Locomotor effects in sheep of alkaloids identified in Australian Tribulus terrestris

Fresh, mature, ungrazed Tribulus terrestris plant material was subjected to a standard alkaloid extraction procedure. The extract was fractionated by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). Two major alkaloid fractions were demonstrated. These fractions were identified by means of TLC, ultraviolet spectrofluorimetry (UVS) and HPLC, as the beta-carboline indoleamines harmane and norharmane. The extractable alkaloid content was determined to be 44 mg/kg dry matter. Synthetic harmane and norharmane were administered subcutaneously to sheep at a dose rate of 54 mg/kg. Both compounds caused similar nervous effects. The main effect observed was limb paresis, which in some sheep was body side blased. The clinical signs observed in the experimental sheep were consistent with those described for naturally occurring cases of Tribulus terrestris staggers. It was proposed that harmane and norharmane accumulate in tryptamine-associated neurones of the central nervous system, during months of tribulus ingestion, and gradually interact irreversibly with a specific neuronal gene DNA sequence.     

Economic and financial model to the mass-rearing of Macrolophus pygmaeus (Rambur) (Heteroptera: Miridae), a biological control agent against the tomato moth Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in protected culture

BACKGROUND

Tuta absoluta (Meyrick) is a major pest of tomato produced in glasshouses and open field, causing severe damages to crops, reducing the quality of tomato fruits. The current maintenance of the pest populations below the economic threshold is not achieved by natural and classical control, thus requiring the continuous application of biological control agents (BCAs), under an augmentative or inoculative approach. The present study aims to develop an economic and financial model to evaluate the commercial viability of a continuous mass production of Macrolophus pygmaeus (Rambur), a BCA commonly used against the tomato moth, Tuta absoluta, in protected culture. The estimations for our model were based on two approaches: the farm-level impact analysis and the benefit–cost analysis.

RESULTS

The results of the farm-level analysis show that the adoption of a more sustainable biological control approach is profitable for farmers and the benefit–cost analysis provides evidence that the investment on a new factory dedicated to the mass rearing of M. pygmaeus to control tomato moth populations generates a positive net present value (NPV) of 7.2 million euros, corresponding to an internal rate of return (IRR) of 28.4% per year.

CONCLUSION

Our results are in line with (i) the more recent European Commission proposals for a new Regulation on sustainable use of plant protection products, which includes the reduction of 50% the use and risk of chemical pesticides by 2030 and (ii) most of the existing literature which conclude that new projects on BCA production are worth investments. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Encounter with saturn: voyager 1 imaging science results

As Voyager 1 flew through the Saturn system it returned photographs revealing many new and surprising characteristics of this complicated community of bodies. Saturn's atmosphere has numerous, low-contrast, discrete cloud features and a pattern of circulation significantly different from that of Jupiter. Titan is shrouded in a haze layer that varies in thickness and appearance. Among the icy satellites there is considerable variety in density, albedo, and surface morphology and substantial evidence for endogenic surface modification. Trends in density and crater characteristics are quite unlike those of the Galilean satellites. Small inner satellites, three of which were discovered in Voyager images, interact gravitationally with one another and with the ring particles in ways not observed elsewhere in the solar system. Saturn's broad A, B, and C rings contain hundreds of "ringlets," and in the densest portion of the B ring there are numerous nonaxisymmetric features. The narrow F ring has three components which, in at least one instance, are kinked and crisscrossed. Two rings are observed beyond the F ring, and material is seen between the C ring and the planet.     

Anatomy of the patent ductus venosus in the cat

The biplanar mesenteric vein portovenograms of 10 cats with left divisional intrahepatic portosystemic shunts consistent with a patent ductus venosus (PDV) were reviewed. A corrosion cast of the hepatic portal vasculature was made post mortem from one individual that died post operatively following surgical attenuation of the shunting vessel. On the basis of the combined surgical, post mortem and imaging data, these left divisional shunts were found to have consistent anatomy, each having a straight vessel which drained into a venous ampulla before draining into the caudal vena cava at the level of the diaphragm. The left phrenic vein and left hepatic vein both entered the ampulla independently of the shunting vessel. The anatomical similarity between these findings in the cat and the PDV in the dog suggest that it is appropriate to describe this particular portosystemic shunt as a PDV.     

Evaluation and QTL mapping of phosphorus concentration in soybean seed

Phosphorus (P) is an essential macronutrient required for many biological and metabolic plant functions. Phosphate is the form of P used by plants. Reducing the amount of P in the seed can further aide breeding efforts to reduce the amount of P released into the environment due to the indigestibility of the complexes formed with metal ions. Analysis of the variation of phosphorus concentration in soybean seed under non-stressed conditions revealed that phosphorus ranged from 3,948.1 to 5,695.8???g/g total phosphorous (TP) in combined years. The averages for independent years were significantly different from one another. Quantitative trait loci (QTL) analysis of TP was performed to identify candidate gene(s) that is (are) involved in P accumulation in soybean seed. One putative QTL region was identified on chromosome 12 in the combined data that contained a phosphate transporter gene. Two additional suggestive QTL were identified on chromosomes 7 and 17 with chromosome 7 having both a phosphate transport gene and a ZIP transporter gene in the region of the QTL. There were additional genes in these regions that are involved in phosphate metabolism and transport.     

Uncertainty Analysis for Computationally Expensive Models with Multiple Outputs

Bayesian MCMC calibration and uncertainty analysis for computationally expensive models is implemented using the SOARS (Statistical and Optimization Analysis using Response Surfaces) methodology. SOARS uses a radial basis function interpolator as a surrogate, also known as an emulator or meta-model, for the logarithm of the posterior density. To prevent wasteful evaluations of the expensive model, the emulator is built only on a high posterior density region (HPDR), which is located by a global optimization algorithm. The set of points in the HPDR where the expensive model is evaluated is determined sequentially by the GRIMA algorithm described in detail in another paper but outlined here. Enhancements of the GRIMA algorithm were introduced to improve efficiency. A case study uses an eight-parameter SWAT2005 (Soil and Water Assessment Tool) model where daily stream flows and phosphorus concentrations are modeled for the Town Brook watershed which is part of the New York City water supply. A Supplemental Material file available online contains additional technical details and additional analysis of the Town Brook application.