Interspecific competition and their impacts on the growth of macrophytes and pollutants removal within constructed wetland microcosms treating domestic wastewater.

Eight free water surface constructed wetland microcosm (CWM) units are designed with single as well as mixed planting of Pistia stratiotes, Phragmites karka, and Typha latifolia with control to assess their competitive value (CV), relative growth rates (RGR), and pollutants removal efficiency. Further, the total dry biomass production and other growth parameters such as number of macrophytes, above-ground biomass, below-ground biomass, and root length were also measured to understand the dominant characteristics of the macrophytes. The CWM units with species mixture out-performed species monocultures. Removal of BOD, TP, SRP, NH4+-N, NO3--N, and NO2--N by mixed planting of P. stratiotes and P. karka was higher at most of the time. Typha latifolia was the superior competitor against both P. stratiotes and P. karka due to its aggressive characteristics that inhibits the growth of neighboring macrophytes. However, P. karka was the superior competitor against P. stratiotes. The RGR of T. latifolia in all experimental units was almost two times more than that of P. karka. Novelty Statement The CWM units with species mixture out-performed species monocultures. CWMs with more than one macrophytic species are less vulnerable to seasonal fluctuations and more effective in contaminants removal as compared to single macrophyte wetlands. Removal of BOD, TP, SRP, NH4+-N, NO3--N, and NO2--N by mixed planting of P. stratiotes and P. karka was higher at most of the time. The CWMs with P. stratiotes and P. karka are superior choice due to their higher wastewater nutrients removal capacity. The application of these three macrophytes in mixed cultures in free water surface constructed wetland is rare. The results are useful in designing large-scale multi-species wetlands which are less susceptible to seasonal variation and more effective in pollutants removal than single-species wetlands.

Constructed wetlands for the removal of pharmaceuticals and personal care products (PPCPs) from wastewater: origin, impacts, treatment methods, and SWOT analysis.

The continuous exposure to pharmaceuticals and personal care products can lead to a series of individual antagonistic and synergistic effects and long-lasting toxicity to humans and aquatic lives. This may also lead to developing antibiotic resistance, teratogenic, carcinogenic, and endocrine-disrupting effects. However, several PPCPs are also considered biologically active for non-target aquatic organisms, such as mosquito fish, goldfish, and the algae Pseudokirchneriella subcapitata. Various physicochemical methods such as ozonation, photolysis, and membrane separation are recognized for the effective removal of PPCPs. However, the high operation and maintenance costs and associated ecological impacts have limited their further use. Constructed wetlands are considered eco-friendly and sustainable for the removal of pharmaceuticals and personal care products together with antibiotic resistance genes. Several mechanisms such as sorption, biodegradation, oxidation, photodegradation, volatilization, and hydrolysis are occurring during the phytoremediation of PPCPs. During these processes, more than 50% of PPCPs can be eliminated through constructed wetlands. They also offer several additional benefits as obtained macrophytic biomass may be used as raw material in pulp and paper industries and a source for second-generation biofuel production. In this study, we have discussed the origin and impacts of PPCPs together with their treatment methods. We have also investigated the strengths, weaknesses, opportunities, and threats associated with constructed wetlands during the treatment of wastewater laden with pharmaceutical and personal care products.

Rice seed (IR64) priming with potassium humate for improvement of seed germination, seedling growth and antioxidant defense system under arsenic stress.

The intolerable levels of arsenic (As) in groundwater and its application in rice cultivation are continuously affecting the rice production in Ganga-Meghna-Brahmaputra (GMB) plain. The reduced germination and plant growth rates under excessive As stress ultimately lead to lower yield. To mitigate this concerning issue, the present study was carried out to evaluate the potential of K-humate priming on seed germination and plant growth under As stress. Seeds were primed with 100 mg/l K-humate for 12 h prior to germination. The germination percentages in unprimed seeds were 65 ±â€¯5.0% and 58.3 ±â€¯7.6% under stress level of 50 µM AsV and 50 µM AsIII, respectively. However, germination percentage in K-humate primed seeds were 75 ±â€¯5.0% and 68.3 ±â€¯2.9% under AsV and AsIII stress, respectively. The vigour index I (VG I) and vigour index II (VG II) recorded on 12 DAS (days after seeding) were also increased by 1.47 and 1.51 fold, respectively with K-humate supplementation under As stress. Detrimental effects of AsIII on seed germination, seedling growth and other physiological parameters were more suppressive than AsV. Application of K-humate not only improved seed germination, seedling growth and nutrient uptake but also decreased the oxidative stress markers and antioxidant activities by minimizing As uptake and translocation in the seedlings.

Synergy of hybridization of bauhinia vahlii and kenaf fiber on mechanical and sliding wear properties of epoxy composites: A Grey Taguchi Optimization Study.

The present research work aims to develop Bauhinia vahlii fibre epoxy composites with incorporation of different weight percentage (wt%) of kenaf fiber as secondary reinforcement to elevate the mechanical and wear properties of prepared composites (through hand layup method). Higher value of mechanical properties like tensile strength-114.85 MPa, flexural strength- 64.64 MPa, and hardness- 57.2 Hv are achieved for bauhina vahlii-epoxy composites. In case of hybrid composites, tensile strength-161.92 MPa; flexural strength- 93.28 MPa; and hardness- 76.0Hv for bauhinia vahlii/kenaf-epoxy composites at 10 wt% of fiber reinforcement. The design of experiment is developed by Taguchi L9 orthogonal array to optimize the experimental run with three control factors; sliding velocity, fiber wt%, and normal load. In order to assess the multiple responses, the fabricated composite is analysed by Grey-Taguchi method with optimal factor setting to improve the output responses i.e. specific wear rate, tensile strength, flexural strength, and hardness. The optimal parameters which highly affect the properties of composites are sliding velocity (2.5 m/s), fiber wt% (10 wt %), and normal load (15 N). In wear mechanism analysis of composites by scanning electron microscopy (SEM), it is demonstrated that the synergy of hybridization of bauhinia vahlii and kenaf fiber improved the mechanical and wear properties of composites.

Macroeconomic effects of uncertainty: a Google trends-based analysis for India.

This study proposes a new high-frequency indicator to measure economic policy uncertainty in the context of India, a large emerging market economy. Based on internet search intensity data, the proposed index tends to peak around domestic and global events associated with uncertainty that may prompt economic agents to alter their decisions to spend, save, invest and hire. Using an external instrument with structural vector autoregression (SVAR-IV) framework, we provide fresh evidence on the causal impact of uncertainty on the Indian macroeconomy. We show that surprise increases in uncertainty lead to a fall in output growth and an increase in inflation. This effect is found to be mainly driven by a fall in private investments vis-à-vis consumption indicating a dominant supply-side impact of uncertainty. Lastly, taking the case of output growth, we show that adding our uncertainty index to standard forecasting models leads to better forecasting accuracy compared to other alternate indicators of macroeconomic uncertainty.

Impact of RBI's monetary policy announcements on government bond yields: evidence from the pandemic.

We investigate how the bond market responded to the Reserve Bank of India's (RBI) monetary policy actions undertaken since the start of the pandemic. Our approach involves combining a narrative analysis of the media coverage together with an event-study framework around RBI's monetary policy announcements. We find that the RBI's actions early in the pandemic were helpful in providing an expansionary impulse to the bond market. Specifically, long-term bond interest rates would have been meaningfully higher in the early months of the pandemic if not for the actions undertaken by the RBI. These actions involved unconventional policies providing liquidity support and asset purchases. We find that some of the unconventional monetary policy actions had a substantial signaling channel component where the market perceived the announcement of an unconventional monetary policy action as representing a lower future path for the short-term policy rate. We also find that the RBI's forward guidance was more effective in the pandemic than it had been in the couple of years preceding the pandemic.

Wastewater generation and treatment by various eco-friendly technologies: Possible health hazards and further reuse for environmental safety.

The discharge of untreated wastewater as a result of various developmental activities such as urbanization, industrialization and changes in lifestyle poses great threats to aquatic ecosystems as well as humans. Currently, ∼380 billion m3 (380 trillion liters) of wastewater is generated globally every year. Around 70% of freshwater withdrawals are used for agricultural production throughout the world. The wastewater generated through agricultural run-off further pollutes freshwater resources. However, only 24% of the total wastewater generated from households and industries is treated before its disposal in rivers or reused in agriculture. The most problematic contaminants associated with ecological toxicity are heavy metals such as Cd, Cr, Cu, Ni, Zn, Fe, Pb, Hg, As and Mn. One of the most important issues linked with wastewater generation is the residual presence of pathogenic microorganisms which pose potential health hazards to consumers when they enter into the food chain. It is estimated that in India almost USD 600 million (48.60 billion INR) is spent per year to tackle waterborne diseases (WBD). In light of this, immediate action is needed to effectively treat wastewater and develop safer reuse prospects. Various wastewater treatment technologies have been established and they work well to provide an alternative water source to meet the growing demand. The main concern towards treating wastewater is to eliminate inorganic and organic substances and lower the nutrient concentration, total solids, and microbial pathogens to prevent freshwater pollution and health risks.

Impact of family-centred postnatal training on maternal and neonatal health and care practices in district hospitals in two states in India: a pre-post study.

BACKGROUND AND OBJECTIVES: The Care Companion Program (CCP) is an in-hospital multitopic skill-based training programme provided to families to improve postdischarge maternal and neonatal health. The states of Punjab and Karnataka in India piloted the programme in 12 district hospitals in July 2017, and no study to date has evaluated its impact. METHODS: We compared telephonically self-reported maternal and neonatal care practices and health outcomes before and after the launch of the CCP programme in 11 facilities. Families in the preintervention group delivered between May to June 2017 (N=1474) while those in the intervention group delivered between August and October 2017 (N=3510). Programme effects were expressed as adjusted risk ratios obtained from logistic regression models. RESULTS: At 2-week postdelivery, the practice of dry cord care improved by 4% (RR=1.04, 95% CI 1.02 to 1.06) and skin-to-skin care by 78% (RR=1.78, 95% CI 1.37 to 2.27) in the postintervention group as compared with preintervention group. Furthermore, newborn complications reduced by 16% (RR=0.84, 95% CI 0.76 to 0.91), mother complications by 12% (RR=0.88, 95% CI 0.79 to 0.97) and newborn readmissions by 56% (RR=0.44, 95% CI 0.31 to 0.61). Outpatient visits increased by 27% (RR=1.27, 95% CI 1.10 to 1.46). However, the practice of exclusive breastfeeding, unrestricted maternal diet, hand-hygiene and being instructed on warning signs were not statistically different. CONCLUSION: Postnatal care should incorporate predischarge training of families. Our findings demonstrate that it is possible to improve maternal and neonatal care practices and outcomes through a family-centered programme integrated into public health facilities in low and middle-income countries.

Hydrograph apportionment of the Chandra River draining from a semi-arid region of the Upper Indus Basin, western Himalaya.

Melting of snow and glaciers from the high-altitude Himalayan region is a significant water source to the major Himalayan rivers, especially in the upper Indus Basin (UIB), which contributes up to 70% of river discharge. Considering Indus Basin as a largest irrigation system dependent on snow and glacier melt runoff, it is imperative to study the rivers' current status and water budget. In this study we have performed a tracer-based hydrograph separation to quantify the contribution of seasonal snow, glacier melt, and groundwater to the Chandra River draining from a semi-arid region of the upper Indus basin, western Himalaya. Our study revealed a negligible control of summer (May-September 2017) precipitation and significant control of summer air temperature (May-September 2017) and winter precipitation over the Chandra River discharge, with 1 °C rise in air temperature leading to 22 m3s-1 (15% of mean) increase in the river discharge (R2 = 0.85; n = 541; p < 0.001). The hydrograph separation of the Chandra River suggests groundwater (38.3 ± 5.6%; 96.8 m3s-1) as a significant source to the river runoff, followed by a direct contribution from glacier melt (30.9 ± 9%; 88.2 m3s-1) and seasonal snowmelt (30.6 ± 5.7%; 84.2 m3s-1), respectively, with negligible contribution from rainfall. Although groundwater is a significant contributor to the river runoff, the infiltration of seasonal snowmelt (54%) and glacier melt (46%) mostly contributed to the groundwater recharge. Present study establishes a linkage between seasonal snowmelt, glacier melt, groundwater, and the river runoff and would be useful to better model and predicts the future changes in the water resources of the upper Indus Basin.

Variation in extracellular enzyme activities and their influence on the performance of surface-flow constructed wetland microcosms (CWMs).

Eight constructed wetland microcosm (CWM) units have been designed using three macrophytes for domestic wastewater treatment. The main aim of this study is to evaluate enzyme activities with respect to time and soil depth and their correlation with removal efficiency of pollutants within different CWM units. The findings of this study show that the activity of enzymes and pollutants removal efficiency vary to a great extent on the soil depth, time of the sampling and type of pollutants. The correlation between removal of soluble reactive phosphorus and total phosphorus was significant with phosphatase activity in most of the CWM units. Activity of urease and NH4+-N removal was positively correlated with significant positive correlation in CWM units planted with Phragmites karka, and Pistia stratiotes (Ph + Pi) and Typha latifolia, Phragmites karka and Pistia stratiotes (T + Ph + Pi). Urease activity was found to be both positively and negatively correlated with respect to removal of NO3--N and NO2--N in different CWM units. Dehydrogenase activity showed negative correlation with respect to biological oxygen demand (BOD) removal except in CWM units with Ph + Pi and T + Ph + Pi. Similarly, a moderate positive and negative correlation exists between fluorescein diacetate hydrolysis and BOD removal. Removal of BOD and microbial biomass carbon (MBC) was negatively correlated with each other in most of the CWM units. With respect to vertical variation, the top layer of CWM units expressed significantly higher activity of extracellular enzymes and were significantly different from the deeper layer. CWM units exhibited significant variations in enzyme activity with respect to time.

Structural and functional characterization of M. tuberculosis sedoheptulose- 7-phosphate isomerase, a critical enzyme involved in lipopolysaccharide biosynthetic pathway.

M. tuberculosis GmhA enzyme catalyzes the isomerization of D-sedoheptulose 7-phosphate into D-glycero-D-α-manno-heptose-7-phosphate in GDP-D-glycero-α-D-manno-heptose biosynthetic pathway. The D-glycero-α-D-manno-heptose is a major constituent of lipopolysaccharide and contributes to virulence and antibiotic resistance to mycobacteria. In current study, we have performed the structural and biochemical analysis of M. tuberculosis GmhA, the first enzyme involved in D-sedoheptulose 7-phosphate isomerization in GDP-D-α-D-heptose biosynthetic pathway. The MtbGmhA enzyme exits as tetramer and small angle X-ray scattering analysis also yielded tetrameric envelope in solution. The MtbGmhA enzyme binds to D-sedoheptulose 7-phosphate with Km ~ 0.31 ± 0.06 mM-1 and coverts it to D-glycero-D-α-manno-heptose-7-phosphate with catalytic efficiency (kcat/Km) ~ 1.45 mM-1 s-1. The residues involved in D-sedoheptulose 7-phosphate and Zn2+ binding were identified using modeled MtbGmhA + D-sedoheptulose 7-phosphate + Zn2+ structure. To understand the role in catalysis, six site directed mutants of MtbGmhA were generated, which showed significant decrease in catalytic activity. The circular dichroism analysis showed ~ 46% α-helix, ~ 19% ß-sheet and ~ 35% random coil structures of MtbGmhA enzyme and melting temperature ~ 53.5 °C. Small angle X-ray scattering analysis showed the tetrameric envelope, which fitted well with modeled MtbGmhA tetramer in closed conformation. The MtbGmhA dynamics involved in D-sedoheptulose 7-phosphate and Zn2+ binding was identified using dynamics simulation and showed enhanced stability in presence of these ligands. Our biochemical data and structural knowledge have provided insight into mechanism of action of MtbGmhA enzyme, which can be targeted for novel antibiotics development against M. tuberculosis.

Modeling based experimental investigation on polymerization shrinkage and micro-hardness of nano alumina filled resin based dental material.

This paper investigates the effect of %wt composition of BisGMA/TEGDMA, stirring time, bench time, curing time and filler loading on polymerization shrinkage and micro-hardness of resin based dental composites. The investigation was carried out in two stages. In first stage, samples were prepared with different %wt composition of BisGMA/TEGDMA, stirring time, bench time, and curing time to access the effect of different input parameters for minimum polymerization shrinkage and maximum micro-hardness using Taguchi methodology. Selecting optimum values of input factors from first stage, second stage optimization was performed to investigate the effects of different filler loading on different %wt composition of BisGMA/TEGDMA using full factorial design. Prediction model was developed using Design Expert software and analysis of effect of input parameters on output responses were carried out using 3D surface plots. ANOVA were performed to check the significance of prediction model. In first stage, optimum stirring time, bench time and curing time were found to be 4 h, 50 min and 30 s, respectively. In second stage, optimum polymerization shrinkage and micro-hardness of 3.54% and 310 Hv were predicted at 22.89% of TEGDMA content and 20% filler loading. Taguchi methodology and full factorial design were successfully implemented to access the effect of multi-input parameters on responses for resin based dental composites.

Resin based restorative dental materials: characteristics and future perspectives.

This review article compiles the characteristics of resin based dental composites and an effort is made to point out their future perspectives. Recent research studies along with few earlier articles were studied to compile the synthesis schemes of commonly used monomers, their characteristics in terms of their physical, mechanical and polymerization process with selectivity towards the input parameters of polymerization process. This review covers surface modification processes of various filler particles using silanes, wear behaviour, antimicrobial behaviour along with its testing procedures to develop the fundamental knowledge of various characteristics of resin based composites. In the end of this review, possible areas of further interests are pointed out on the basis of literature review on resin based dental materials.

Low-resolution SAXS and structural dynamics analysis on M. tuberculosis GmhB enzyme involved in GDP-heptose biosynthetic pathway.

The M. tuberculosis GmhB protein converts the d-glycero-α-d-manno-heptose 1,7-bisphosphate (GMB) intermediate into d-glycero-α-d-manno-heptose 1-phosphate by removing the phosphate group at the C-7 position. To understand the structure and substrate binding mechanism, the MtbGmhB was purified which elutes as monomer on gel filtration column. The small angle x-ray scattering analysis shows that MtbGmhB forms fully folded monomer with shape profile similar to its modeled structure. The circular dichroism analysis shows 38% α-helix, 15% ß-sheets and 47% random coil structures in MtbGmhB, similar to haloalkanoic acid dehalogenase (HAD) phosphohydrolase enzymes. The modeled MtbGmhB structure shows the catalytic site, which forms a concave, semicircular surface using the three loops around GMB substrate binding site. Dynamic simulation analysis on (i) Apo (ii) GMB bound (iii) GMB + Mg2+ bound (iv) Zn2+ +GMB + Mg2+ bound MtbGmhB structures show that Zn2+ as well as Mg2+ ions stabilize the loop conformation and trigger the changes in GMB substrate binding to active site of MtbGmhB. Upon demetallization, the large conformational changes occurred in ions binding loops, and leads to difference in GMB substrate binding to MtbGmhB. Our study provides information about structure and substrate binding of MtbGmhB, which may contribute in therapeutic development against M. tuberculosis.