide dismutase and peroxidase increased by 19.2% and 20.0%, respectively. Therefore, PGPR can promote the growth of violet plants by increasing the photosynthetic capacity, activating the antioxidant enzyme system, and reducing damage induced by exposure to low light intensity.

Complete mitochondrial genome assembly of Juglans regia unveiled its molecular characteristics, genome evolution, and phylogenetic implications

BackgroundThe Persian walnut (Juglans regia), an economically vital species within the Juglandaceae family, has seen its mitochondrial genome sequenced and assembled in the current study using advanced Illumina and Nanopore sequencing technology.ResultsThe 1,007,576 bp mitogenome of J. regia consisted of three circular chromosomes with a 44.52% GC content encoding 39 PCGs, 47 tRNA, and five rRNA genes. Extensive repetitive sequences, including 320 SSRs, 512 interspersed, and 83 tandem repeats, were identified, contributing to genomic complexity. The protein-coding sequences (PCGs) favored A/T-ending codons, and the codon usage bias was primarily shaped by selective pressure. Intracellular gene transfer occurred among the mitogenome, chloroplast, and nuclear genomes. Comparative genomic analysis unveiled abundant structure and sequence variation among J. regia and related species. The results of selective pressure analysis indicated that most PCGs underwent purifying selection, whereas the atp4 and ccmB genes had experienced positive selection between many species pairs. In addition, the phylogenetic examination, grounded in mitochondrial genome data, precisely delineated the evolutionary and taxonomic relationships of J. regia and its relatives. We identified a total of 539 RNA editing sites, among which 288 were corroborated by transcriptome sequencing data. Furthermore, expression profiling under temperature stress highlighted the complex regulation pattern of 28 differently expressed PCGs, wherein NADH dehydrogenase and ATP synthase genes might be critical in the mitochondria response to cold stress.ConclusionsOur results provided valuable molecular resources for understanding the genetic characteristics of J. regia and offered novel perspectives for population genetics and evolutionary studies in Juglans and related woody species.

Genome-wide identification and comprehensive analysis of the AP2/ERF gene family in Prunus sibirica under low-temperature stress

BackgroundAP2/ERF transcription factors are involved in the regulation of growth, development, and stress response in plants. Although the gene family has been characterized in various species, such as Oryza sativa, Arabidopsis thaliana, and Populus trichocarpa, studies on the Prunus sibirica AP2/ERF (PsAP2/ERF) gene family are lacking. In this study, PsAP2/ERFs in P. sibirica were characterized by genomic and transcriptomic analyses.ResultsIn the study, 112 PsAP2/ERFs were identified and categorized into 16 subfamilies. Within each subfamily, PsAP2/ERFs exhibited similar exon-intron structures and motif compositions. Additionally, 50 pairs of segmentally duplicated genes were identified within the PsAP2/ERF gene family. Our experimental results showed that 20 PsAP2/ERFs are highly expressed in leaves, roots, and pistils under low-temperature stress conditions. Among them, the expression of PsAP2/ERF21, PsAP2/ERF56 and PsAP2/ERF88 was significantly up-regulated during the treatment period, and it was hypothesised that members of the PsAP2/ERF family play an important role inlow temperature stress tolerance.ConclusionsThis study improves our understanding of the molecular basis of development and low-temperature stress response in P. sibirica and provides a solid scientific foundation for further functional assays and evolutionary analyses of PsAP2/ERFs.

Recent Insights into the Physio-Biochemical and Molecular Mechanisms of Low Temperature Stress in Tomato.

Climate change has emerged as a crucial global issue that significantly threatens the survival of plants. In particular, low temperature (LT) is one of the critical environmental factors that influence plant morphological, physiological, and biochemical changes during both the vegetative and reproductive growth stages. LT, including abrupt drops in temperature, as well as winter conditions, can cause detrimental effects on the growth and development of tomato plants, ranging from sowing, transplanting, truss appearance, flowering, fertilization, flowering, fruit ripening, and yields. Therefore, it is imperative to understand the comprehensive mechanisms underlying the adaptation and acclimation of tomato plants to LT, from the morphological changes to the molecular levels. In this review, we discuss the previous and current knowledge of morphological, physiological, and biochemical changes, which contain vegetative and reproductive parameters involving the leaf length (LL), plant height (PH) stem diameter (SD), fruit set (FS), fruit ripening (FS), and fruit yield (FY), as well as photosynthetic parameters, cell membrane stability, osmolytes, and ROS homeostasis via antioxidants scavenging systems during LT stress in tomato plants. Moreover, we highlight recent advances in the understanding of molecular mechanisms, including LT perception, signaling transduction, gene regulation, and fruit ripening and epigenetic regulation. The comprehensive understanding of LT response provides a solid basis to develop the LT-resistant varieties for sustainable tomato production under the ever-changing temperature fluctuations.

Enhanced Stability Under Positive Bias Temperature Stress in Oxide Thin Film Transistors with Double Gate Structure By Improving Bottom Channel Interface

In this paper, we discuss the causes of reliability degradation in oxide TFTs with a double gate structure and propose methods for improvement. Reducing IGZO deposition power significantly improves PBTS (Positive Bias Temperature Stability) reliability in double gate structures. This improvement is attributed to reduction of excess oxygen defects accumulated at the bottom channel interface, as inferred from the difference in PBTS results for the top single gate and double gate structures

Quantitative Dynamic Evolution of Unoccupied States in Hydrogen Diffused InGaZnSnO TFT under Positive Bias Temperature Stress

Quantitative Dynamic Evolution of Unoccupied States in Hydrogen Diffused InGaZnSnO TFT under Positive Bias Temperature Stress

Fabrication and characterization of mayonnaise based on xanthan gum/lysozyme nanoparticles and konjac glucomannan as egg yolk substitutes under different temperature stresses

High cholesterol levels in mayonnaise pose a potential health threat to consumers, and there is an urgent need to develop cholesterol-reduced mayonnaise to meet consumer demand. Therefore, the aim of this study was to prepare a cholesterol-reduced Pickering emulsion mayonnaise (PEM) by replacing egg yolk with xanthan gum/lysozyme nanoparticles (XG/Ly NPs) and konjac glucomannan (KGM). In addition, the decorated appearance, droplet size, centrifugal stability, microstructure, and rheological properties of PEM were determined at different temperature fields (ambient, pasteurized, and refrigerated). The results showed that KGM provided additional network structure for PEM when the yolk substitution rate was no more than 40%, limiting oil droplet aggregation, as evidenced by the enhanced centrifugal stability and significantly reduced droplet size (P < 0.05). Moreover, the PEM supplemented with 0.2% KGM at 40% yolk substitution showed good viscoelasticity and small particle size (12.4 ± 0.7 μm) after pasteurization (65 °C for 30 min) and 30 days of refrigeration. Overall, XG/Ly NPs and KGM can be used as potential egg yolk substitutes and provide a new theoretical reference for the food industry to develop highly stable cholesterol-reduced mayonnaise.

Monitoring the thermal state of an ingot with beveled and rounded corners in a slab crystallizer of a CCM

The organization of ingot cooling in the continuous caster mold affects the reliability, productivity and quality of the resulting ingots. Insufficient heat exchange between the solidifying metal and the wall of the mold leads to a decrease in the thickness of the solid shell of the ingot, which causes the formation of surface defects, and when the ingot is pulled out of the mold, emergency breakthroughs occur. Excessive heat transfer leads to an increase in the thickness of the solid shell, which entails excessive shrinkage of the ingot surface with the formation of a gap between the solid shell of the ingot and the walls of the mold. The appearance of an air gap leads to increased wear of the copper walls of the mold. There is a design of copper walls that makes it possible to reduce the normal component of forces that occurs during wear, reduce the temperature gradient and stress concentration in the corner of the ingot, and also bring the thickness of the hard crust stocking in the corner closer to the perimeter of the mold. However, the thermal state of the formed ingot with such a crystallizer design remains poorly understood. The goal of the work is to create a virtual tool for monitoring the operation of the mold of a slab continuous caster based on the development of a mathematical and computer model of the thermal state of an ingot with beveled and rounded corners. The temperature distribution in the ingot was calculated using the quasi-equilibrium theory of solidification. The numerical implementation of the mathematical model and obtaining an approximate solution using a computer were carried out using the finite dif-ference method and an implicit difference scheme. A computer program was developed in the Matlab development environment. Using computer modeling, the temperature distribution over the volume of the slab at the outlet of the mold with beveled and rounded corners was obtained. The program for the selected mold design allows you to analyze the solidification of the ingot skin and monitor this process for the selected steel grade and specified casting technological parameters

Nano aluminum nitride fillers for enhanced mechanical and thermal properties of GFRP in cryogenic temperature settings

Glass fiber-reinforced polymer (GFRP) composites, with epoxy resin or a blend of cyanate and epoxy resins as the matrix, have been used as insulating materials of high-field, large-scale superconducting magnets for accelerators and magnetic confinement fusion. However, the GFRP does not fully meet the requirements for the next generation of magnetic confinement fusion with respect to the mechanical and thermal performance at cryogenic temperature and huge electromagnetic stress. This paper introduces a method for enhancing both the mechanical and thermal properties of the GFRP composites using aluminum nitride (AlN) nanoparticles. The fabrication of the AlN-GFRP composite involved a method that combines “dip absorption” with vacuum-assisted resin transfer molding (VARTM). The dip absorption method was utilized to deposit AlN nanopowders onto glass fibers, resulting in the preparation of AlN-glass fiber layers. Subsequently, the AlN-woven glass fibers were incorporated to reinforce the cyanate ester/epoxy based composites using the VARTM technology. The mechanical and thermal properties of the AlN-GFRP composites were assessed across varying temperatures. The results indicate that the short-beam shear strength (SBS strength) of the AlN-GFRP composites improves at cryogenic temperatures compared to that of the GFRP composites without AlN. Additionally, enhanced thermal conductivities are observed across different temperature ranges for the AlN-GFRP composites. The coefficient of thermal expansion between 77 K and 300 K of the composites significantly decreases with the addition of the AlN nanopowders.

Analysis of Genetic Variability, Heritability, and Genetic Advance for Yield-Associated Traits under High Temperature Stress in Tomato (Solanum lycopersicum L.)

The objective of this study was to examine the genetic variability, heritability, and genetic advancement in tomato plants (both parents and hybrids) in terms of their tolerance to high temperatures. The research was conducted at the ICAR-Indian Institute of Vegetable Research (ICAR-IIVR) in Varanasi during the summer season of 2024 (February-May). In this study, a total of 23 tomato genotypes comprising 8 parent varieties and 15 hybrid crosses were cultivated using a completely randomized block design (CRBD). The ANOVA analysis indicated a notable level of genetic variability present in the genotypes for the traits under investigation. Both the phenotypic and genotypic coefficient of variation showed a higher PCV for all traits examined in relation to their respective GCV, highlighting the significant impact of environmental factors on the results. Significant heritability and genetic advance were noted for various traits, including average fruit weight, fruit quantity per plant, fruit setting, plant yield, anther tip burning, plant height, seed count per fruit, stigma exertion, crop duration, and pollen viability, underscoring their potential for genetic improvement in future research endeavors. Our research findings indicate that these characters are influenced by the cumulative effects of genes, highlighting the potential effectiveness of employing a selection method to enhance their tolerance to high temperatures in tomato plants.

Identification and mapping of QTLs and their corresponding candidate genes controlling high night-time temperature stress tolerance in wheat (Triticum aestivum L.).

With every 1°C rise in temperature, yields are predicted to decrease by 5%-6% for both cool and warm season crops, threatening food production, which should double by 2050 to meet the global demand. While high night-time temperature (HNT) stress is expected to increase due to climate change, limited information is available on the genetic control of the trait, especially in wheat (Triticum aestivum L.). To identify genes controlling the HNT trait, we evaluated a doubled haploid (DH) population developed from a cross between an HNT tolerant line KSG1203 and KSG0057, a selection out of a mega variety PBW343 from South East Asia that turned out to be HNT susceptible. The population, along with the parents, were evaluated under 30°C night-time (HNT stress) keeping the daytime temperature to normal 22°C. The same daytime and 16°C night-time temperature were used as a control. The HNT treatment negatively impacted all agronomic traits under evaluation, with a percentage reduction of 0.5%-35% for the tolerant parent, 8%-75% for the susceptible parent, and 8%-50% for the DH population. Performed using sequencing-based genotyping, quantitative trait locus (QTL) mapping identified 19 QTLs on 13 wheat chromosomes explaining 9.72%-28.81% of cumulative phenotypic variance for HNT stress tolerance, along with 13 that were for traits under normal growing conditions. The size of QTL intervals ranged between 0.021 and 97.48 Mb, with the number of genes ranging between 2 and 867. A candidate gene analysis for the smallest six QTL intervals identified eight putative candidates for night-time heat stress tolerance.

Study on the influence mechanism of electromagnetic field on multifield coupling during the laser cladding Fe60 process

During laser cladding, microdefects such as pores, cracks, and segregation inevitably occur. Practical experience has shown that applying an electromagnetic field is an effective method for eliminating these microdefects during the cladding process. In the study, a multifield coupling three-dimensional numerical model was established for the electromagnetic field-assisted laser cladding Fe60 process. The instantaneous evolution law in the temperature field, flow field, and stress field under the influence of a magnetic field and without magnetic influence was calculated and revealed. At the same time, the two were compared and analyzed, focusing on the influence of an external electromagnetic field on the flow of molten pool Marangoni and its action mechanism. The results show that under the electromagnetic conditions applied in the study, the maximum magnetic induction intensity and the maximum Lorentz force density in the molten pool reach 0.13 T and 6.84 × 103 N/m3. Under the influence of magnetic force, the “double vortex” flow of Marangoni convection is asymmetrically distributed in the center of the molten pool. The fluid flow line has irregular flow and the circulation area generated at the front of the molten pool is larger in the corresponding scanning direction. Under the magnetic field influence, the overall flow velocity of the molten pool obviously increases, and the maximum flow velocity of the molten pool reaches 0.28 m/s. The study lays a significant theoretical foundation for revealing the mechanism of laser cladding assisted by a magnetic field.

Transcriptomic and metabolomic investigations of methyl jasmonate-mediated enhancement of low temperature stress resistance in Cassia obtusifolia L.

Low temperature stress negatively impacts plant growth and development, reducing crop yields by disrupting metabolite production and accumulation. Cassia obtusifolia L., a widely cultivated medicinal plant in subtropical regions, is particularly vulnerable to such stress. Methyl jasmonate (MeJA) regulates plant growth, defense mechanisms, and secondary metabolite production. This study investigated how C. obtusifolia responds to low temperature stress under MeJA treatment using transcriptomic and metabolomic approaches. MeJA treatment upregulated several transcription factor families, including APE/ERF-ERF, WRKY, NAC, and MYB-related, which modulated the plant's response to cold stress. These transcription factors influenced the expression of genes involved in glycolysis, sugar metabolism, and amino acid pathways, contributing to the plant's adaptive responses. Differentially expressed genes were associated with key metabolic processes such as flavonoid biosynthesis, ribosome function, glycolysis/gluconeogenesis, and sugar metabolism. Using H-NMR and LC-MS techniques, we observed that MeJA induced the accumulation of sugars and amino acids in the leaves of C. obtusifolia seedlings under cold stress, while levels of three flavonoid compounds Isoliquiritigenin, Kaempferol-7-O-glucoside, and Phloretin significantly decreased. Enrichment analysis indicated that MeJA modulates the biosynthetic pathways of these compounds in a dose-dependent manner. Integrating metabolomic and transcriptomic data further elucidated alterations in the flavonoid biosynthetic network and other metabolic pathways under low temperature stress. These findings offer insights into the molecular mechanisms underlying flavonoid synthesis and other metabolic adjustments in C. obtusifolia under MeJA treatment.

Hydrogenolysis of guaiacol and lignin to phenols over Ni/Nb2O5[sbnd]HZSM-5 catalyst

Selective hydrogenolysis of CAr-O bonds in lignin to produce aromatic compounds typically necessitates severe conditions. We developed a Ni/Nb2O5HZSM-5 catalyst that facilitates direct cleavage of guaiacol's aryl ether bonds at reduced temperatures (200 °C) and pressure (0.1 MPa H2), achieving a conversion of 89.5 % with the selectivity of phenol at 81.7 %, while retaining its activity after five cycles. The Ni/Nb2O5HZSM-5 exhibits a higher yield of phenol (49.1 mmolphenol·gNi−1·h−1), currently achieving the highest phenol yield among Ni-based catalysts. The addition of Nb2O5 enhances the dispersion of Ni and augments the effective surface area. In addition, the strong interaction of Nb with the HZSM-5 changed the electronic state of Nb and enhanced the resistance of the catalyst to high temperature and mechanical stress. Employing this catalyst for lignin depolymerization in an aqueous medium led to a 17.0 wt% yield of alkyl phenolic compounds. This approach represents an advancement in biomass resource conversion, circumventing the dependency on high-pressure and precious-metal catalysts, and signaling a new trajectory for sustainable biomass utilization in scientific research.

Short duration heatwaves increase body temperature and alter blood gas balance but may not cause oxidative stress and intestinal structure variations in lambs

This study investigated the impact of short duration heatwaves (HW) on the body temperature, blood gas, intestinal histology, and oxidative stress parameters of second cross lambs. Seventy-two second cross lambs [Poll Dorset × (Border Leicester × Merino)] were selected and exposed to either one, three or five days HW (28–38°C and 40–60 % relative humidity (RH)) or thermoneutral (TN; 18–21°C, 40–55 % RH) conditions in climate-controlled chambers. Lambs exposed to one to five days HW exhibited higher face, eye and ear temperature compared to animals exposed to equal duration under TN conditions. HW also had a significant impact on blood gas parameters which include higher blood pH, and lower CO2, Ca2+, Na+, CHCO3- and Cl-. However, HW lambs’ histology structure of the ileum and the GSSG: GSH of the ileum and Longissimus thoracis (LT) muscle were not influenced (P > 0.05) by HW. LT muscle showed higher total antioxidant capacity (TAC) in HW conditions, but the TAC of intestine and blood had no difference between HW and TN groups. These results suggest that short-duration HW (one to five days) had a significant impact on lambs’ body temperature and blood parameters, but neither caused oxidative stress nor any changes in their intestinal structure.

Effect of fertility levels and stress mitigating chemicals on nutrient content, uptake, intercropping advantage and competition effect in cowpea-baby corn intercropping

The primary goal of this study was to analyze how various row ratios of intercrops, in conjunction with different fertilizer levels with spray of two stress mitigating chemical, affect nutrient content, land productivity, and economic viability during Summer season. Furthermore, we aimed to explore the competitive dynamics within legume/cereal intercropping systems. Hence, A field experiment at Agriculture University, Kota, during the summers of 2019 and 2020, investigated different cowpea + baby corn intercropping system's intercropping indices, nutrient dynamics, uptake, and post-harvest soil nutrient balance under varying recommended fertilizer levels and foliar spray of stress mitigating chemicals. Using a split-split plot design replicated four times, the experiment involved thirty treatment combinations, including five intercropping techniques viz. Sole cowpea, sole baby corn, cowpea + baby corn 2:1, cowpea + baby corn 3:1, cowpea + baby corn 4:1 in the main plot, three fertility levels viz. 100 %, 125 % and 150 % recommended dose of fertilizer (RDF) in subplots, and two stress mitigation chemicals; CaCl2 0.5 % and KNO3 1% in sub-subplots. The findings revealed notable trends, including nitrogen (N) and (P) content in cowpea seeds and straw, baby corn cobs and fodder, as well as enhanced land-equivalent ratio (LER) and monetary advantage index (MAI) within the cowpea + baby corn 2:1 row ratio. However, despite these advantages, total N and P uptake were markedly higher in sole crops. Notably, sole cowpea demonstrated the highest actual N and P balance and lowest was under sole baby corn. Among the fertility levels, the 150 % RDF level exhibited the most favorable outcomes across various parameters, including LER, MAI, NP content, and uptake in both crops. Additionally, higher fertility levels correlated with increased apparent and actual soil nutrient balances. While, among stress mitigation chemicals, CaCl2 0.5 % resulted in significantly heightened N and P uptake. Hence, to optimize intercropping dynamics and maintain soil nutrient balance, it is advisable to intensify cowpea cultivation along with baby corn in a 2:1 row ratio, utilizing 150 % RDF is beneficial. Additionally, alleviating higher temperature stress during the summer season can be achieved by applying a 0.5 % solution CaCl2 through spraying at the flowering and pod development stages of cowpea.

Unsteady Two-Dimensional Drift of a Viscoelastic Fluid with Magnetic and Thermal Effects: A Perturbation Approach

This study explores the unsteady, two-dimensional flow of an electrically conductive, viscoelastic, and incompressible fluid past a uniformly moving, infinite, non-conducting vertical plate, in the presence of a uniform first-order chemical process involving mass and heat transfer. A uniform magnetic field is applied perpendicular to the flow, with the magnetic Reynolds number assumed small to neglect the induced magnetic field. The governing equations are solved using a regular perturbation method, yielding approximate solutions for concentration, velocity, temperature, and shear stress at the plate. Additionally, mass and heat transfer rates are determined, with the influence of viscoelasticity and other physical parameters emphasized. Where applicable, results are graphically represented.

Optimization and Analysis of Refill Friction Stir Spot Welding (RFSSW) Parameters of Dissimilar Aluminum Alloy Joints by FE and ANN Methods.

The quality of the refill friction stir spot welding (RFSSW) process is heavily dependent on the selected welding parameters that influence the resultant joint characteristics. Thermomechanical phenomena integral to the process were investigated using finite element (FE) analysis on two dissimilar materials. This FE analysis was subsequently validated through controlled experiments to ensure reliability. An artificial neural network (ANN) was employed to create a neural model based on an experimental setup involving 120 different sets of welding parameters. The parameters adjusted in the experimental plan included pin penetration depth, rotational speed, retention time, and positioning relative to material hardness. To assess the neural model's accuracy, outputs such as maximum temperature and normal stress at the end of the welding process were analyzed and validated by six data sets selected for their uniform distribution across the training domain.

Short-Term Warming Induces Cyanobacterial Blooms and Antibiotic Resistance in Freshwater Lake, as Revealed by Metagenomics Analysis

Climate change threatens freshwater ecosystems, potentially intensifying cyanobacterial blooms and antibiotic resistance. We investigated these risks in Cosseys Reservoir, New Zealand, using short-term warming simulations (22 °C, 24 °C, and 27 °C) with additional oxidative stress treatments. A metagenomic analysis revealed significant community shifts under warming. The cyanobacterial abundance increased from 6.11% to 20.53% at 24 °C, with Microcystaceae and Nostocaceae proliferating considerably. The microcystin synthesis gene (mcy) cluster showed a strong association with cyanobacterial abundance. Cyanobacteria exhibited enhanced nutrient acquisition (pstS gene) and an upregulated nitrogen metabolism under warming. Concurrently, antibiotic resistance genes (ARGs) increased, particularly multidrug resistance genes (50.82% of total ARGs). A co-association network analysis identified the key antibiotic-resistant bacteria (e.g., Streptococcus pneumoniae and Acinetobacter baylyi) and ARGs (e.g., acrB, MexK, rpoB2, and bacA) central to resistance dissemination under warming conditions. Oxidative stress exacerbated both cyanobacterial growth and ARGs’ proliferation, especially efflux pump genes (e.g., acrB, adeJ, ceoB, emrB, MexK, and muxB). This study demonstrated that even modest warming (2–5 °C) could promote both toxic cyanobacteria and antibiotic resistance. These findings underscore the synergistic effects of temperature and oxidative stress posed by climate change on water quality and public health, emphasizing the need for targeted management strategies in freshwater ecosystems. Future research should focus on long-term impacts and potential mitigation measures.