•A review update on recent trends on endophyte mediated podophyllotoxin production.•Isolation and extraction of podophyllotoxin.•Podophyllum and allied plants associated with endophytes producing ...podophyllotoxin.•Yield, bottleneck and future prospects of endophyte mediated podophyllotoxin production.
Investigation on the secondary metabolites of endophytic organisms colonized within plant body is now giving emphasis on the medicinal properties of those products aiming to the finding of new drug molecules. Podophyllotoxin is a non-alkaloid lignan of plant origin found in some species of Podophyllum and several other genera such as Sinopodophyllum, Juniperus, Dysosma, Diphylleia, Linum, Lithospermum and so on. A few endophytic fungi which produce podophyllotoxin as secondary-metabolite are explored and reported in some available literatures. Isolation of specific endophytic fungal strains and their metabolite extraction can be done by using standard methods. Further research for the discovery of many other podophyllotoxin producing fungal endophytes and use of industrial fermentation technology may help in mass production. Survey of podophyllotoxin producing bacterial endophytic strains is also a prerequisite regarding commercial enrichment. It will certainly limit the overuse of the respective medicinal plant resources. Therefore, proper care must be taken and necessary policy may be formed by the appropriate authority to conserve these commercially valuable botanicals associated with endophytes. Informative knowledge about the wider distribution of endophytic microbes depending on the internal and external condition of the plant tissue may help to comprehend the role of those organisms in the production of bioactive metabolites.
This paper introduces a low-complexity algorithm for the extraction of the fiducial points from the electrocardiogram (ECG). The application area we consider is that of remote cardiovascular ...monitoring, where continuous sensing and processing takes place in low-power, computationally constrained devices, thus the power consumption and complexity of the processing algorithms should remain at a minimum level. Under this context, we choose to employ the discrete wavelet transform (DWT) with the Haar function being the mother wavelet, as our principal analysis method. From the modulus-maxima analysis on the DWT coefficients, an approximation of the ECG fiducial points is extracted. These initial findings are complimented with a refinement stage, based on the time-domain morphological properties of the ECG, which alleviates the decreased temporal resolution of the DWT. The resulting algorithm is a hybrid scheme of time- and frequency-domain signal processing. Feature extraction results from 27 ECG signals from QTDB were tested against manual annotations and used to compare our approach against the state-of-the art ECG delineators. In addition, 450 signals from the 15-lead PTBDB are used to evaluate the obtained performance against the CSE tolerance limits. Our findings indicate that all but one CSE limits are satisfied. This level of performance combined with a complexity analysis, where the upper bound of the proposed algorithm, in terms of arithmetic operations, is calculated as 2.423 N +214 additions and 1.093 N +12 multiplications for N ≤ 861 or 2.553 N +102 additions and 1.093 N +10 multiplications for N > 861 ( N being the number of input samples), reveals that the proposed method achieves an ideal tradeoff between computational complexity and performance, a key requirement in remote cardiovascular disease monitoring systems.
Pattern recognition receptors (PRRs) coordinate the innate immune response and have a significant role in the development of multiple sclerosis (MS). Accumulating evidence has identified both ...pathogenic and protective functions of PRR signaling in MS and its animal model, experimental autoimmune encephalomyelitis (EAE). Additionally, evidence for PRR signaling in non-immune cells and PRR responses to host-derived endogenous ligands has also revealed new pathways controlling the development of CNS autoimmunity. Many PRRs remain uncharacterized in MS and EAE, and understanding the distinct triggers and functions of PRR signaling in CNS autoimmunity requires further investigation. In this brief review, we discuss the diverse pathogenic and protective functions of PRRs in MS and EAE, and highlight major avenues for future research.
To meet the unprecedented requirement of diagnostic testing for SARS-CoV-2, a large number of diagnostic kits were authorized by concerned authorities for diagnostic use within a short period of time ...during the initial phases of the ongoing pandemic. We undertook this study to evaluate the inter-test agreement and other key operational features of 5 such commercial kits that have been extensively used in India for routine diagnostic testing for COVID-19. The five commercial kits were evaluated, using a panel of positive and negative respiratory samples, considering the kit provided by National Institute of Virology, Indian Council of Medical Research (2019-nCoV Kit) as the reference. The positive panel comprised of individuals who fulfilled the 3 criteria of being clinically symptomatic, having history of contact with diagnosed cases and testing positive in the reference kit. The negative panel included both healthy and disease controls, the latter being drawn from individuals diagnosed with other respiratory viral infections. The same protocol of sample collection, same RNA extraction kit and same RT-PCR instrument were used for all the kits. Clinical samples were collected from a panel of 92 cases and 60 control patients, who fulfilled our inclusion criteria. The control group included equal number of healthy individuals and patients infected with other respiratory viruses (n = 30, in each group). We observed varying sensitivity and specificity among the evaluated kits, with LabGun COVID-19 RT-PCR kit showing the highest sensitivity and specificity (94% and 100% respectively), followed by TaqPath COVID-19 Combo and Allplex 2019-nCoV assays. The extent of inter-test agreement was not associated with viral loads of the samples. Poor correlation was observed between Ct values of the same genes amplified using different kits. Our findings reveal the presence of wide heterogeneity and sub-optimal inter-test agreement in the diagnostic performance of the evaluated kits and hint at the need of adopting stringent standards for fulfilling the quality assurance requirements of the COVID-19 diagnostic process.
Recent reports challenge the widely accepted idea that drought may offer protection against ozone (O 3 ) damage in plants. However, little is known about the impact of drought on the magnitude of O 3 ...tolerance in winter wheat species. Two winter wheat species with contrasting sensitivity to O 3 (O 3 tolerant, primitive wheat, T. turgidum ssp. durum; O 3 sensitive, modern wheat, T. aestivum L. cv. Xiaoyan 22) were exposed to O 3 (83ppb O 3 , 7h d -1 ) and/or drought (42% soil water capacity) from flowering to grain maturity to assess drought-induced modulation of O 3 tolerance. Plant responses to stress treatments were assessed by determining in vivo biochemical parameters, gas exchange, chlorophyll a fluorescence, and grain yield. The primitive wheat demonstrated higher O 3 tolerance than the modern species, with the latter exhibiting higher drought tolerance than the former. This suggested that there was no cross-tolerance of the two stresses when applied separately in these species/cultivars of winter wheat. The primitive wheat lost O 3 tolerance, while the modern species showed improved tolerance to O 3 under combined drought and O 3 exposure. This indicated the existence of differential behaviour of the two wheat species between a single stress and the combination of the two stresses. The observed O 3 tolerance in the two wheat species was related to their magnitude of drought tolerance under a combination of drought and O 3 exposure. The results clearly demonstrate that O 3 tolerance of a drought-sensitive winter wheat species can be completely lost under combined drought and O 3 exposure.
Phosphorus (P) fertilizers are produced from high-grade rock phosphates (HGRPs). The reserve of HGRP is finite and non-renewable. We are rapidly shrinking this reserve, by producing P fertilizers. ...This fact establishes the need of utilizing low-grade rock phosphates (LGRPs) for growing crops. In this experiment, LGRP was treated with 0.5
M
oxalic acid solution. The oxalic-acid-treated LGRP was used to supplement chemical P fertilizer in incubation as well as pot experiments in Alfisol. During incubation experiment, oxalic-acid-treated LGRP treatment (T
3
) significantly increased soil available P as compared to control (T
1
) and untreated LGRP (T
2
) treatments. Pot study revealed that under DAP+ oxalic-acid-treated LGRP treatment (T
4
), oxalic-acid-treated LGRP (@60 mg P
2
O
5
kg
-1
) supplemented 50% DAP without hampering wheat yield and P uptake, at the same time maintained significantly higher total P, inorganic P, organic-P, Ca-P, saloid P and statistically at par available P, dehydrogenase, acid and alkaline phosphatase activities as compared to DAP treatment (T
3
) at all the growth stages of wheat. So, it can be inferred that 0.5
M
oxalic acid solution treatment can be useful to utilize LGRP as supplemental P source to grow wheat. Oxalic-acid-treated LGRP (@60 mg P
2
O
5
kg
-1
) can successfully supplement 50% of the chemical P fertilizer for growing wheat. It also improves soil P fertility and sustains dehydrogenase, acid phosphatase and alkaline phosphatase activities in Alfisol.
•Role of particle morphology in laser assisted decontamination was studied.•A nano-second pulsed Nd-YAG laser was used.•UO2 and ThO2 particulates were used as the test contaminant.•Decontamination ...Efficiency (DE) was strongly dependent on particle morphology.•Higher values of DE were obtained for UO2 and milled ThO2 particulates.
This work explores laser assisted removal of uranium-di-oxide and thorium-di-oxide particulates from zircaloy substrate. An electro-optically Q switched Nd-YAG laser operating on three wavelengths of 1064 nm, 532 nm, 355 nm was used as the cleaning tool to compare the efficiency of the decontamination process. Laser assisted surface cleaning that offers the dual advantage of remote operation and minimizing the generation of secondary waste has therefore emerged as the most attractive technique with regard to decontamination of radioactive surface. In case of loose contamination wherein the contaminant particulates are often attached to the substrate surface by short range van-der-wall’s force, the absorption of energy from the incident radiation field by both particulates and substrate can contribute towards generation of cleaning force leading to expulsion of the particulates. It was found that laser parameters like its wavelength, fluence, number of exposures and particulate shape/size play an important role in the cleaning process. A single laser exposure with a fluence of ∼0.3–0.5 J/cm2 was found to be enough to obtain decontamination efficiency of ∼70–80% while removing the contaminants from zircaloy substrate. Subsequent exposure of laser pulses to the contaminants further increases the efficiency of cleaning. Decontamination efficiency was found to be always higher for uranium-di-oxide particulates than virgin thorium-di-oxide particulates under identical cleaning conditions. However, decontamination efficiency of milled thorium-di-oxide particulates was found to be marginally higher than uranium-di-oxide particulates.
Tropical soils are often deeply weathered and vulnerable to degradation having low pH and unfavorable Al/Fe levels, which can constrain crop production. This study aims to examine nitrogen-enriched ...novel biochar co-composts prepared from rice straw, maize stover, and gram residue in various mixing ratios of the biochar and their feedstock materials for the amelioration of acidic tropical soil. Three pristine biochar and six co-composts were prepared, characterized, and evaluated for improving the chemical and biological quality of the soil against a conventional lime treatment. The pH, cation exchange capacity (CEC), calcium carbonate equivalence (CCE) and nitrogen content of co-composts varied between 7.78-8.86, 25.3-30.5 cmol (p
+
) kg
−1
, 25.5-30.5%, and 0.81-1.05%, respectively. The co-compost prepared from gram residue biochar mixed with maize stover at a 1:7 dry-weight ratio showed the highest rise in soil pH and CEC, giving an identical performance with the lime treatment and significantly better effect (p < .05) than the unamended control. Agglomerates of calcite and dolomite in biochar co-composts, and surface functional groups contributed to pH neutralization and increased CEC of the amended soil. The co-composts also significantly (p < .05) increased the dehydrogenase (1.87 µg TPF g
−1
soil h
−1
), β-glucosidase (90 µg PNP g
−1
soil h
−1
), and leucine amino peptidase (3.22 µmol MUC g
−1
soil h
−1
) enzyme activities in the soil, thereby improving the soil's biological quality. The results of this study are encouraging for small-scale farmers in tropical developing countries to sustainably reutilize crop residues via biochar-based co-composting technology.
BACKGROUND AND AIMS: New maize (Zea mays) hybrids outperformed old ones even at reduced N rates. Understanding the mechanisms of the differences in performance between newer and older hybrids under N ...deficiency could provide avenues for breeding maize cultivars with large yield under N deficiency, and reduce environmental pollution caused by N fertilizers. METHODS: N deficiency effects on grain weight, plant weight, harvest index, leaf area and photosynthetic traits were studied in the field for six maize hybrids released during the past 50 years to compare their tolerance and to explore their physiological mechanisms. KEY RESULTS: N deficiency decreased grain yield and plant weight in all hybrids, especially in the older hybrids. However, there was no significant difference in harvest index, rate of light-saturated photosynthesis (Psubscript sat) 20 d before flowering, leaf area or plant weight at flowering between the N-deficient and control plants of all hybrids. Dry matter production after flowering of the N-deficient plants was significantly lower than that of the control plants in all hybrids, especially in the older hybrids, and was mostly due to differences in the rate of decrease in photosynthetic capacity during this stage. The lower Psubscript sat of the older hybrids was not due to stomatal limitation, as there was no significant difference in stomatal conductance (gsubscript s) and intercellular CO₂ concentration (Csubscript i) between the hybrids. N deficiency accelerated senescence, i.e. decreased chlorophyll and soluble protein contents, after anthesis more for the earlier released hybrids than for the later ones. N deficiency decreased phosphoenolpyruvate carboxylase (PEPCase) activity significantly more in older hybrids than newer hybrids, and affected the maximal efficiency of PSII photochemistry (Fv/Fm) only in the old hybrids and at the late stage. CONCLUSIONS: Compared with older (earlier released) hybrids, newer (later released) hybrids maintained greater plant and grain weight under N deficiency because their photosynthetic capacity decreased more slowly after anthesis, associated with smaller non-stomatal limitations due to maintenance of PEPCase activity, and chlorophyll and soluble protein content.
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