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Nitrogen use efficiency, more specifically physiological nitrogen use efficiency depends primarily on management of N, one of the major essential nutrients. It is required in increased agricultural production and may possibly cause soil toxicity if fed in excess. Rate of N fertilizer application in fertile agricultural field and improved productivity in sterile soils require the improvement of NUE. A field experiment was therefore conducted to evaluate the effect of different N levels (N0, N50, N100 and N200) on rice genotypes. Vegetative plant growth was found to be reduced under N0 while improved at N200 level. Among the genotypes, highest PNUE (34.94) and correspondingly higher yield (7.15 ton ha−1) was observed for Krishna Hamsa. The other traits viz. plant height, no. of productive tillers and LAI exhibited higher values for Krishna Hamsa as well. Hence these can be utilized as physiological markers for the selection of rice genotypes efficient in N use.
Abstract
A rapid, stability indicating reverse phase liquid chromatographic method was developed for the determination of purity of Felodipine in active pharmaceutical substance form in the presence of its impurity and its degradation products. To develop the method which is also compatible to liquid chromatographic mass spectroscopic technique. The developed method is also used to determine the assay of Felodipine in bulk drug form. The drug is subjected to various stress conditions like acidic, basic, oxidation, UV light and thermal conditions. Considerable degradation was observed during base hydrolysis. Two degradation products were identified. The Waters Acquity UPLC BEH C18, 2.1 × 100 mm, 1.7 µm Column was used to achieve chromatographic separation. The gradient conditions, diluent and injection volume were optimized to achieve the acceptable resolution between impurities and its degradation products from Felodipine and to get good peak shapes. The masses were determined for main compound and its identified degradation products. Further, the characterization studies for main compound and its degradation products were performed using LCMSMS Q-TOF.
Deltamethrin, a well-known type 2 synthetic pyrethroid insecticide, is a widespread environmental toxicant. It has potential to accumulate in body fluids and tissues due to its lipophilic characteristics. The immune system is among the most sensitive targets regarding toxicity of environmental pollutants. Various methods are available in the literature to analyze deltamethrin (DLM) concentration in plasma and tissues, but regarding the immune organs, only one gas chromatography–tandem mass spectrometry (GC–MS/MS) method (on spleen tissues) has been reported. In the present investigation, a rapid and sensitive high-performance liquid chromatography (HPLC) method has been developed and validated to determine DLM concentration in plasma, thymus, and spleen using zaleplone as an internal standard. Liquid chromatography (LC) separation is performed on an Agilent Zorbax® C8 column (250 mm × 4.6 mm, i.d., 5 μm) with isocratic elution using a mobile phase consisting of acetonitrile–5 mM KH2PO4 (70:30, v/v) at a flow rate of 1 mL min−1. The lower limit of quantification (LLOQ) for DLM is 10 ng mL−1 (plasma, thymus, and spleen). The method has been validated in terms of establishing linearity, specificity, sensitivity, recovery, accuracy, and precision (intra- and inter-day) and stabilities study. This validated method was successfully applied to a pharmacokinetic and tissue distribution study of DLM in mice.
Abstract
The aim of the present study was to find the best extraction parameters to obtain the highest amounts of polyphenols and antioxidants from the walnut. Walnut kernels from ‘Alsószentiváni 117’ cultivar were used for extraction. The extraction methods were as the follows:
Method 1: shaking water-bath at 50 °C for 30 min.
Method 2: shaking water-bath at 50 °C for 30 min, then storing at 5 °C for 20 h.
Method 3: shaking water-bath at 40 °C for 30 min.
Method 4: shaking water-bath at 40 °C for 30 min, then storing at 5 °C for 20 h.
According to our results Method 1 showed the highest FRAP value (34.43 mg AAE g−1), the DPPH value (52,94%) and the highest HPLC peaks for chlorogenic acid, epicatechin and rutin were also seen in extracts obtained using Method 1. TPC values of Method 3 were 26.06 mg GAE g−1 for Method 1 it was 25.65 mg GAE g−1. The results of color values, L* and ΔE* were similar in all extracts as well. In our experiments extraction Method 1 proved to be better than others.
Abstract
Thermophysical properties of reversed TALSPEAK extractant (0.3 M D2EPHA/0.2 M TBP/n-dodecane) were not available in literature. Authors have experimentally measured and correlated several thermophysical properties of RT solvent like density, viscosity, refractive index, acid uptake and flash point. In this paper, results of these studies will be discussed in detail.
A Holstein-Friesian cow aged 6 years aborted twice at 3-4 months of gestation. On rectal palpation a growth was palpable in the apex of one uterine horn. The growth was removed by right flank laparotomy under sedation and paravertebral nerve block. The growth was diagnosed to be a fibroma. The cow conceived and calved normally after the operation.
The paper deals with morphological and physiological variability of Colletotrichum falcatum Went on different temperature, pH, medium, nitrogen sources, carbon sources and also first time reporting of the two National Pathotypes from North East Zone of Uttar Pradesh, India. Thirty-four isolates were isolated from infected samples of different sugarcane varieties during survey and maintained on Oat Meal Agar (OMA) slants as well as on the Petri dishes at 30±1 °C. These isolates showed the variability in their optimum radial growth pattern. The optimum radial growth of all isolates was recorded at 8, 10 and 12 days. Six isolates exhibited maximum radial growth (90 mm diam) in 8 days, while the other 10 isolates attained same growth in 10 days. Remaining 14 isolates took 12 days to attain same growth. Pathogenecity of 34, isolates has been tested on 12 host differentials of sugarcane genotypes only SES594 was found resistant and others showed the variable response, while highly susceptible reaction to be found in three isolates (R0704, R0720 and R0728). These three isolates gave maximum spores on OMA followed by PDA medium and higher dry mycelium weight was observed in Richard’s liquid medium as compared to others. The maximum growth was recorded for these three isolates on potassium nitrate and sodium nitrate as nitrogen sources. Growth regulators like IAA and IBA at lower concentration enhances the growth while higher concentration showed adverse affect. When these three isolates were compared with the national level pathotypes, viz. Cf01 (Co1148), Cf08 (CoJ64) and Cf09 (CoS767) reaction in differential and spores inoculation technique it was found that isolates showed similar reaction like National Level pathotypes. Hence, it was concluded that these three isolates are belonging to new pathotypes.
Three-year (2007/2008–2009/2010) field experiment was conducted at the Directorate of Water Management Research Farm under Deras command in Odisha, India to assess the crop yield, irrigation water use efficiency (WUE), sustainable yield index (SYI), land utilization index (LUI) and changes in soil organic carbon (SOC) for dominant rice systems, viz. rice-maize-rice, rice-cowpea-rice, rice-sunflower-rice, rice-tomato-okra and rice-fallow-rice. Results revealed that crop yield, in terms of total system productivity (TSP) increased by 273, 113, 106 and 58% in rice-tomato-okra, rice-sunflower-rice, rice-maize-rice and rice-cowpea-rice, respectively, when compared to rice-fallow-rice. Irrigation WUE was 49–414% greater in rice-based diversified systems than the existing rice-fallow-rice (2.98 kg ha−1 mm−1). The SYI ranged from 0.65 to 0.75 indicating greater sustainability of the systems. Three crops in a sequence resulted in greater LUI and production efficiency compared to rice-fallow-rice. The gross economic return and benefit-cost ratio was in the order: rice-tomato-okra > rice-maize-rice > rice-sunflower-rice > rice-cowpea-rice > rice-fallow-rice. The SOC storage ranged from 40.55 Mg ha−1 in rice-fallow-rice to 46.23 Mg ha−1 in rice-maize-rice system. The other systems had also very close values of SOC storage with the rice-maize-rice system; there was a positive change of SOC (7.20 to 12.52 Mg ha−1) for every system, with highest in rice-maize-rice system and the lowest in rice-fallow-rice. It is concluded that the appropriate rice-based system would be rice-tomato-okra followed by rice-maize-rice, rice-sunflower-rice and rice-cowpea-rice. Rice-fallow-rice is not advisable because of its lower productivity, lower LUI and economic return.
Abstract
An accelerator mass spectrometry (AMS) facility for measurements of 10Be has been developed by upgrading the 15UD Pelletron accelerator at Inter-University Accelerator Centre (IUAC), New Delhi. Details of the up gradation of the facilities and the measurement procedure are described briefly. Chemical processing for the separation of 10Be from manganese nodules and results of recent experiments on 10Be are presented.
Abstract
A male cattle calf was detected as subclinically and naturally infected with Mycobacterium avium subspecies paratuberculosis (MAP) by a series of antemortem and postmortem tests. The MAP infection was identified by strong antibody and cell-mediated immune (CMI) response by a commercial ELISA kit and an intradermal Johnin test, respectively, in the initial antemortem examination. The antemortem status of the calf was further confirmed by MAP-specific interferon gamma (IFN-γ) response. For detection of IFN-γ response, MAP-specific IFN-γ release assays (IGRAs): (a) immuno capture ELISA (IC-ELISA) and (b) ELISPOT was employed. In addition, the presence of intracellular cytokine IFN-γ was detected by flow cytometry. For all cytokine assays, MAP-specific recombinant antigens HSP65 and 35 kDa were employed to overcome the poor sensitivity and specificity resulting from the use of Johnin, the crude protein purified derivative of MAP. Postmortem examination of the MAP-infected/suspected cattle calf did not reveal any pathognomonic gross lesions in the gastro-intestinal tract. Histopathological examination of multiple organs showed the presence of epithelioid cells/macrophages and edematous lesions in the mesenteric lymph nodes suggestive of MAP; however, no granulomas were observed in the intestinal tract. The necropsy samples of rectum and mesenteric lymph nodes were positive for isolation of MAP by culture in the BACTEC™ MGIT™ 960 system, and acid fast bacilli were demonstrated by fluorescence microscopy confirming the infection. Due to differential and complex expression patterns of MAP antigens reported in literature, a combination of assays such as those based on IGRAs and antibody detection is essential. Therefore, the current experimental evidence confirms the efficacy of the approach adopted. However, further studies will be needed to understand the optimal combination MAP-specific antigens for use in IGRAs or antibody assays that can be used for detecting MAP infection in every stage of the disease.
