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In the present scenario, growing population demands more food, resulting in the need for sustainable agriculture. Numerous approaches are explored in response to dangers and obstacles to sustainable agriculture. A viable approach is to be exploiting microbial consortium, which generate diverse biostimulants with growth-promoting characteristics for plants. These bioinoculants play an indispensable role in optimizing nutrient uptake efficiency mitigating environmental stress. Plant productivity is mostly determined by the microbial associations that exist at the rhizospheric region of plants. The engineered consortium with multifunctional attributes can be effectively employed to improve crop growth efficacy. A number of approaches have been employed to identify the efficient consortia for plant growth and enhanced crop productivity. Various plant growth-promoting (PGP) microbes with host growth-supporting characteristics were investigated to see if they might work cohesively and provide a cumulative effect for improved growth and crop yield. The effective microbial consortia should be assessed using compatibility tests, pot experimentation techniques, generation time, a novel and quick plant bioassay, and sensitivity to external stimuli (temperature, pH). The mixture of two or more microbial strains found in the root microbiome stimulates plant growth and development. The present review deals with mechanism, formulation, inoculation process, commercialization, and applications of microbial consortia as plant bioinoculants for agricultural sustainability. [ABSTRACT FROM AUTHOR]

A new area of biotechnology is nanotechnology. Nanotechnology is an emerging field that aims to develope various substances with nano-dimensions that have utilization in the various sectors of pharmaceuticals, bio prospecting, human activities and biomedical applications. An essential stage in the development of nanotechnology is the creation of nanoparticles. To increase their biological uses, eco-friendly material synthesis processes are becoming increasingly important. Recent years have shown a lot of interest in nanostructured materials due to their beneficial and unique characteristics compared to their polycrystalline counterparts. The fascinating performance of nanomaterials in electronics, optics, and photonics has generated a lot of interest. An eco-friendly approach of creating nanoparticles has emerged in order to get around the drawbacks of conventional techniques. Today, a wide range of nanoparticles have been created by employing various microbes, and their potential in numerous cutting-edge technological fields have been investigated. These particles have well-defined chemical compositions, sizes, and morphologies. The green production of nanoparticles mostly uses plants and microbes. Hence, the use of microbial nanotechnology in agriculture and plant science is the main emphasis of this review. The present review highlights the methods of biological synthesis of nanoparticles available with a major focus on microbially synthesized nanoparticles, parameters and biochemistry involved. Further, it takes into account the genetic engineering and synthetic biology involved in microbial nanobiosynthesis to the construction of microbial nanofactories. [ABSTRACT FROM AUTHOR]

Heavy metal pollution is one of the modern environmental problems that contaminate soil, water, and air. Heavy metal pollution not only results in significant crop yield losses, but also poses health risks. When subjected to heavy metal toxicity, which happens when the quantity of particular heavy metals in the soil or water exceeds their tolerance levels, plants can exhibit a variety of reactions. Metal accumulation in the tissues of plants causes oxidative stress. The oxidative stress in turn impacts cellular homeostasis and adversely affects growth and development. Plants exhibit different mechanisms to fight stressful conditions and lessen the negative consequences of heavy metal toxicity. In this regard, the first line of defence in response to heavy metal toxicity provided by the plant is restricting the uptake of the metals. The second line of defence includes various detoxification mechanisms. Microbes especially associated with the rhizospheric region of the crops have role in remediation of the soils from metal contaminants. The present review highlights the impact of heavy metal on plants and role of the microbes in lessening of heavy metal stress in plants. [ABSTRACT FROM AUTHOR]

The present research work is primarily carried out to select the suitable and better variants or functions of ETAS models to describe the energetic offshore earthquake swarms following 26 December 2004 (MW 9.1) and 21 March 2014 (MW 6.5) along the Andaman–Sumatra subduction zone. An attempt has also been made to inspect the variability of the selected model parameters from this robust estimation to discuss the physical mechanism differences between the SSE-related and fluid- or magma-related swarm sequences. For this purpose, different variants of ETAS models, such as single ETAS model, combined ETAS model, Boxcar swarm model, and exponential swarm model, are utilized for investigating the seismic anomalies by estimating the model parameters from the earthquake occurrence times using maximum likelihood method. The estimated AIC (Akaike information criterion) values for all these models suggest that the exponential swarm model outperforms the other models in successfully explaining the transient changes of background seismicity for the five energetic earthquake swarms triggered by the volcano-tectonic activities in the Andaman Sea. The reason is undoubtedly related to the localized nature of magmatic intrusion or fluid migration that caused the swarms and the exponential decay patterns of earthquakes after the initiation of the swarms. Although the swarms exhibit the shape of exponential function, the background seismicity shown by the parameter μ increases by one order during the swarm as compared to the pre-swarm period in the sub-catalogue. Therefore, the procedure of identifying improved variants or functions of ETAS models and estimating model parameters using earthquake occurrence times enhances our understanding of earthquake-triggering mechanisms, potential swarm activity patterns, and the intricate interplay between seismicity and volcanic processes in submarine volcanic arcs. While this approach might not facilitate real-time forecasting, it remains instrumental in characterizing seismic patterns and providing essential information for effective hazard assessment and the formulation of mitigation strategies within the coastal areas of the Andaman–Nicobar Islands region. [ABSTRACT FROM AUTHOR]

Endophytic microbes are plant-associated microorganisms that reside in the interior tissue of plants without causing damage to the host plant. Endophytic microbes can boost the availability of nutrient for plant by using a variety of mechanisms such as fixing nitrogen, solubilizing phosphorus, potassium, and zinc, and producing siderophores, ammonia, hydrogen cyanide, and phytohormones that help plant for growth and protection against various abiotic and biotic stresses. The microbial endophytes have attained the mechanism of producing various hydrolytic enzymes such as cellulase, pectinase, xylanase, amylase, gelatinase, and bioactive compounds for plant growth promotion and protection. The efficient plant growth promoting endophytic microbes could be used as an alternative of chemical fertilizers for agro-environmental sustainability. Endophytic microbes belong to different phyla including Euryarchaeota, Ascomycota, Basidiomycota, Mucoromycota, Firmicutes, Proteobacteria, and Actinobacteria. The most pre-dominant group of bacteria belongs to Proteobacteria including α-, β-, γ-, and δ-Proteobacteria. The least diversity of the endophytic microbes have been revealed from Bacteroidetes, Deinococcus-Thermus, and Acidobacteria. Among reported genera, Achromobacter, Burkholderia, Bacillus, Enterobacter, Herbaspirillum, Pseudomonas, Pantoea, Rhizobium, and Streptomyces were dominant in most host plants. The present review deals with plant endophytic diversity, mechanisms of plant growth promotion, protection, and their role for agro-environmental sustainability. In the future, application of endophytic microbes have potential role in enhancement of crop productivity and maintaining the soil health in sustainable manner. [ABSTRACT FROM AUTHOR]

Agriculture is the backbone of developing countries, which plays an essential role in primary drivers of economy. The increasing use of chemical fertilizers and toxic insecticides endangers the health of human, plant soils, and the environment. Microbial insecticides have been implemented in current scenario for crop protection. Biological agents for pest control have gained more attention in recent year as substitutes for management of pests and pathogens. It provides a sustainable approach to plant health management and assists to minimize the excessive applications of toxic substances. The antagonistic microbes belong to six different phyla including Bacillota, Actinomycetota, Pseudomonadota, Bacteroidota and Mucoromycota. Microbial pesticides have been developed through a number of processes, including extraction of pure culture and screening using effectiveness bioassays under controlled and natural conditions. Biological control agents (BCAs) are recognized to be the most sophisticated technology for environmentally friendly agriculture. The various beneficial BCAs have been reported for the management of plant health, but they required effective acceptance together with the standardization of bioformulation. The present review deals with the recent development of microbial control agents, mechanisms of actions, development of microbial pesticides and their potential applications for agricultural productivity. [ABSTRACT FROM AUTHOR]

The leachates emanating from the landfills are high in organic loads and thus become potential sources of contamination for both surface and groundwater. As the landfill ages, the nature of leachate changes from acidic to alkaline. The change in pH level affects the chemical oxygen demand (COD)/biochemical oxygen demand (BOD) ratio and when it is less than 0.63, chemical treatments are more effective over the biological treatment methods such as upflow anaerobic sludge blankets (UASB). The existing literature suggests coagulation–flocculation and advanced oxidation process (Fenton) as effective methods for treating wastewater but no comparison of the two are available. Thus, the present study attempts to identify the most efficient coagulants out of ferric chloride (FeCl3), ferrous sulphate (FeSO4) and alum [Al2(SO4)3]. Ferric chloride leading to 99% colour removal, 98% COD removal, 99% decrease in total organic carbon, 94.3% removal in NH3–N and 91.4% removal in total Kjeldahl nitrogen is observed to be the most efficient coagulant and surprisingly, proves to be even better than Fenton. To understand the field applicability of the two treatment procedures, coagulation with FeCl3 and Fenton are compared with the UASB method which is currently employed at Gazipur landfill site, Delhi. With lesser operational cost than UASB, both FeCl3 and Fenton perform better on cost-efficiency scale. Switching from in-suit UASB method to the FeCl3 method of treatment may result in decreasing the operational cost by 71.9% and to conventional Fenton may result in decreasing the operational cost by 76.8%. [ABSTRACT FROM AUTHOR]

Isolation of seismomagnetic effect arising from the stress-induced modulations of magnetisation becomes difficult due to natural variations of magnetic disturbances. It has been critical to find out the precursory earthquake behaviour in any of the data including geomagnetic, for the last 50 years. To search seismomagnetic signals in the present study, we have analysed four earthquakes (Mw ≥ 4.9) during 2007–2011 related to Ghuttu MPGO situated in NW Himalayas, India. These four earthquakes were found to be eligible for which Ghuttu station is in the preparation zone and an index of magnetic variation (Imv), which quantifies anomalous variations of the magnetic field from geomagnetic data, has been estimated. For this endeavour, an assumption has been made considering the average of magnetic data for the quiet days in order to compare the analysis with respect to the magnetic storms. Using the magnetic data recorded at Ghuttu MPGO for the interval of nearly two months within the range of occurrence of four moderate earthquakes, the Imv has been computed. As a result, it has been observed that the proposed Imv computed is still sensitive to global magnetic disturbances as evidenced by comparing to Dst and sum Kp for the earthquakes considered in the present study. Therefore, it is summarised that the best way to isolate seismomagnetic effect is by comparing the data of pair of stations in differential mode, one located close to the area of stress built up and the other immediately outside the seismic zone, so that the background noise can be eliminated by analysing this kind of pair stations in order to achieve the goal. However, the size of the earthquake and epicentral range are also important controlling parameters to observe the seismomagnetic effects due to an earthquake in a region. [ABSTRACT FROM AUTHOR]

Several natural hazards, including earthquakes, may trigger disasters and the presence of disaster drivers further lead to the massive loss of life and property, every year around the world. The earthquakes are unavoidable, as exact earthquake prediction in terms of date, and time is difficult. However, with the advancement in technology, earthquake early warning (EEW) has emerged as a life-saving guard in many earthquake-prone countries. Unlike other warning systems (where hours of warning are possible), only a few seconds of warning is possible in the EEW system, but this warning may be very helpful in saving human lives by taking the proper action. The concept of EEW relies on using the initial few seconds of information from nearby instruments, performing basic calculations, and issuing the warning to the farther areas. A dense network or enough network coverage is the backbone of an EEW system. Because of insufficient station coverage, the estimated earthquake location is error-prone, which in turn may cause problems for EEW in terms of estimating strong shaking for the affected areas. Seismic instrumentation for EEW has improved significantly in the last few years considering the station coverage, data quality, and related applications. Many countries including the USA, Mexico, Japan, Taiwan, and South Korea have developed EEW systems and are issuing a warning to the public and authorities. Several other countries, namely China, Turkey, Italy, and India are in process of developing and testing the EEW system. This article discusses the challenges and future EEW systems developed around the world along with different parameters used for EEW. Article Highlights: This article aims to provide a comprehensive review related to the development The explicit emphasis is on the scientific development of EEW parameters The challenges and future scopes for the effective implementation of EEWS are discussed in terms of the correct location, the magnitude estimation, the region-specific use of ground motion prediction equations, communication technologies, and general public awareness [ABSTRACT FROM AUTHOR]

Hydrodynamic and heat transfer characteristics of long-term stable nanofluids are very crucial for their industrial applications. Also utilization of coils is beneficial for industries as it provides a high rate of heat transfer and is compact in size too. So, the main focus of this study is to investigate the hydrodynamic and heat transfer characteristics of long-term stable f-CNT nanofluids when flowing inside a coil-based heat exchanger. f-CNT nanofluids were prepared by utilizing modified two-step method. To analyze the effect of different parameters on hydrodynamic and convective heat transfer characteristics, f-CNT concentration, D c , and Re were varied from 0 to 0.048 vol%, 95 to 175 mm, and 2300 to 9500, respectively. According to results, f-CNT concentration, D c , and Re substantially influenced the hydrodynamic and heat transfer characteristics of f-CNT nanofluids. It was found that improvement in h (152%) was much higher than the enhancement in friction factor (49%) when f-CNT nanofluid at 0.048 vol% was flowing through the coil of 95 mm diameter. Based on the heat transfer and hydrodynamic data, performance index was evaluated. The maximum performance index was calculated ⁓ 2.5, suggesting that the utilization of helical coils and f-CNT nanofluids is an excellent choice in industrial applications. Based on the experimental data, empirical correlations have been proposed to calculate the friction factor and Nusselt number for f-CNT nanofluids when flowing inside coils of different diameters and at different f-CNT concentrations. The proposed correlations explain the present experimental data within ± 15% and ± 20%, for friction factor and Nu, respectively. [ABSTRACT FROM AUTHOR]

Groundwater withdrawal at very fast rate poses threat on existing groundwater resources in different parts of the world. This reduction in groundwater levels significantly disturbed the natural aquifer flow rate and thereby different hydrogeochemical processes, which may further impair the groundwater quality. The groundwater quality in rural area of Chhattisgarh State is degraded, and the problem of saline water poses health risk to people. In this research investigation, suitability of groundwater of Bemetara District, Chhattisgarh, India, has been evaluated for drinking purpose through water quality index (WQI) method and principal component analysis (PCA). Total 116 groundwater samples were collected during the pre-monsoon (June 2019) and post-monsoon season (December 2019) and analyzed for physicochemical parameters. Total dissolved solids ranged from 250 to 10,440 mg/L and 289 to 3583 mg/L during pre-monsoon and post-monsoon, respectively, and 55% of the total samples exceeded acceptable BIS limit in pre-monsoon, while about 66% samples exceeded in post-monsoon season. SO42− concentrations varied from 3 to 5734 mg/L during pre-monsoon and 4.5 to 2002 mg/L during post-monsoon, respectively. Total 28% samples in pre-monsoon and 18% samples in post-monsoon season exceeded the maximum permissible BIS limit (400 mg/L) of SO42− ion in the study area. On the basis of WQI, the quality of groundwater varies from "Excellent water" to "Good water" category. The groundwater of northeastern part of the district is not suitable for drinking, and therefore, it is recommended to treat this groundwater before human consumption with special reference to SO42− contamination. PCA inferred that four components are sufficient to explain the variance in chemistry of groundwater that is mainly governed by dissolution of gypsum mineral, other rock–water interaction and anthropogenic activities. Further, water quality was improved in the direction of groundwater flow in the study area, establishing a direct relationship between groundwater flow and water quality of the Bemetara District. This study provides very useful database to design sustainable groundwater management plan for the district. [ABSTRACT FROM AUTHOR]

The statistically point process model known as epidemic-type aftershock sequence (ETAS) model is employed for systematically investigating the seismic quiescence or seismic anomalies around the focal regions of large/strong earthquakes for NW Himalaya. For this propose, the model predicted the expected occurrence rates of earthquakes by estimating the model parameters from the earthquake occurrences times using maximum likelihood method, has been used. Then the exhibited relative quiescence due to decreasing occurrence rates from the modeled ones can be identified by inspecting the abnormally downward deviated plot from the extended cumulative curve of the Residual Point Process (RPP) events. Examination of such RPP events in the whole time interval exhibits significant 1.5 years and 2.0 years of relative seismic quiescence before the strong 1991 Uttarkashi (MW 6.8) and 1999 Chamoli (MW 6.6) earthquakes, respectively. Considering the optimally oriented planes of Uttarkashi earthquake, the Coulomb stress changes (ΔCFS) have been investigated to check the rate of seismicity around the focal region of Chamoli earthquake. It has been found that ΔCFS of Uttarkashi earthquake exhibits stress shadow in or near the source zone of Chamoli earthquake and eventually decreases seismicity rates due to seismic quiescence in the source zone. On the other hand, the detected quiescence and activation relative to the predicted seismicity rate are consistent with the obtained Coulomb stress to depict the associated anomalies being sensitive enough to detect a slight stress change in the study region. Henceforth, the increased or decreased seismic activity due to seismic activation or quiescence is found to be consistent with the patterns of the Coulomb's stress changes calculated on the ruptured fault planes of Uttarkashi earthquake. Hence, this ETAS model based on statistical technique can thus be incorporated with other sensitive geophysical instruments for identifying seismically quiet period not only in the seismic gaps, but also in its neighborhoods along the Himalayan range for mitigating seismic hazards due to impending great earthquakes. [ABSTRACT FROM AUTHOR]

ICP-OES is a powerful, versatile, and advanced analytical technique with excellent detection properties. Due to its extraordinary features, it has been widely employed for the analysis of a wide variety of chemical elements in the past few years with great success. It offers the least detection time, lower detection limits, broader linear dynamic range, and greater matrix tolerability as well as negligible chemical interferences. Beyond this, it can handle multiple varieties of samples including aqueous, inorganic, organic liquids, and solids as well. It comprises complex instrumental makeup which enables it to detect up to 2 to 70 elements simultaneously with great accuracy. Recent reports evidenced that this hyphenated technique has been employed in several analytical determinations including food analysis, agricultural investigations, geological studies, drug/metabolite analysis, and environmental and forensic sciences. In the present compilation, a detailed description of the fundamental principles of ICP-OES has been provided along with its various sophisticated functional components. Also, the reported applications of this technique in different fields have been discussed highlighting the basic experimental setups and outcomes by presenting the data as tables. This summarization may be helpful to analysts to get insights into the working as well as performance characteristics of this technique. [ABSTRACT FROM AUTHOR]

The recorded strong motion data in the Delhi region provide an excellent opportunity to study high-frequency decay parameter, kappa (κ) for the National Capital (Delhi) region and to further understand its implications to study the site effects characterized by different stations within the vicinity of the study region. The kappa values are estimated at 30 locations from 99 accelerograms of 19 earthquakes recorded in the Delhi region and are found to vary from place to place depending upon the controlling parameters, primarily the site characterization. The estimated average values of 'κ' lie in the range 0.0118–0.0537 s for the various locations of the region depending upon the source, path, and site characteristics of earthquakes considered in the present study. The distance dependence is found insignificant, while there is a scatter in the variation of κ values with that of magnitude which indicates that κ is more related to the site characteristic for the entire Delhi region which in turn reveals the fact of the basic criterion of the κ parameter. To affirm the total attenuation on the instruments, the site effects demonstrate the behavior of amplification to the geological exposure. It has been found that the various sites under consideration for the study area amplify between 0.6 and 7.0 Hz predominant frequency ( f peak ) and agree with the geological arrangements of the region. Based on the present study, the most vulnerable areas are the northeastern region of Delhi which lies in proximity to the flood plains of Yamuna river and alluvial deposits of younger origins of the foreland basin along with the southwestern part of Delhi capital which is comprised of the water-saturated alluvial deposits. The estimated 'κ' values are found to be correlated with those of the estimated site amplifications and are useful in strong ground motions simulation for the proper evaluation of seismic hazard to build a seismic risk resilient society. [ABSTRACT FROM AUTHOR]

Delhi, National Capital Region (NCR) of India, falls in the seismic Zone IV (Zone factor 0.24) on the seismic zoning map prepared by the Bureau of Indian Standards (BIS), and this region may experience devastating intensities in case of plausible moderate to the major earthquake in the vicinity. The strategic geological, geomorphological, and geographic characteristics make this seat of administrative power more vulnerable toward the earthquake disaster right from the ancient periods. Therefore, we study the impact of the M 6.0 earthquake sourced at Sohna fault in the neighborhood of the capital region by generating synthetic accelerograms through semiempirical envelop technique. The observed accelerograms of November 25, 2007 ( M w 4.7) earthquake have been modeled to utilize the reliability of the semiempirical approach. To analyze the actual scenario, the ground motions at the surface have been generated after the incorporation of the site effects because different soil conditions of NCR fascinate different degrees of damage in case of a destructive earthquake. As a result, the obtained peak ground acceleration (PGA) varies between 100 and 600 cm/s2, and some of the sites exhibit even higher PGA values being situated on the sediments of river-oriented plain areas and proximity of the source. The spatial distribution of estimated values of PGA and spectral accelerations at different periods show that sites in NCR like Delhi (600 cm/s2), Sonipat (633 cm/s2), Gurgaon (461 cm/s2), and Faridabad (300 cm/s2) exhibit high to severe seismic hazard in case of M 6.0 at Sohna fault and it is suggested that a population of about 4.78 million along with the infrastructure of this region is exposed to high risk. The estimated seismic exposure of the population is important to utilize the resources properly before the destructive earthquake incidence. The hazard maps for PGA and different structural periods in the NCR region reveal the level of seismic hazard and risk of the study region. These hazard maps are very helpful for administrators, stakeholders, and civil engineers to construct earthquake-resistant structures to minimize the risk generated by the future impending earthquakes. The exponential growth of the buildings, industries, businesses, etc., attracts the attention of urban area planners because of high seismic risk due to the damaging earthquakes, and its severity must be understood to save the life and property to mitigate the natural disaster like an earthquake by proper disaster mitigation plans, especially in the metropolitan cities like Delhi NCR. [ABSTRACT FROM AUTHOR]

CNT nanofluids are getting attention in heat transfer applications due to their very high thermal conductivity in comparison with conventional fluids. For commercial exploitation of CNT nanofluids as heat transfer media, they must have long-term stability. In this study, the two-step method was modified to prepare dynamically stable CNT nanofluids by utilizing commercial grade multiwalled carbon nanotubes and SDBS as a surfactant. The modified technique consists of separation of coarse agglomerates of CNT from the CNT nanofluids by applying centrifugal action after its preparation. The effect of relative centrifugal force was also studied for the very first time on the stable concentration of CNT nanofluids. The stability of CNT nanofluids was analyzed by measurement of their CNT concentration and Zeta potential. Results showed that CNT nanofluids possess good stability and remain stable for more than 15 months. In addition to stability, thermo-physical properties such as thermal conductivity, density, and viscosity of CNT nanofluids were also measured. The results of this study elucidated the effect of RCF on the stable concentration of CNT nanofluids. It is expected that the results obtained in this study may significantly contribute to the proper tailoring of CNT nanofluids, by providing long-term stable CNT nanofluids which are suitable for industrial heat transfer applications. [ABSTRACT FROM AUTHOR]

Plants are continually facing biotic and abiotic stresses, and hence, they need to respond and adapt to survive. Plant response during multiple and combined biotic and abiotic stresses is highly complex and varied than the individual stress. These stresses resulted alteration of plant behavior through regulating the levels of microRNA, heat shock proteins, epigenetic variations. These variations can cause many adverse effects on the growth and development of the plant. Further, in natural conditions, several abiotic stresses causing factors make the plant more susceptible to pathogens infections and vice-versa. A very intricate and multifaceted interactions of various biomolecules are involved in metabolic pathways that can direct towards a cross-tolerance and improvement of plant’s defence system. Systems biology approach plays a significant role in the investigation of these molecular interactions. The valuable information obtained by systems biology will help to develop stress-resistant plant varieties against multiple stresses. Thus, this review aims to decipher various multilevel interactions at the molecular level under combinatorial biotic and abiotic stresses and the role of systems biology to understand these molecular interactions. [ABSTRACT FROM AUTHOR]

In the present work, acceleration response spectra are determined from earthquakes which have occurred in the NE region and the effect of local geology on its shape is studied. One hundred and ninety-five strong ground motion time histories from 45 earthquakes which have occurred in the NE region having a magnitude range of 3.5 ≤ Mw ≤ 6.9 and a distance range of 20-600 kms are used. It is observed that the shape of the normalized acceleration response spectra is influenced by the local site conditions and regional geology. The influence of magnitude and distance on the spectra is also studied. The present study is carried out for three categories of rocks: Pre-Cambrian, Tertiary and Quaternary. It is inferred that the acceleration response spectra in the current Indian code designed for the entire country are applicable for NE region as it is within the spectral limits prescribed in Indian code. The ground motion is amplified at higher frequencies for stations located on hard rock, while for stations located on alluvium sites, it is amplified at lower frequencies. The sites located on hard rock show lowest values of spectral acceleration than the sites located on alluvium sites. The results obtained in the present study are compared with the similar results obtained in the stable continent region like Gujarat. It is found that the dominating period of response spectrum of similar rock types is found to be at higher side for NE region as compared to Gujarat region. This may be attributed towards the tectonic complexity of the NE region than the stable continent region like Gujarat. [ABSTRACT FROM AUTHOR]

Earthquakes are deadliest among all the natural disasters. The areas that have experienced great/large earthquakes in the past may experience big event in future. In this study, we have simulated Kangra earthquake (1905, Mw 7.8) and a hypothetical great earthquake (Mw 8.5) in the north-west Himalaya using Empirical Green's Function (EGF) technique. Recordings of Dharamsala earthquake (1986, Mw 5.4) are used as Green function with a heterogeneous source model and an asperity. It has been observed that the towns of Kangra and Dharamsala can expect ground accelerations in excess of 1 g in case of a Mw 8.5 earthquake and could have experienced an acceleration close to 1 g during 1905 Kangra earthquake. The entire study region can expect acceleration in excess of 100 cm/s in case of Mw 7.8 and 200 cm/s in case of Mw 8.5. The sites located near the rupture initiation point can expect accelerations in excess of 1 g for the magnitudes simulated. For validation, the estimates of the PGA for Mw 7.8 simulation are compared with isoseismal studies carried out in the same region after the Kangra earthquake of 1905 by converting PGA values to intensities. It was found that the results are comparable. The target earthquakes (Mw 7.8 and Mw 8.5) are simulated at depth of 20 km and 30 km to examine the effect of PGA for different depths. The PGA values obtained in the present analysis gave us an idea about the level of accelerations experienced in the area during 1905 Kangra earthquake. Future construction in the area can be regulated, and built environ can be strengthened using PGA values obtained in the present analysis. [ABSTRACT FROM AUTHOR]

In the present study ground motions for a Mw 8.5 scenario earthquake are estimated at 13 sites in Kumaun-Garhwal region using the empirical Green’s function technique. The recordings of 1991 Uttarkashi earthquake of Mw 6.8 at these sites are used as an element earthquake. A heterogeneous source model consisting of two asperities is considered for simulating the ground motions. The entire central seismic gap (CSG) can expect acceleration in excess of 100 cm/s 2 with NW portion in excess of 400 cm/s 2 and SE between 100 and 200 cm/s 2. The central portion can expect peak ground acceleration (PGA) between 200 and 400 cm/s 2. It has been observed from simulation of strong ground motion that sites located near the rupture initiation point can expect accelerations in excess of 1 g. In the present analysis, Bhatwari and Uttarkashi can expect ground accelerations in excess of 1 g. The estimates of the PGA are compared with earlier studies in the same region using different methodologies and it was found that the results are comparable. This has put constrains on the expected PGAs in this region. The obtained PGA values can be used in identifying the vulnerable areas in the central Himalaya, thereby facilitating the planning, design and construction of new structures and strengthening of the existing structures in the region. [ABSTRACT FROM AUTHOR]

The attenuation characteristics based on coda waves of two areas-Jamnagar and Junagarh of Saurashtra, Gujarat (India)-have been investigated in the present study. The frequency dependent relationships have been developed for both the areas using single back scattering model. The broadband waveforms of the vertical components of 33 earthquakes (Mw 1.5-3.5) recorded at six stations of the Jamnagar area, and broadband waveforms of 68 earthquakes (Mw 1.6-5) recorded at five stations of the Junagarh area have been used for the analysis. The estimated relations for the Junagarh area are: Q = (158 ± 5)f (lapse time : 20 s), Q = (170 ± 4.4)f (lapse time : 30 s) and Q = (229 ± 6.6)f (lapse time : 40 s) and for the Jamnagar area are: Q = (178 ± 3)f (lapse time : 20 s), Q = (224 ± 6)f (lapse time : 30 s) and Q = (282 ± 7)f (lapse time : 40 s). These are the first estimates for the areas under consideration. The Junagarh area appears to be more attenuative as compared to the Jamnagar area. The increase in Q values with lapse time found here for both the areas show the depth dependence of Q as longer lapse time windows will sample larger area. The rate of decay of attenuation ( Q) with frequency for the relations obtained here is found to be comparable with those of other regions of the world though the absolute values differ. A comparison of the coda-Q estimated for the Saurashtra region with those of the nearby Kachchh region shows that the Saurashtra region is less heterogeneous. The obtained relations are expected to be useful for the estimation of source parameters of the earthquakes in the Saurashtra region of Gujarat where no such relations were available earlier. These relations are also important for the simulation of earthquake strong ground motions in the region. [ABSTRACT FROM AUTHOR]

The attenuation properties of the crust in the Chamoli region of Himalaya have been examined by estimating the frequency-dependent relationships of quality factors for P waves (Qα) and for S waves (Qβ) in the frequency range 1.5–24 Hz. The extended coda normalization method has been applied on the waveforms of 25 aftershocks of the 1999 Chamoli earthquake (M 6.4) recorded at five stations. The average value of Qα is found to be varied from 68 at 1.5 Hz to 588 at 24 Hz while it varies from 126 at 1.5 Hz to 868 at 24 Hz for Qβ. The estimated frequency-dependent relations for quality factors are Qα = (44 ± 1)f(0.82±.04) and Qβ = (87 ± 3)f(0.71±.03). The rate of increase of Q(f) for P and S waves in the Chamoli region is comparable with the other regions of the world. The ratio Qβ/Qα is greater than one in the region which along with the frequency dependence of quality factors indicates that scattering is an important factor contributing to the attenuation of body waves in the region. A comparison of attenuation relation for S wave estimated here (Qβ = 87f0.71) with that of coda waves (Qc = 30f1.21) obtained by M andal et al. (2001) for the same region shows that Qc > Qβ for higher frequencies (>8 Hz) in the region. This indicates a possible high frequency coda enrichment which suggests that the scattering attenuation significantly influences the attenuation of S waves at frequencies >8 Hz. This observation may be further investigated using multiple scattering models. The attenuation relations for quality factors obtained here may be used for the estimation of source parameters and near-source simulation of earthquake ground motion of the earthquakes, which in turn are required for the assessment of seismic hazard in the region. [ABSTRACT FROM AUTHOR]

Antioxidants can remove damaging reactive oxygen species produced as by-products of desiccation and respiration during late embryogenesis, imbibition of dormant seeds and germination. We have expressed a protein, PER1, encoded by the Balem ( barley aleurone and embryo) transcript previously called B15C, and show it to reduce oxidative damage in vitro. PER1 shares high similarity to a novel group of thiol-requiring antioxidants, named peroxiredoxins, and represents a subgroup with only one conserved cysteine residue (1-Cys). PER1 is the first antioxidant belonging to the 1-Cys subgroup shown to be functionally active, and the first peroxiredoxin of any kind to be functionally described in plants. The steady state level of the transcript, Per1, homologous to a dormancy-related transcript (pBS128) from bromegrass ( Bromus secalinus), increases considerably in imbibed embryos from dormant barley ( Hordeum vulgare L.) grains. Our investigations also indicate that Per1 transcript levels are dormancy-related in the aleurone layer of whole grains. In contrast to most seed-expressed antioxidants Per1 disappears in germinating embryos, and in the mature aleurone the transcript is down-regulated by the germinating embryo or by gibberellic acid (GA). Our data show that the barley seed peroxiredoxin is encoded by a single Per1 gene. Possible roles of the PER1 peroxiredoxin in barley grains during desiccation, dormancy and imbibition are discussed. [ABSTRACT FROM AUTHOR]

Microbial secondary metabolites (SMs) have been identified as an important natural source of drugs for several metabolic and neurological diseases. Along with biomedical applications, SMs are also used in the food and biochemical industries. SMs include natural products such as pigments, alkaloids, toxins, antimicrobials obtained from cultured microorganisms, while other non-cultivable microorganisms have also acted as a rich source of SMs. But, the isolation of SMs from these sources is a very tedious task. Metabolomics provides complete identification and structural information about the entire cellular metabolome under specific conditions using highly sophisticated instrumentation. Further, gene editing techniques such as cloning and gene refactoring, including advanced CRISPR-Cas, can be used for engineering microbes that have the potential to produce natural SMs that were not produced in native microbial strain. The present review describes integrated metabolomics and gene editing approaches for the synthesis of novel microbial SMs and their potential application towards drug discovery and development. [ABSTRACT FROM AUTHOR]