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Half-moon events are a special type of microseismic source mechanism that is found at various hydraulic-fracturing sites, but hardly observed in natural seismicity. This event type can be explained either by a vertical slip on a nearly vertical fault plane or by a horizontal slip on a nearly horizontal fault plane. For this, special stress conditions are required, for instance, nearly equal horizontal and vertical compressional stresses and significant shear stresses. Such conditions are created during hydraulic stimulation as shown by our numerical simulations. By applying fracture pressure to the surface of the hydraulic fracture, the stress field in the vicinity of the hydraulic fracture can locally rotate and horizontal or vertical faults become optimally oriented. We found that such rotations can occur in locations where the elastic properties of rocks change (i.e., the fracture crosses a layer interface) or at the tips of the hydraulic fracture. Depending on the stress regime, our model explains half-moon events generated by slip on nearly horizontal fault planes in strike-slip environments and by slip on nearly vertical fault planes in normal faulting tectonics. Moreover, our models explain several common characteristics observed in multiple case studies. This includes the observation of the high portion of half-moon events and opposed shear senses in different depths and on opposite sides of the fracture.

Essential macro- and microelements availability strictly influences photosynthetic process as well as the overall plant status. Besides essential macro- and micronutrients, a group of other elements described as 'beneficial' has been proposed to ameliorate plant performances under optimal and/or stressful conditions. The first explanation of the term 'essential', as suggested by Arnon and Stout in 1939, defined beneficial elements as not essentials since they are not necessary for plants to complete their life cycle. However, at low amounts, they can exert promoting effects on plant performances, including photosynthesis. In this review, we summarize the positive effect of seven beneficial elements (Se, Si, Na, I, Ti, Ce, and La) on plant photosynthetic processes to depict a clear picture of the influences of these beneficial elements on photosynthesis.

This study numerically investigates the influence of foundation conditions, in combination with other factors such as wall height and reinforcement and facing stiffness, on the behaviour of reinforced soil walls (RSWs) under working stress conditions. The foundation was simulated using different stiffnesses and geometries (with and without slope). The results highlight the importance of the combined effect of foundation conditions and the abovementioned factors on the performance of RSWs. The results of these analyses indicate that the shape of the distribution of the maximum reinforcement loads (Tmax) with respect to wall height depends on the combined effect of the foundation condition, facing and reinforcement stiffness, and wall height, and varies from trapezoidal to triangular. Additionally, the results indicate that the effect of variations in foundation stiffness on reinforcement tension mobilisation decreases with wall height. Furthermore, the Tmax prediction accuracy of three design methods were evaluated and some limitations of each method are presented and discussed.

No high-performance thin-layer chromatography (HPTLC) techniques have been established for the determination of tedizolid phosphate (TDZP) in pharmaceutical products or physiological fluids. Therefore, a rapid and highly sensitive stability-indicating HPTLC technique has been developed for the determination of TDZP in commercial formulations with a classical univariate calibration. The HPTLC‒densitometry analysis of TDZP was carried out via chloroform‒methanol (90:10, V/V) mobile phase. The determination of TDZP was performed at the wavelength of 300 nm. The proposed HPTLC technique was linear in the range of 10‒2000 ng band‒1. In addition, the method was found to be highly accurate (% recovery = 98.53‒101.74%), precise (%CV = 0.67‒0.91%), robust (%CV = 0.83‒0.86%), highly sensitive (LOD = 3.41 ng band‒1, LOQ = 10.23 ng band‒1) for the determination of TDZP. The proposed technique was also able to detect TDZP in the presence of its degradation products under various stress conditions and it can be considered as a stability-indicating method. The proposed HPTLC technique was applied for the analysis of TDZP in its commercial formulations. The TDZP contents of commercial tablets and injection were determined as 98.41% and 101.23%, respectively. These results suggested that the proposed HPTLC technique can be applied for the routine analysis of TDZP in its commercial products and newly established formulations.

The rock indentation tests by a conical pick were conducted to investigate the rock cuttability correlated to confining stress conditions and rock strength. Based on the test results, the regression analyses, support vector machine (SVM) and generalized regression neural network (GRNN) were used to find the relationship among rock cuttability, uniaxial confining stress applied to rock, uniaxial compressive strength (UCS) and tensile strength of rock material. It was found that the regression and SVM-based models can accurately reflect the variation law of rock cuttability, which presented decreases followed by increases with the increase in uniaxial confining stress and the negative correlation to UCS and tensile strength of rock material. Based on prediction models for revealing the optimal stress condition and determining the cutting parameters, the axial boom roadheader with many conical picks mounted was satisfactorily utilized to perform rock cutting in hard phosphate rock around pillar.

The salivary glands are closely associated with stress conditions and the neuroendocrine system. The concentrations of these salivary biomarkers fluctuate with a person’s disease status. Until now, salivary diagnostics have been promising; however, the analytical tools for detecting salivary biomarkers have remained burdensome due to the lack of user-friendly and cost-effective equipment. In this study, we used a microfluidic starch-coated paper-based chip to isolate ɑ-amylase from human saliva. The concentration of ɑ-amylase on the head and tail sections of the paper-based chip was compared in the presence or absence of starch. We found that ɑ-amylase was highly concentrated only in the head section of the starch-coated paper-based chip through Western blotting (WB) and enzyme-linked immunosorbent assay (ELISA). We expect our designed paper-based chip will aid in α-amylase detection technologies using saliva and small amounts of other biofluids including blood, tears, pancreatic juice, and urine.

Wood vinegar is widely used as a strong antioxidant, bacteria prevention, plant growth agent, an insecticide, and its effectiveness is shown in heavy metal treatment at this time.Wood vinegar liquid contains organic acids and phenols, which are effective in adsorbing heavy metals. Although a lot of studies have been conducted on the adsorption of heavy metals from biochar, the effect of mixing biochar and wood vinegar liquid on plant budding, and soil heavy metal morphology changes few studies have been analyzed. This paper analyzes the effects of Wood vinegar and biochar on the sprouting of pakchoi grown in different threats of cadmium from the nature of Wood vinegar. As a result, it was confirmed that the optimum concentration of the applied fertilizer wood vinegar that lowers the plant effectiveness of Cadmium was 1.0%. The fresh weight of pakchoi changed significantly in the order of biochar + wood vinegar 1.0% mixing> biochar> control. When 5.0% Biochar was mixed with 1.0% wood vinegar, the immobilization effect of the residual state and the carbonate bound cadmium in the soil was the highest. The combined application of wood vinegar and biochar promotes the germination of pakchoi, and has a significant inactivation effect on cadmium-contaminated soil; the results of analyzing the effectiveness of the mixing of wood vinegar and biochar and separate fertilization for each soil index show that, Compared to before sowing the pH ratio of the mixed treatment of biochar + wood vinegar is higher than that of the single treatment zone, which is as high as between 6.6-6.8, the EC is reduced to 2-59mS/cm width, and the CEC is increased by 0.27-2.21 times. It shows that under heavy metal stress, the mixed treatment of biochar+wood vinegar solution 1.0% is more effective than the treatment of biochar alone and the control.

As plants are living forms that cannot communicate their condition (stress, requirements) as animals, they have been studied to find chemical or physical signals that could help understand the plant requirements for several purposes such as substances and food production. Different research supports electrical signals (ES) related to different stress conditions in plants as damage or drought. Some others have identified and classified these signals generated by stress condition using diverse Artificial intelligence (AI) techniques. Finally, some other researches have used electricity as a stimulator obtaining a response as chemical compounds production, gene expression and growth-promoting. In a few words, ES from plants can be interpreted, which could also be sent back to plants. Based on the bibliographic revision in this work, it is proposed that experiments and research, where the ES serves to activate chemical and physiological mechanisms or as elicitor, are required to consider the electrical signals as a possible communication pathway with plants.

The qualitative and quantitative chemical compositions of Astragalus vulpinus Willd. herb were investigated and included saponins, flavonoids, and ascorbic acid. Porsolt tests on white outbred male rats subjected to informational stress were used to study the psychomodulating effect of A. vulpinus herbal extract on their behavior. It was established that extract of A. vulpinus herb produced protective action under informational stress conditions by restoring changes of the psychoemotional status.

The content and composition of neutral lipids (NL), glycolipids (GL), phospholipids (PhL), and fatty acids (FA) from Chenopodium album seeds are established for the first time. NL contained 15 identified FA; PhL, 16; and GL, 19 constituents including trans-18:1n9. The stress-protective effects of NL, FA, methyl esters of FA, and unsaponifiable substances (US) on the growth and development of wheat and cotton sprouts were studied under salt stress conditions. NL at a concentration of 0.001% and US and FA at a concentration of 0.01% had the greatest effects on the growth of wheat roots. US at a concentration of 0.001% stimulated growth of roots and stems of cotton sprouts; FA, only growth of roots at a concentration of 0.0001%.

Seed germination is one of the key processes in nature, with several studies focused on improving this process. One successful strategy is to expose seeds to hydrogen sulfide (H2S), a cytotoxic rea...

This study was carried out to evaluate Cu uptake, mobility, and accumulation in Cyperus rotundus and define the physiological strategy it employs under copper stress conditions. The experiment was ...

Doped-multilayer-graphene (DMLG) interconnects employing the subtractive-etching (SE) process have opened a new pathway for designing interconnects at advanced technology nodes, where conventional metal wires suffer from significant resistance increase, self-heating (SH), electromigration (EM), and various integration challenges. Even though single-level scaled graphene wires have been shown to possess better performance and reliability with respect to dual-damascene (DD) and SE-enabled metal wires, a multi-level graphene interconnect technology (with vias) has remained elusive, which is of paramount importance for its integration in future technology nodes. This work, for the first time, addresses that need by engineering a CMOS-compatible solid-phase growth technique to yield large-area multilayer graphene (MLG) on dielectric (SiO2) and metal (Cu) substrates and subsequently demonstrating multi-level MLG interconnects with metal vias. Using rigorous theoretical and experimental analyses, we demonstrate that multi-level MLG interconnects with metal vias undergo < 2% change in the via resistance under accelerated stress conditions, demonstrating its superior reliability against SH and EM, making them ideal candidates for sub-10 nm nodes.

The effect of marine calcite, a mixture of ortho- and polysilicic acid as well as orthosilicic acid applied as a foliar spray on the chemical composition of sugar beet leaves in the critical phase of nutrient supply (beginning of July) but also leaves and roots during harvest time in 2015–2016, was studied. The content of silicon in the leaves ranged from 1.24 to 2.36 g kg−1 d.m. at the beginning of July, 3.85–5.34 g kg−1 d.m. during harvest and 2.91–4.20 g kg−1 d.m. in the roots. The foliar application of silicon caused a significant increase in the content of magnesium and calcium in leaves (in July) as compared to the control. The sugar beet consumes approx. 75 kg Si ha−1, which is almost 3.5 times more than P and 20% more than Mg thus proving its importance for its species. About 70% of the silicon taken up by sugar beet is stored in roots and 30% in leaves. The pure sugar yield is most favorably influenced by two- and threefold foliar application of the product containing silicon in the form of orthosilicic acid stabilized with choline, and a threefold mixture of ortho- and polysilicic acid. The increase in the pure sugar yield is not the result of a change in the chemical composition of sugar beet plants, but their more efficient functioning after foliar application of silicon under stress conditions caused by water shortage.

The unique environment of space is characterized by several stress factors, including intense radiation, microgravity, high vacuum and extreme temperatures, among others. These stress conditions individually or in-combination influence genetics and gene regulation and bring potential evolutionary changes in organisms that would not occur under the Earth's gravity regime (1 × g). Thus, space can be explored to support the emergence of new varieties of microbes and plants, that when selected for, can exhibit increased growth and yield, improved resistance to pathogens, enhanced tolerance to drought, low nutrient and disease, produce new metabolites and others. These properties may be more difficult to achieve using other approaches under 1 × g. This review provides an overview of the space microgravity and ionizing radiation conditions that significantly influence organisms. Changes in the genomics, physiology, phenotype, growth and metabolites of organisms in real and simulated microgravity and radiation conditions are illustrated. Results of space biological experiments show that the space environment has significant scientific, technological and commercial potential. Combined these potentials can help address the future of life on Earth, part of goal e of astrobiology.

All human cells use O-GlcNAc protein modifications (O-linked N-acetylglucosamine) to rapidly adapt to changing nutrient and stress conditions through signaling, epigenetic, and proteostasis mechanisms. A key challenge for biologists in defining precise roles for specific O-GlcNAc sites is synthetic access to homogenous isoforms of O-GlcNAc proteins, a result of the non-genetically templated, transient, and heterogeneous nature of O-GlcNAc modifications. Toward a solution, this review details the state of the art of two strategies for O-GlcNAc protein modification: advances in "bottom-up" O-GlcNAc peptide synthesis and direct "top-down" installation of O-GlcNAc on full proteins. We also describe key applications of synthetic O-GlcNAc peptide and protein tools as therapeutics, biophysical structure-function studies, biomarkers, and as disease mechanistic probes to advance translational O-GlcNAc biology.

We investigated if high irradiance imposes stress conditions and differently affects the performance of species from the early-successional light-demanding group and if the costs associated with plasticity underlie the trade-off between growth and survival. Survival, growth, chlorophyll a fluorescence, and carbon stable isotopic ratio (δ13C) were measured in seedlings of four tree species in a restoration area in the Atlantic Forest under full-sun exposure and partial shading treatments. The maximal quantum yield of PSII indicated stress conditions mainly in the full-sun exposure treatment (values from 0.72 to 0.81). The δ13C ranged from -31.9 to -30.4‰, but did not differ between treatments for three species, suggesting that C assimilation in initial restoration conditions is stressful even in shade. The survival scaled negatively with growth and plasticity adjustments. We conclude that early-successional species do not form a homogenous species group because they differ in functional responses to stress, and phenotypic plasticity, with these variations showing a strong link with the trade-off between growth and survival. This information should be taken into account for species selection in restoration programs.

Industrial hemp (Cannabis sativa L.) is a fibrous plant with high biomass production, and can survive under heavy metal stress conditions. To determine the growth potential of industrial hemp on le...

Cuticular waxes are the covering of the outer layer of the plant, consist of hydrocarbon appears like whitish film or bloom in plant organs. They play a vital role like a safeguard from different stress condition in the plant. Since environmental factors are active regulators of cuticular wax biosynthesis, composition, quantity, and deposition, it is evident that cuticular wax is associated with plant stress responses. The diversity of cuticular wax compositions is a proof of the wealth of genes associated in plant wax production. Moreover, a number of wax genes were distinguished in plant/crops at abiotic stress conditions but, regulation of control of those wax genes has not been studied very well in major crop plants at abiotic conditions. A very few transcriptions factors were identified to regulate the expression level of wax genes of cuticular wax biosynthesis at abiotic stress condition. However, further study is needed to identify more candidate transcriptional regulation factors to cuticular wax production in different crop plants in diverse abiotic environments. Therefore, regulation of cuticular wax production under diverse abiotic stresses and the role of transcription factors into the plant cuticular wax accumulation will be helpful to engineer crop plants and improve transgenic crops for stress tolerance. In this review, we focused on a new perspective on transcriptional factors to regulate functional genes of cuticular wax biosynthesis in plants at abiotic stresses.

Soil salinity is an increasing threat to the productivity of glycophytic crops worldwide. The root plays vital roles under various stress conditions, including salinity, as well as has diverse functions in non-stress soil environments. In this review, we focus on the essential functions of roots such as in ion homeostasis mediated by several different membrane transporters and signaling molecules under salinity stress and describe recent advances in the impacts of quantitative trait loci (QTLs) or genetic loci (and their causal genes, if applicable) on salinity tolerance. Furthermore, we introduce important literature for the development of barriers against the apoplastic flow of ions, including Na+, as well as for understanding the functions and components of the barrier structure under salinity stress.

Silicon (Si), a beneficial element for plants, is known for its prophylactic effect under stress conditions. Many studies have documented the role of biogenic silica (bulk-Si) in alleviating biotic and abiotic stresses in plants. The scarce amount of the plant-available form of Si (monosilicic acid) in most of the cultivated soil and the limited efficacy of silicate fertilizers (bulk-Si) are the major concerns for the exploration of Si-derived benefits. In this regard, recent advances in nanotechnology have opened up new avenues for crop improvement, where plants can derive benefits associated with Si nanoparticles (SiNPs). Most of the studies have shown the positive effect of SiNPs on the growth and development of plants specifically under stress conditions. In contrast, a few studies have also reported their toxic effects on some plant species. Hence, there is a pertinent need for elaborative research to explore the utility of SiNPs in agriculture. The present review summarizes SiNP synthesis, application, uptake, and role in stimulating plant growth and development. The advantages of SiNPs over conventional bulk-Si fertilizers in agriculture, their efficacy in different plant species, and safety concerns have also been discussed. The gaps in our understanding of various aspects of SiNPs in relation to plants have also been highlighted, which will guide future research in this area. The increased attention towards SiNP-related research will help to realize the true potential of SiNPs in agriculture.

Drought and zinc (Zn) deficiency are serious biotic stress factors that restrict plant growth and agricultural production in arid and semi-arid regions, especially when they take place concurrently...

The research was carried out in 2017-2019 in the conditions of the Smolensk region on sod-podzolic medium loamy slightly acidic soil. The study included 25 varieties and lines of fiber flax of domestic and foreign selection. The mid-ripening variety Impuls (Russia) was used as a standard, whose yield, depending on the test year, was 1.07...1.29 t/ha. As shown by the calculations of the index of environmental conditions, the most favorable conditions for fiber flax developed in 2018 (Ij = +0.46), and stress conditions, caused by excessive moisture during the critical period of plant growth and development (GTC = 1.7), in 2017 (Ij = -0.55). On average, over the years of research, the yield of fiber, depending on the genotype, varied in the range of 1.00...1.97 t/ha. The highest yield on average for three years of testing (1.78...1.97 t/ha) and average yield in contrasting conditions were characteristic of the varieties Cesar, Sinel, Dobrinya (Russia), Marylin (Holland), Andrea, Altea (France). Under favorable weather conditions (2018), a high potential for the yield of flax fiber compared to the average value (121.5...133.3 %) was obtained in the varieties Cesar, Dobrinya, Sinel (Russia), Belita (Belarus), Andrea, Altea (France), Marylin (Holland). Under stressful conditions (2017), high adaptability was found in the samples of the Russian selection Cesar (173.4 %), Sinel (168.0 %), Dobrinya (151.1 %), Tost 3 (128.7 %), Alfa, Universal (127.7 %). The varieties Surskiy (bi = 2.2), Belita (Belarus), l. 323-02 (Russia), Marylin (Holland) − 1.7, Alexandrit (Russia), Andrea (France) – 1.5. Were characterized by high responsiveness to cultivation conditions (bi> 1). Russian varieties with a relatively stable yield: Cesar, Sinel – 0.7, Alpha – 0.6, Lider, Smolich, Tost 3, Universal – 0.5, Impuls – 0,2 did not show reaction to changes in growing conditions (bi

Non-invasive methods for detecting plant stress conditions are a method for registering chlorophyll fluorescence, including measurement of induction and spectral analysis of fluorescence, and a method for spectral analysis of radiation reflected from leaves. Existing portable devices allow you to measure only one of these parameters. (Research purpose) The research purpose is in developing a combined portable device for detecting plant stress conditions by recording the reflective characteristics of leaves, the spectrum, and the induction of chlorophyll fluorescence. (Materials and methods) Authors developed a laboratory sample of the device for determining the stress states of plants and tested it on plants of garden basil (Ocimum basilicum) lemon varieties, while some plants were exposed to a stress factor in the form of ultraviolet C-radiation. Authors analyzed the fluorescence spectrum of chlorophyll when excited by various radiation sources and the back reflection spectrum when irradiated with a halogen lamp. (Results and discussion) The influence of the stress factor is manifested in a change in the shape of the fluorescence spectrum, namely, in a decrease in the intensity of fluorescence in the long-wave part of the spectrum. the reflectivity in the green and far red regions of the spectrum also decreases, and the steepness of the graph decreases when moving from the red to the far red region. (Conclusions) To register the fluorescence spectrum of chlorophyll, the best option for excitation is the use of lasers with wavelengths in the range of 405÷470 nanometers. It is possible to combine the functions of spectral analysis of chlorophyll fluorescence and radiation reflected from leaves in one device, which can improve the accuracy of determining the stress states of plants.

The equivalent strength and stiffness of geosynthetic-encased soil are two important parameters for analysis of cellular geosynthetic-reinforced foundations and earth structures. However, limited analytical approaches exist for the estimation of these parameters, and this limitation hinders their applications in geotechnical engineering practice. In this study, an analytical method is proposed for the prediction of the stress-strain response of geosynthetic-encased soil by employing the soil response in the triaxial stress condition and the theory of thin cylinders. This method has the advantages of theoretical rigorousness and convenience for use and can consider soil nonlinearity, soil dilatancy, soil plasticity and soil-geosynthetic interaction. Different types of yield criteria for soils can be readily incorporated into the proposed method. The proposed method is validated against the results of triaxial compression tests on geosynthetic-encapsulated sand. The good agreement between the predicted stress-strain curves and the measured curves demonstrates the effectiveness of the method. In addition, design tables and parametric studies are provided by employing the formulated analytical method for application purposes.

The presence and distribution of fractures in a fractured rock play a vital role in its stress state and variability. Understanding the stress condition is also one of the most important aspects of rock mechanics and geomechanical studies. In this study, we attempted to determine the influence of fracture distribution and interaction between fractures on the dispersion of stress perturbation by employing a discrete fracture network formulation. To do so, at first, a discrete fracture network was generated using a stochastic approach. Then, under technical stress loading conditions, in two different scenarios, the stress field was computed by a finite difference software. Finally, obtained stress data were analyzed using tensor-based formulations. The results showed that stress perturbation and stress dispersion (which was evaluated using effective variance) were affected by the fracture distribution in two different fracture network models, including the typical and conditional fracture network. The values of effective variance in conditional fracture networks (where there is no connection between the fractures and the fractures have no interaction with each other and are scattered in different parts of the model) is higher than the typical model. This is due to the reason that in the typical model, because of the connection, interaction, and intersection between fractures, the model is a more consolidated fracture network system. Therefore, less dispersion occurs in the stress distribution.

While cyclic triaxial (CTX) tests are widely used in liquefaction studies due to their simplicity, direct simple shear (DSS) tests and their ilk (e.g., the combined triaxial simple shear, TxSS) are more representative of stress conditions produced during an earthquake. Therefore, the CTX results should be properly correlated to simulate field conditions. In the current study, a series of CTX testing results performed on reconstituted samples of Baie-Saint-Paul, Ottawa C-109, and Quebec CF6B sands are compared to the corresponding TxSS and DSS results under both stress- and strain-controlled conditions. The cyclic TxSS stress-controlled tests are numerically simulated by adopting a coupled energy-based pore water pressure model using the computer code, FLAC. The TxSS numerical results are successfully compared with those obtained experimentally from (1) alternative stress-controlled TxSS, (2) available liquefaction potential curves (CSR-Nliq) in the literature, and (3) stress-controlled DSS testing results. As anticipated, the outcomes of the cyclic stress-controlled CTX testing results in the form of liquefaction potential curves are usually higher than that of the TxSS testing results. In contrast, due to the difference in the applied (strain-controlled tests) and the induced (stress-controlled tests) strains, the liquefaction resistance curves of TxSS are higher than those of CTX under cyclic strain-controlled test.

In engineering, it is considerably important to understand the evolution process of sandstone deformation and permeability under complex stress conditions. Although numerous scholars have reported on sandstone permeability, many of their studies are only based on uniaxial or conventional triaxial stress conditions. In practical engineering, in situ stress evidently indicates three-dimensional anisotropy. In recent years, many scholars have performed experimental studies on rock permeability under true triaxial stress. There are, however, few investigations related to the influence of intermediate principal stress and intermediate principal stress coefficient on sandstone permeability; moreover, the mechanism is unclear. In this study, the permeability of sandstone under true triaxial stress conditions is measured using a true triaxial apparatus. The results show that the intermediate principal stress has significant effects on permeability and deformation of sandstone sample. Under different principal stress conditions, the permeability is observed to decrease with the increase of the principal stress. With increasing intermediate principal stress coefficient b (from 0 to 1), the major principal strain and the minor principal strain always compressed and finally decreased by 27.31 and 36.96%, while the intermediate principal strain finally changes from expansion to compression (from − 0.045 to 0.255%). Also the normalized permeability loss increased from 9.57 to 16.59%. In addition, by fitting the experimental data with several permeability models, it was found that a true triaxial permeability model can well describe the changes in sandstone permeability. Based on the fitting parameters, the influence of intermediate principal stress and its coefficient on the stress sensitivity of sandstone was analyzed.

Endophytic fungi reside within the plant tissues and maintain a strong symbiotic relationship. They are of utmost importance as promising sources of chemically diverse bioactive natural products. These microbes alter gene expression levels, modulate biosynthetic pathways, mitigate stressful conditions in plants and thereby play an important role in establishing plant's defence system against potential pathogens. The quest for discovering new chemical entities of pharmaceutical importance has drawn attention towards the mangrove ecosystem, which offers unique biodiversity. Mangroove associated fungi live under stress conditions and are the potential source of chemically diverse metabolites. Some fungal metabolites served as lead molecules for the development of new anti-infective agents. These fungi were modified/tailored using epigenetic means or culture optimization methods to improve the yield of useful metabolites. The present review describes the compounds isolated from mangrove endophytic fungi during 2013–2019 (up to June 2019) with focus on their chemical structure and their anti-infective activity. The compounds identified from endophytic fungi are arranged based on their antibacterial, antimycobacterial, antifungal, and antiviral activities.

Using in situ nanomechanical testing under high-resolution transmission electron microscope, we reveal that the grain boundary at the twin-twin interaction region (referred to as GBT) can either migrate via a shuffling process to contribute to the dislocation transmission or facilitate the dislocation cross-slip between the two intersected twins. Stress condition, energy barrier and geometric structure of the GBT can influence these two modes of dislocation activities at the intersection region. Besides, the dislocations inside the incoming twin can traverse the GBT by dislocation-GBT reactions. These findings should have general implications to the understanding of the deformation of nanotwinned materials.

The intertidal marine periwinkle, Littorina littorea, have developed various strategies to deal with cyclic exposures to anoxic and/or freezing stresses when out of water at low tide. With promising translational research potential, evolutionarily conserved microRNAs (miRNAs) have recently become a focus of animal stress response studies. Using RNA-seq, the current study explores the conserved hepatopancreas miRNAs in facilitating snail stress survival. Overall, stress-specific miRNA responses were overserved. Anoxia led to substantial differential miRNA expression patterns, whereas freezing stress showed a relatively high degree of individual variance in miRNA expression. Pathway analysis identified miRNA-related stress survival adaptations, such as cell proliferation. Additionally, machine learning-based gene selection identified seven hepatopancreas miRNAs critical to distinguish between snails under either stress conditions. Our study demonstrated that conserved miRNAs reflect survival adaptations by marine periwinkles under anoxic or frozen conditions, and thus further establishes these snails as an optimal stress model suited for translational research.

The DNA-binding protein Dps plays a key role in the formation of Dps–DNA crystalline arrays in living bacterial cells, which allows bacteria to survive under stress conditions and under the influence of various adverse factors. Such genome-protective mechanisms can lead to the emergence of bacterial resistance to antibiotics and other drugs. Elucidation of the fundamental biochemical, genetic, and structural basis of the resistance is of primary importance for the development of strategies for combating and preventing bacterial resistance, as well as the elaboration of innovative therapeutic approaches. Conformational characteristics of Dps and its N-terminal fragments responsible for the nature of interactions of this protein with DNA in solution were studied by small-angle scattering.

A highly rapid, specific, and simple quantitative proton nuclear magnetic resonance (1H-qNMR) method was established for quantification of a novel anti-coagulant drug; betrixaban maleate (BET) in i...

Mitochondrial heat shock proteins of HSP70 family support protein homeostasis in mitochondria under normal and stress conditions. They provide folding and complex assembly of proteins encoded by mitochondrial genome, as well as import of cytosolic proteins to mitochondria, their folding and protection against aggregation. There are reports about organ-specificity of mitochondrial HSP70 synthesis in plants. However, tissue specificity of their functioning remains incompletely characterized. This problem was studied for mitochondrial AtHSP70-10 in Arabidopsis thaliana seedlings using a transgenic line with uidA signal gene under normal conditions, as well as high temperature and water deficit. Under normal conditions, histochemical GUS-staining revealed the expression of AtHSP70-10 in cotyledon and leaf hydathodes, stipules, central cylinder in root differentiation and mature zones, as well as weak staining in root apex and root-shoot junction zone. RT-PCR analysis of wild-type seedlings exposed to 37°C showed rapid upregulation of AtHSP70-10, which reached the highest level within 2 h. In addition, the gradual development of water deficit for 5 days caused an increase in transcription of this gene, which became more pronounced after 3 days and reached a maximum after 5 days of dehydration. Histochemical analysis showed complete preservation of tissue localization of AtHSP70-10 expression under both abiotic factors. The data obtained indicate the specific functioning of mitochondrial chaperone AtHSP70-10 in certain plant cellular structures.

To investigate the influence of loading rate on rockburst in a circular tunnel under three-dimensional stress conditions, the true-triaxial tests were conducted on 100 mm×100 mm×100 mm cubic sandstone specimens with d50 mm circular perforated holes, and the failure process of hole sidewall was monitored and recorded in real-time by the microcamera. The loading rates were 0.02, 0.10, and 0.50 MPa/s. The test results show that the rockburst process of hole sidewall experienced calm period, pellet ejection period, rock fragment exfoliation period and finally formed the V-shaped notch. The rockburst has a time lag and vertical stress is high when the rockburst occurs. The vertical stress at the initial failure of the hole sidewall increases with loading rate. During the same period after initial failure, the rockburst severity of hole sidewalls increased significantly with increasing loading rate. When the vertical stress is constant and maintains a high stress level, the rockburst of hole sidewall under low loading rate is more serious than that under high loading rate. With increasing loading rate, the quality of rock fragments produced by the rockburst decreases, and the fractal dimension of rock fragments increases.

Lipocalins are very important proteins for stress resistance in plants. To better understand the function of tomato lipocalins, we observed responses to oxidative stress using over-expressed SlTIL1, SlTIL2, SlCHL, and silenced-plants. Significant differences in reactive oxygen species accumulation (oxidative damage) were observed in all tested plants under heat stress. Plants with over-expressed SlTIL1, SlTIL2, and SlCHL showed less oxidative damage compared with wild-type plants under heat stress. The expression of SlSODs was induced in over-expressed SlTIL1, SlTIL2, and SlCHL plants under normal and heat stress conditions. Furthermore, silenced PDS, SlTILs, and SlCHL plants showed slightly increasing oxidative damage under heat stress alongside with lower SlSODs under normal and stress conditions. These results suggest that SlTIL1, SlTIL2, and SlCHL were involved in antioxidant defense by eliminating ROS in tomato plants.

Abscisic acid (ABA) although complicated and expensive to produce, plays an important role in signalling responsible for regulation of developmental manifestations such as seed maturation and surviving through stress conditions. Hence, development of cost effective molecules with minimal side effects that mimic the functions of ABA is the need of the hour. In this agreement, we screened a series of 27 in-house synthesized 3-methyleneisoindolin-1-one molecules over three ABA receptors (PYR1, PYL1, and PYL3). The commercial ABA agonist Pyrabactin was taken as a standard ligand in this study. The top three molecules for each receptor were selected and further evaluated to estimate the dynamical contribution and complex stability via Molecular Mechanics-Poisson Boltzmann surface area calculations. Two molecules (Mol26 and Mol25) showed higher binding free energy and stable complex conformation for PYL3 in comparison to Pyrabactin. This study revealed the structural basis of the binding mechanism of 3-methyleneisoindolin-1-one molecules with ABA receptors. Mol26 and Mol25 were identified for the development of specific PYL3 agonists with a vast potential in agriculture to accentuate the ABA like action in plants.

Pre-conditioning by hydraulic fracturing is a vital work in block caving mining of hard-rock metal mine, and breakdown pressure is one of the important parameters in rock hydraulic fracturing process, which determines the equipment selection and job-parameter control. Based on numerical simulation method, a pre-holed cylindrical hard rock sample was built for simulation of hydraulic fracturing process to investigate the effect of stress condition, rock properties and water injection rate on breakdown pressure. The results show that the breakdown pressure is increased with the confining stress, and the breakdown pressure is 2.28 times confining stress based on rock tension strength. The variation of rock tension strength affects the breakdown pressure and a positive linear relation exists. Pre-formed notch could obviously reduce the breakdown pressure and control the orientation of hydraulic fracture. And the borehole diameter has a reverse influence on rock breakdown pressure.

In this brief, typical locations of the interface and oxide traps generated by the hot carrier degradation (HCD) in FinFETs are studied with experiments and “atomistic” TCAD simulations under the worst case stress conditions. The typical round-Fin locations of different types of traps are analyzed by comparing the experimentally extracted results with the calibrated TCAD simulations. Then, the traps’ different impacts on HCD variations in both forward and reverse bias modes are employed to disclose the typical lateral locations of different traps. The results suggest that for both n- and p-type of FinFETs under the worst case stress conditions, the interface traps and oxide traps (type 1) are mainly distributed in the midchannel region closer to the source side on the Fin side, whereas oxide traps (type 2) are mainly distributed in the midchannel region closer to the drain side on the Fin top. Therefore, the two types of oxide traps originate in the different generation locations but may share the same atomistic structures in the same device. The results are helpful to the physical understandings of HCD in the FinFET technology.

In this study, the root exudates of wetland plants, Pistia stratiotes, black algae, and Cyperus alternifolius, exposed to six phosphorus concentration gradients (0, 0.2, 1, 5, 10, and 20 mg/L) were characterized. The experimental seedlings were cultivated in Hoagland solutions, which were then extracted, decompressed, and concentrated with CH2Cl2; subsequently, a gas chromatography-mass spectrometry (GC-MS) analysis was performed to study the root exudates effects under different phosphorus concentrations. Results showed the existence of several organic compounds, such as alkanes, esters, alcohols, amines, benzene, and acids (phthalic acid, cycloheptasiloxane, benzoic acid, and cyclopentasiloxane) in the root exudates of the wetland plants. The relative contents of phthalate, benzene dicarboxylic acid, and cyclohexasiloxane in the root exudates first increased, and then decreased, with the change in phosphorus concentration. The relative contents of three compounds in Pistia were the highest at 1 mg/L of phosphorus, and the lowest relative contents of phthalic acid and benzene dicarboxylic acid were observed at 20 mg/L of phosphorus. However, the relative content of cyclohexasiloxane was the lowest in the absence of P stress. In black algae, the relative contents of the three compounds were 36.66, 16.24, and 14.61%, respectively. The relative content of cyclohexasiloxane in the black algae first decreased and then increased, with its lowest relative content occurring at 5 mg/L of phosphorus and the highest at 10 mg/L of phosphorus. In Cyperus alternifolius, the highest relative concentrations of the four compounds: phthalic acid, dimethyl phthalate, octadecane, and diphenyl sulfone in Cyperus were observed at 5 mg/L phosphorus and the lowest at 10 mg/L phosphorus.

The influence of heat treatment processes, which consist of a quenching partitioning (QP) process, intercritical annealing (IA) process and warm rolling (WR) process, on the hydrogen embrittlement (HE) of medium Mn steels is investigated. The corresponding experimental specimens are labeled QP160, IA810 and WR760, respectively. WR760 reveals the best mechanical properties, and the corresponding product strength and elongation (PSE) is 42.9 GPa•%; nevertheless, HE susceptibility is the lowest due to fine grains and microcrack propagation paths, which are parallel to rolling direction (RD), and they relax the triaxial stress conditions ahead of the main transverse crack's tip. IA810 (PSE = 29.1 GPa•%) shows the highest HE susceptibility due to the extremely unstable γ, which makes the microcrack propagation along the interface of γ(α′)/α-ferrite occur more easily when there is hydrogen. Compared to IA810, QP160 (PSE = 17.6 GPa•%) reveals a lower HE susceptibility due to the higher γ stability.

Stomata polymorphism in leaves of apple trees (Malus domestica) growing under mountain and plain conditions has been studied using scanning electron microscopy. The leaves of this species were hypostomatic with anomocytic stomata and radially diverging cuticular folds combined into bundles (cuticular bundles), the number of which usually corresponded to the number of epidermal cells surrounding the stomata. The average size of stomata increased linearly as the number of cuticular bundles increased. Under favorable conditions (600-m altitude above sea level), a high density of rounded stomata was observed. Stress conditions, such as high temperatures and droughts on the plain (300-m altitude) or high insolation and temperature drops in the mountains (1200-m altitude), provided the same effect on the micromorphology of the leaf surface, while the effect of altitude was manifested in the reduction of the size of epidermal cells.

Two-high and three-high screw rolling of stainless-steel billets was conducted. Experimental rolling was simulated using DEFORM software. Differences in the way hardness, Cockroft–Latham normalized damage criterion, and rigidity coefficient under stress condition change while two-high and three-high screw rolling were established. Changing of these parameters was investigated in the cross section of the billets at the stationary stage of screw rolling. It was unambiguously shown that, in terms of conducted experiments, there is a tendency for axial fracture while two-high screw rolling, and for ring-shaped fracture while three-high screw rolling. Research has allowed for quantitatively estimating the value of the radius of ring-shaped area for which possible fracture may occur while three-high screw rolling.

In deep underground engineering, understanding of time-related stress memory properties is critical to evaluate the in situ stress conditions of a rock mass. In this study, the time-sensitivity mechanism of the rock stress memory properties under tensile stress was investigated. It was found that the material property (Poisson's ratio) and crack angle were the controlling factors of the Kaiser effect (KE) under tensile stress. In particular, the time-sensitivity of the stress memory properties was closely related to the crack growth path. When the failure of the rock specimen was dominated by tensile microcracks and the crack development direction was deflected by up to 30° in the successive loading process, the stress memory capacity was likely to be time-independent for a sandstone specimen. The distribution of the Felicity ratio in a Brazilian test was more discrete than that in a three-point bending test. It also showed that the changes in the crack path, rather than the time interval between successive loading cycles, led to inaccuracy of the detected KE. This study provides insights into stress memory-related issues under uniaxial or more complex stress conditions and thus facilitates development of methods for testing in situ mechanical behaviors of rocks with acoustic emission (AE) technology.

Alternative splicing (AS) plays crucial roles during plant development especially in stress responses. Although many studies have been performed on AS, the function of which participating in abiotic stress responses is still not well known. To assess the interplay between AS and salt stress, genome-wide analyses of AS were performed. Totally, 11,141 genes were found exhibiting significant AS changes after salt stress treatment, and more AS events were identified in Chinese Spring (CS, salt-sensitive) (21,203) than in Qing Mai 6 (QM, salt-tolerant) (19,742). Meanwhile, wheat homeologous genes displayed differential AS responses under salt stress treatment, and 7235, 8143 and 7407 AS events were identified on subgenome A, B and D respectively. Comparison of AS events at different time after salt stress showed that 4747 and 4129 salt stress responsive AS events were characterized in CS and QM, respectively, and most AS events were induced at 48 h after salt stress (HAS) compared with the other three stages. Functional enrichment analysis found that abiotic stress responsive pathways tended to be enriched in partitioned differentially spliced genes (DSGs) between CS and QM after salt stress treatment, and Pfam classification showed that many stress related proteins were also enriched under salt stress condition. Thus, these results demonstrated that AS regulation may play key roles in response to salt stress, which, together with transcriptional regulation, contributes to abiotic stress tolerance in wheat.

Rock stress memory, often referred as Kaiser effect, in rocks can be an effective tool to estimate the in situ stress conditions, if the uncertainties in rock damage and its behavior during loading conditions are properly understood. In view of this, the present study is an attempt to investigate the variations in rock stress memory, i.e., the Kaiser effect in a metamorphic rock under multi-stage uniaxial compression. The khondalite rock samples from Eastern Ghats Mobile Belt (EGMB) belonging to southeastern part of Indian subcontinent having complex geological history are examined. The effects of multi-stage compression on the damage evolution and subsequent variations in rock stress memory are investigated. The samples were categorized into different levels of rock stress memory, depending on the stress the rock was able to withhold after loading stages. The damage evolution in the tested rocks was predominantly controlled either by initial loading or failure stress. Higher damage imparted by initial loading and intense fracturing could be the possible reason for poor stress memory function in the investigated rock. Felicity ratio, an indicative of rock damage with stages of loading, supported the observation that rock damage was dominant during initial loading stage. Rock heterogeneity has played a dominant role in decay of Kaiser effect, with intense fracturing during subsequent loading stages in the investigated rocks. To summarize, Kaiser effect can be used to infer rock damage and stress conditions, provided the geological history of the region is also taken into consideration. With rocks from complex geological conditions, Kaiser effect or rock stress memory should be supported by other tools to infer in situ stress, but the method can be effectively used to understand the stress changes and damage mechanism of multiple loading.

Direct shear tests on rocks under compression–shear stress conditions have been widely conducted, whereas few have been performed under tension–shear stress conditions. However, rocks exhibit tension–shear failures in many scenarios, such as in the excavation disturbed zone in deep underground caverns and high slopes. A series of direct shear tests were performed with cuboid sandstone specimens under different normal tensile stresses (σn = − 3, − 2, and − 1 MPa) and compressive stresses (σn = 1, 3, and 5 MPa) at different shearing rates (v = 0.2, 1, 5, and 10 mm/min). The tension–shear tests were performed using an auxiliary device in combination with a compression–shear testing machine. The results showed that the fracture, shear stress–displacement curve, shear stiffness and shear strength were affected by both σn and v, and the differences in these mechanical behaviour between compression–shear and tension–shear cases were analysed in detail. The shear strength had a nonlinear relationship with both σn and v in the full region of tested normal stress (namely, the normal stress range from tension to low compression). The Hoek–Brown criterion $$(\tau = A(\sigma_{{\text{n}}} - \sigma_{{\text{t}}} )^{B} )$$ considering the shearing rate effect (the relationship between parameter A (B) and shearing rate v is represented by a natural logarithm function) was proposed as the optimal shearing rate-dependent strength criterion for sandstone in the tested normal stress range.

In nature, plants are regularly exposed to biotic and abiotic stress conditions. These conditions create potential risks for survival. Plants have evolved in order to compete with these stress conditions through physiological adjustments that are based on epigenetic background. Thus, the ecological signals create different levels of stress memory. Recent studies have shown that this stress-induced environmental memory is mediated by epigenetic mechanisms that have fundamental roles in the aspect of controlling gene expression via DNA methylation, histone modifications and, small RNAs and these modifications could be transmitted to the next generations. Thus, they provide alternative mechanisms to constitute stress memories in plants. In this review, we summarized the epigenetic memory mechanisms related with biotic and abiotic stress conditions, and relationship between priming and epigenetic memory in plants by believing that it can be useful for analyzing memory mechanisms and see what is missing out in order to develop plants more resistant and productive under diverse environmental cues.

To investigate the influence of indentation rate on the fracture characteristics, first laboratory indentation tests were performed. The laboratory tests show that the peak indentation force increases with the increase in the indentation rate. However, the increase in indentation rate restrains the crack propagation. Then, numerical indentation tests, using PFC 2D, were conducted to verify the laboratory results. For the crack propagation and the peak indentation force, the numerical and laboratory results are consistent. To further study the underlying mechanism, the stress conditions before and after the median crack propagation were analyzed. The results shows that the increase in indentation rate significantly promotes the fracture toughness and thus restrains the crack length.

In vascular plants, lignin is deposited during morphogenesis but also under stress conditions. Assessing the degree of stress-induced lignin deposition is complicated because it occurs locally and irregularly in plant tissues. In this study, we developed a macro program, LigninJ, for the open-source software ImageJ to automatically and efficiently determine areas and levels of lignification after Wiesner (phloroglucinol-HCl) staining. We used the CIELAB color space for detection of red color following the Wiesner reaction. In addition, LigninJ has a function for adjusting the background level and its white balance to reduce biases that are inherent to individual color images. Furthermore, LigninJ can be used for batch analyses of multiple images, taking about 2 s per image. In this study, we analyzed wound-induced lignin deposition in cotyledons of the Arabidopsis thaliana ecotypes Landsberg erecta and Columbia and assessed ectopic lignin depositions in roots of lignescence (lig) mutants of Arabidopsis. Our results confirmed that this method is efficient for evaluating the degree of stress-induced lignin deposition.