Survival of Bradyrhizobium sp. (Arachis) on fungicide-treated peanut seed in relationship to plant growth and yield

Survival and viability of Bradyrhizobium inoculant on fungicide-treated peanut seed and the resulting effects on nitrogen fixation, plant growth and seed yield were determined. Vitavax and Benomyl had the most and least lethal actions against Bradyrhizobium strains grown on YEM medium containing a fungicide, respectively, while Thiram and Captan effects were intermediate. Survival of Bradyrhizobium USDA 3384 and USDA 3456, as single strain peat inoculants, on peanut (Arachis hypogaea L. var. Florunner) seeds treated with Benomyl or Vitavax at the rate of 3g/kg seed was also examined. Both fungicides inhibited the growth and affected the survival of strain USDA 3384 on peanut seed. Vitavax killed the inoculant in 9 h. In contrast, USDA 3456 resisted both fungicides, and survived for up to 72h. Nodule formation on greenhouse-grown plants inoculated with USDA 3384 was inhibited by all fungicides. Shoot dry weight and plant nitrogen content significantly decreased as compared to controls. Fungicides, except Vitavax, had a slight effect on nodulation and plant growth when USDA 3456 was used as inoculant. The agronomic importance of fungicide-inoculant interaction was examined in field experiments conducted in Egypt in soil free of peanut-nodulating Bradyrhizobium, where seeds were treated with a combination of two fungicides and a single strain peat inoculant of either USDA 3384 or USDA 3456. All fungicides decreased nodulation, nitrogen fixation, plant growth and seed yield, especially with USDA 3384 as inoculant. Fungicides inhibited viability and survival of Bradyrhizobium on peanut seeds which decreased nodule formation leading to reduced peanut seed yield.     

Radiostimulation of barley seeds treated with 2-mercaptoethanol of ascorbate

In model experiments with Bonus barley,where the growth of a fraction of the seedlings is retarded by a raised thiol content, obtained through treatment with 2-mercaptoethanol, stimulation of growth is reproducibly induced by low doses of γ-rays. As illustrated by a probit representation of seedling heights, and by the decrease of coefficients of variation, the radiostimulation is restricted to that fraction of seedlings which exhibits a suppressd growth. The validity of the model to natural situations was sustained in studies of the variety Impala, which was shown by Fendrik and Bors to respond regularly to stimulating doses of X-rays. In this variety the response was shown to be restricted to a sub-population of seedlings with retarded growth, i.e. the same pattern as observed in thiol-treated Bonus barley.     

Edaphic factors and plant species distribution in a protected area in the desert of Bahrain Island

Effects of edaphic factors (salinity, pH, Na⁺, K⁺, Ca⁺⁺, CaCO₃, water holding capacity, and grain size) on the spatial distribution of plants were investigated. Soil was sampled at 22 stands. Sixteen plant species were recorded from these stands. Relation between edaphic factors and plant distribution was investigated using correlation statistical analysis. Distribution of some plants was found to be highly correlated with edaphic factor(s).     

Reduction of the human detective quantum efficiency due to lateral neural interactions

We present a simple representation of the lateral neural interactions of summation and subtraction in a situation involving quantum limited luminance increment detection. Lateral subtractive interactions would be expected to lower the measured quantum efficiency by up to a log unit. Lateral neural interactions can explain both the type and amount of decrease of human foveal quantum efficiency with target area reported by Cohn as well as the increase reported by Clark-Jones.     

Antimicrobial effect of different herbal plant extracts against different microbial population

This study evaluates the antimicrobial effects of ethanolic extract of five herbal plants; Guava (Psidium guajava), Sage (Salvia officinalis), Rhamnus (Ziziphusspina Christi), Mulberry (Morusalba L.), and Olive (Oleaeuropaea L) leaves against several microbial population representing Gram positive, Gram negative and Mollicutes; S. aureus, E. coli, Pasteurella multocida, B. cereus, Salmonella Enteritidis and M. gallisepticum using standard agar disc diffusion technique and minimal inhibitory concentration (MIC). Different extracts reveal variable results against the microorganism under study. All extracts have no antibacterial potency for Mycoplasma gallisepticum except Psidium guajava. The results of minimal inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) of the extracts against the six bacteria ranged from 625 to 5000 μg/ml. The used herbal extract could inhibit the selected microorganism under study with variable minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC).     

Model‐assisted identification of metabolic engineering strategies for Jatropha curcas lipid pathways

Efficient approaches to increase plant lipid production are necessary to meet current industrial demands for this important resource. While Jatropha curcas cell culture can be used for in vitro lipid production, scaling up the system for industrial applications requires an understanding of how growth conditions affect lipid metabolism and yield. Here we present a bottom‐up metabolic reconstruction of J. curcas supported with labeling experiments and biomass characterization under three growth conditions. We show that the metabolic model can accurately predict growth and distribution of fluxes in cell cultures and use these findings to pinpoint energy expenditures that affect lipid biosynthesis and metabolism. In addition, by using constraint‐based modeling approaches we identify network reactions whose joint manipulation optimizes lipid production. The proposed model and computational analyses provide a stepping stone for future rational optimization of other agronomically relevant traits in J. curcas.     

Straightforward method for calibration of mechanistic cation exchange chromatography models for industrial applications

Mechanistic modeling of chromatography processes is one of the most promising techniques for the digitalization of biopharmaceutical process development. Possible applications of chromatography models range from in silico process optimization in early phase development to in silico root cause investigation during manufacturing. Nonetheless, the cumbersome and complex model calibration still decelerates the implementation of mechanistic modeling in industry. Therefore, the industry demands model calibration strategies that ensure adequate model certainty in a limited amount of time. This study introduces a directed and straightforward approach for the calibration of pH-dependent, multicomponent steric mass action (SMA) isotherm models for industrial applications. In the case investigated, the method was applied to a monoclonal antibody (mAb) polishing step including four protein species. The developed strategy combined well-established theories of preparative chromatography (e.g. Yamamoto method) and allowed a systematic reduction of unknown model parameters to 7 from initially 32. Model uncertainty was reduced by designing two representative calibration experiments for the inverse estimation of remaining model parameters. Dedicated experiments with aggregate-enriched load material led to a significant reduction of model uncertainty for the estimates of this low-concentrated product-related impurity. The model was validated beyond the operating ranges of the final unit operation, enabling its application to late-stage downstream process development. With the proposed model calibration strategy, a systematic experimental design is provided, calibration effort is strongly reduced, and local minima are avoided.     

Comparaison de l’estimation du débit de filtration glomérulaire par le 99mTc-DTPA au radiotraceur de référence le 51Cr-EDTA comparativement aux méthodes basées sur la mesure de la créatininémie

Since the end of 2018, the distribution of the reference tracer for the measurement of glomerular filtration rate (GFR), the 51Cr-EDTA, is no longer provided by radiopharmaceutical companies around the world. In this study, we propose to compare the measurement of glomerular filtration rate by 99mTc-DTPA to that by 51Cr-EDTA. A double estimation of GFR by plasma clearance was performed in 12 patients, 10 of which were referred for GFR calculation prior to possible kidney donation. Linear regression coefficients and intraclass correlation coefficient (ICC) were calculated for the GFR measurement by 99mTc-DTPA, and by MDRD, CKD-EPI and Cockcroft and Gault formulas, relative to the 51Cr-EDTA measurement. The clearance measurement with 99mTc-DTPA is on average 7.25 [2.00; 14.96] mL/min/1.73m² higher than that of 51Cr-EDTA. The GFR measurement with 99mTc-DTPA showed a trend towards better agreement with the 51Cr-EDTA measurement in terms of linear regression parameters, but also in terms of ICC compared to the MDRD, CKD-EPI and Cockcroft and Gault methods. In conclusion, our study supports the use of the 99mTc-DTPA tracer in place of 51Cr-EDTA and shows a higher reliability compared to methods based on blood creatinine measurement.