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The high thermoelectric performance of dopant-free, low-cost and eco-friendly p-type Zn1−xSb (x = 0, 0.01, 0.03, and 0.06) is demonstrated by synergistically optimizing its electrical and thermal properties via Zn-vacancy engineering. Upon increasing Zn-vacancies in ZnSb, the bandgap is observed to reduce due to the formation of the impurity states above the valence band, which is theoretically validated using density functional theory (DFT). Remarkably, Zn vacancy-driven point defects significantly influence the hole concentration within the Zn1−xSb samples. At 300 K, the hole concentration (nH) is boosted from 3.6 × 1018 cm−3 (in ZnSb) to 3.4 × 1019 cm−3 for the Zn0.94Sb sample, culminating in a marked enhancement in electrical conductivity (σ) from 1.80 × 104 S m−1 to 7.57 × 104 S m−1 for Zn0.94Sb. Equally noteworthy is the substantial decrease in thermal conductivity (κ) observed in the Zn0.94Sb sample at 673 K, plunging from 2.29 W m−1 K−1 (in ZnSb) to 1.41 W m−1 K−1. This decline in thermal conductivity is attributed to the effective phonon scattering arising from Zn-vacancy-assisted point defects, combined with the efficient coupling of optical and acoustic phonons and the characteristic low group velocity, evidenced by the theoretically calculated phonon dispersion curve. Overall, the high thermoelectric figure of merit, zT of ∼0.8 at 673 K, is achieved for the sample with a 6 mol% Zn deficiency. Furthermore, a maximum theoretical conversion efficiency of ∼7% is predicted at a temperature gradient of 625 K, showing high potential for use in practical devices for mid-temperature applications, and the present work features the effect of a reliable dopant-free approach in improving the overall zT of eco-friendly and low-cost ZnSb. [ABSTRACT FROM AUTHOR]

A total of 87 FPs have been isolated from tomato (Lycopersicon esculentum) rhizosphere and evaluated by dual plate assay method for the antimicrobial activity of Ralstonia solanacearum. Of which, 30 FPs showed antagonistic activity against R. solanacearum with the zone of inhibitions (ZOI) ranging from 19 mm to 28 mm. Similarly, antagonistic FPs significantly controlled various fungal phytopathogens such as Rhizoctonia solani (6.3 mm−20 mm), Macrophomina phaseolina (8.7 mm−19.3 mm), Fusarium oxysporum (7.3 mm−30.7 mm), and Sclerotium rolfsii (5.3 mm−21 mm). The cell-free culture filtrate of Pseudomonas sp VSMKU3054 significantly suppressed the fungal pathogens and increased the root and shoot length of the tomato seedlings compared to the control. Furthermore, the antagonistic FPs effectively produced lytic enzymes and antimicrobial traits such as amylase (6), protease (30), cellulase (28), pectinase (12), chitinase (22), gelatinase (27), siderophore (28), hydrogen cyanide (25), phosphate solubilization (30), and Indole acetic acid (IAA) (23). Genetic diversity of FPs was assessed by BOX-PCR with specific primers revealed that two distinct clusters were observed, whereas, RFLP analyses were showed that 5 to 16 bands ranged from 75 bp to 1.2 bp with two major clusters using restriction enzyme HaeIII. The antibiotic encoding genes were detected from FPs, of which 10 FPs were positive for 2,4-diacetylphloroglucinol (DAPG), 9 FPs were positive for pyoleuterin (PLT), 10 FPs were positive for hydrogen cyanide (HCN) and none of them obtained pyrrolnitrin (PRN) with respective primers. Based on the superior antagonistic isolates against R. solanacearum and phytofungal pathogens and other antimicrobial traits, the isolate VSMKU3054 was selected for further studies. Based on the morphological, physiological and 98% of 16 s rDNA sequence similarity, the selected isolate VSMKU3054 was identified as Pseudomonas fluorescens. Further, the potential isolate P. fluorescens VSMKU3054 and cell free culture filtrate remarkably enhance tomato seedling growth such as root and shoot length, fresh and dry weight and vigor index compared to control. This study indicated that rhizospheric isolates of FPs have more potential for plant growth promotion and plant protection from plant pathogenic microbes.

Microbial bio-products are becoming an appealing and viable alternative to chemical pesticides for effective management of crop diseases. These bio-products are known to have potential to minimize agrochemical applications without losing crop yield and also restore soil fertility and productivity. In this study, the inhibitory efficacy of 2,4-diacetylphloroglucinol (DAPG) produced by Pseudomonas fluorescens VSMKU3054 against Ralstonia solanacearum was assessed. Biochemical and functional characterization study revealed that P. fluorescens produced hydrogen cyanide (HCN), siderophore, indole acetic acid (IAA) and hydrolytic enzymes such as amylase, protease, cellulase and chitinase, and had the ability to solubilize phosphate. The presence of the key antimicrobial encoding gene in the biosynthesis of 2,4-diacetylphloroglucinol (DAPG) was identified by PCR. The maximum growth and antimicrobial activity of P. fluorescens was observed in king’s B medium at pH 7, 37 °C and 36 h of growth. Glucose and tryptone were found to be the most suitable carbon and nitrogen sources, respectively. DAPG was separated by silica column chromatography and identified by various methods such as UV-Vis, FT-IR, GC-MS and NMR spectroscopy. When R. solanacearum cells were exposed to DAPG at 90 µg/mL, the cell viability was decreased, reactive oxygen species (ROS) were increased and chromosomal DNA was damaged. Application of P. fluorescens and DAPG significantly reduced the bacterial wilt incidence. In addition, P. fluorescens was also found effective in promoting the growth of tomato seedlings. It is concluded that the indigenous isolate P. fluorescens VSMKU3054 could be used as a suitable biocontrol agent against bacterial wilt disease of tomato.

Background and aim: Cricket is the most commonly played and followed sport in India and demands a high level of performance from the fast bowler. Large ground reaction forces generated at front foot contact put fast bowlers at high risk of lower limb and lumbar spine injury. Precise dynamic coordination of lower body segments is needed to absorb these forces and transfer the energy via the core to the upper limb to propel the ball at faster speeds. Thus, knowledge of lower quadrant strength, especially dynamic knee strength, can be useful for injury prevention and better performance in fast bowlers. There is a lack of literature on this subject in Indian fast bowlers despite the popularity of the sport. This study aims to evaluate isokinetic knee strength and determine the relevant asymmetries and strength imbalances in relation to injury risk in cricket fast bowlers. Methods: A total of 42 male Indian state-level fast bowlers underwent isokinetic knee strength testing. Peak torques (PT) normalized to body weight (BW) were obtained for quadriceps concentric (Qconc), quadriceps eccentric (Qecc), hamstring concentric (Hconc), and hamstring eccentric (Hecc). Bilateral strength asymmetries (BSA) and dynamic control ratio (DCR) (hamstring DCR (H-DCR) = Hecc/Qconc and quadriceps DCR (Q-DCR) = Qecc/Hconc) were evaluated. Descriptive statistical analysis of data was done. Results: Around 67% of bowlers had significant Qecc strength asymmetry. In addition, 40% had poor hamstrings DCR and 19% had poor Q-DCR on the front limb. Conclusion: A significant proportion of fast bowlers have unfavorable strength asymmetry and DCR and could be at risk of injury. Improving dynamic knee strength through plyometric training could help optimize performance and reduce injury risk. Clinical significance: This study highlights key areas of possible injury risk that can be targeted with strength and conditioning to prevent lower limb and lumbar spine injuries in fast bowlers. [ABSTRACT FROM AUTHOR]