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Thirty-six structurally diverse sesquiterpenoids, including caryolanes (1–12), germacranes (13–16), isodaucane (17), cadinanes (18–22), epicubenols (23, 24), oplopanane (25), pallenanes (26, 27), and eudesmanes (28–36), were isolated from the fermentation broth of Streptomyces fulvorobeus derived from Elephas maximus feces. Pallenane is a kind of rarely reported sesquiterpene with a distinctive C5/C3 bicyclic skeleton and was firstly found from microbial source. The structures of fifteen new compounds (1–4, 13–15, 17, 18, 22, 23, 25–28) were established through detailed spectroscopic data analysis, which included data from experimental and calculated ECD spectra as well as Mosher’s reagent derivative method. Compound 34 exhibited moderate antifungal activity against Cryptococcus neoformans and Cryptococcus gattii with MIC values of 50 μg/mL. It effectively inhibited biofilm formation and destroyed the preformed biofilm, as well as hindered the adhesion of Cryptococcus species. The current work would enrich the chemical diversity of sesquiterpenoid family.

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The computational characteristics of the fast Fourier transform associated with real-time information signals using traditional techniques is deemed the maximal hardware void with peak power consumption, which is an essential task for any researchers while illustrating the designs of architectures in very large-scale integration circuits. The proposed scheme associated with the pipeline reduces the time of processing at the cost of several registers, and to ensure the efficient contribution for reducing the power, the modification over the complex and critical multiplier has been introduced with minimal internal real-time multipliers, which in turn is reconstructed by canonical signed digit multipliers with the adaptation over the technique of resource sharing. The verification of the results of experimentation has been made. It is inferred that the proposed incorporated design is highly efficient regarding area, speed, and power compared to state-of-the-art techniques.

The Qinghai-Tibet Plateau (QTP) is a vital region for global atmospheric circulation and biodiversity. This study aims to evaluate the contents and enrichment status of 25 soil elements, namely Al, As, Ca, Cd, Co, Cr, Cu, K, Mg, Mn, Mo, N, Na, Ni, P, Pb, S, Sc, Si, Sn, Sr, Fe, Ti, V, and Zn, in the plateau region. Specifically, our analysis revealed that As exhibited significant enrichment near fault zones and intrusive rocks, while Ca was mainly enriched due to the dissolution of carbonate rocks. Additionally, Principal Component Analysis and Multiple Linear Regression (PCA-MLR) were used to examine the origins of these elements. The potential ecological risk posed by Cd and Pb was evaluated and found to be negligible. Soil element enrichment in the QTP was mainly influenced by lithology, and high spatial variability was observed in As, Ca, and S, which were mainly affected by geological processes and grazing activities. Six sources of elements in the plateau region were identified, namely geological mixed sources, grazing activities, alkaline granite, ultrabasic rocks, fault zones and intrusive rocks, as well as atmospheric deposition. Among these, geological mixed sources and grazing activities were determined to be the priority contributors. Although grazing activities on the QTP as well as atmospheric deposition at long distances caused the enrichment of elements in the area, the ecological risk was negligible. The outcomes of this work can be used as a theoretical basis for prospective investigation on the stability of high-altitude ecosystems, species diversity, and geochemical background.

Quaternary chalcogenides doped with transition metals are currently being investigated due to their low toxicity and abundance in nature. These systems are especially well suited for thin-film solar cells applications due to their abundance in nature. In this study, we used the microwave-assisted solvothermal method to synthesize p-type quaternary semiconducting nanomaterials Cu₂ZnSnS₄ and Cu₂Zn_0.5Ni_0.5SnS₄ by using one-pot microwave-assisted solvothermal reactions which is treated at 180 – 200 °C (900W power) for 20 min in inside a domestic microwave oven. It was found that a wide range of structural parameters in the synthesized material could be characterized using X-ray diffraction methods, Raman spectral analysis, scanning electron microscopes (FESEM), energy-dispersive spectroscopy (EDS), transmission electron microscope (TEM), and UV–Vis spectrophotometers. It was found that the prepared material exhibited a kesterite crystal structure with crystallite sizes ranging from 20 to 40 nm. FESEM and TEM analysis exposes the morphological features and EDS analysis confirms stoichiometric ratio of the prepared nanomaterials. The optical absorption measurements showed that the nanostructures prepared had band gaps ranging from 1.58 eV to 1.45 eV, according to the optical absorption analysis. In order to finish the thin-film solar cell production process and to further investigate the properties of the CZTS and CZNTS layers, the following additional layers were deposited: CdS with chemical bath deposition; ZnO-Al with RF magnetron deposition; and, finally, Ni-Ag fingers as the front contact. Measurements were made of the thin-film solar cells' efficiency and properties, such as CZTS—3.10% and CZNTS—5.873%, respectively. The prepared materials and properties suggested that these two quaternary chalcogenide systems could be suitable low-cost solar absorber material for thin-film solar cells (TFSC) applications.

Ultrasonic sounding, petrographic image analysis, and mercury intrusion porosimetry was performed on 52 Westerly granite (Rhode Island, USA) specimens exposed to controlled heating from 100 °C to 800 °C. Elastic wave velocities, dynamic elastic moduli, and amplitudes decreased quasilinearly by more than 65% (P-wave), 75% (S-wave), and over 90% (elastic moduli). Damage evaluation by using two crack density parameters proved similar behavior. Direct and indirect evaluation of thermal treatment related microcracks by means of petrographic image analysis and mercury intrusion porosimetry revealed exponential character of porosity evolution, being accelerated above the (alpha -beta) quartz phase transition. Discrepancy between thermal treatment and profoundly non-linear increase in porosity and microcrack density can be satisfactorily explained from direct microscopic observation which revealed formation of crushed/powdered minerals within newly formed microcracks in 650‒800 °C range being related to tension-shearing along grain boundaries of phases with contrasting linear thermal expansion coefficients. This damage phenomenon, resulting in the so-called “clogged” porosity evidently overvalued measured elastic wave velocities. Current results thus underline importance of application of various methods / techniques during examination of changes in rock microfabric from decay processes because none of the methods is capable to cover all important factors alone.

Urmia Lake (UL), one of the most important saline ecosystems in the world, has faced a severe water level drop in the last two decades. In this research, the seasonality of precipitation in the Urmia Lake basin (ULB) was analyzed using the daily precipitation data of 30 rain-gauge stations in the period 1991–2018. The occurrence time of extreme precipitation (OTEP) was determined by using circular statistics. The uniformity of OTEP was examined by Rayleigh test (RT) and Kuiper test (KT). The slope of the trend lines for the OTEP was estimated using the modified Sen’s estimator. Trends in the OTEP were analyzed by the non-parametric Mann–Kendall test. The results indicated no uniformity in the OTEP at 0.1, 0.05, and 0.01 levels in the basin. Seasonal events throughout the year were divided into two separate seasons denoted by S1 for late winter and early spring and S2 for autumn. The results showed that the mean seasonality increased from 0.3 to 0.82 (for S1) and 0.9 for S2. The comparison of seasonal strength in the west and east parts of ULB revealed that these two parts of ULB had the same seasonality strength (SS) in the S1. However, the seasonality of the western part of the lake was stronger than the eastern part in S2. Trends in OTEP showed that about 60% of the stations witnessed upward trends in S1. This was about 27% in S2. The findings of this analysis can provide useful information about the changes in the OTEP and its hydrological impact on the studied basin. This information is helpful in the scientific management of water resources in the Urmia Lake basin.

α-Fe₂O₃, (Fe₇₀Co₃₀)₂O₃, (Fe₇₀La₃₀)₂O₃, (Fe₇₀Co₂₀La₁₀)₂O₃, and (Fe₇₀La₂₀Co₁₀)₂O₃ thin films were synthesized by the spray pyrolysis procedure on glass substrates. The effect of cobalt and lanthanum doping and co-doping on the structural, microstructural, magnetic, and optical properties was investigated using X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), scanning electron microscopy (SEM), vibrating sample magnetometry (VSM), and UV-visible spectroscopy. The XRD analysis revealed the formation of the hematite-type structure for all samples with slight variations in the lattice parameters in the range of a = 5.0212−5.0358 Å and c = 13.7203−13.7416 Å. The crystallite size decreases to 40–58 nm with La³⁺ and Co²⁺ incorporation into the α-Fe₂O₃ crystal structure. Co and La doping and co-doping influence the surface morphology of the films. FTIR analysis confirmed the retention of Fe–O and O–Fe–O vibrations of the hematite matrix. Room temperature hysteresis loops revealed a paramagnetic behavior for the La-doped Fe₂O₃ and a ferromagnetic state with enhanced saturation magnetization for Co-doped and (La, Co) co-doped films. Optical transmittance spectra indicated high transparency, increasing the energy bandgap from 2.22 eV to 2.43 eV. These results highlight the potential of La and Co co-doped hematite thin films for optoelectronic and spintronic applications.