Some physical properties of rare-earth chlorides in aqueous solution

The aqueous solution behavior of some rare-earth chlorides has been investigated at 25° C. in the concentration range between 0.02 molal and saturation. Density measurements on solutions of lanthanum, neodymium, samarium, gadolinium, dysprosium, erbium, and ytterbium chlorides were carried out by a pycnometric method with an estimated accuracy of 1 x 10-5 gm.per ml. From the density data the apparent molal volumes for these rare-earth chlorides were calculated. The apparent molal volume data for each rare-earth chloride were expressed as a function of the square root of the molality by a five-parameter power series from which partial molal volumes were calculated. Conductance measurements on solutions of these rare-earth chlorides were carried out over the same concentration range using the conventional alternating-current technique. In addition, the solubilities of the rare-earth chlorides at 25° c. were determined

Biological Control of Mycotoxigenic Fungi and Their Toxins: An Update for the Pre-Harvest Approach

Over recent decades, laboratory and field trial experiments have generated a considerable amount of data regarding the promising use of beneficial microorganisms to control plant diseases. Special attention has been paid to diseases caused by mycotoxigenic fungi owing to their direct destructive effect on crop yield and the potential production of mycotoxins, which poses a danger to animal and human health. New legislative initiatives to restrict the use of the existing commercial chemical pesticides have been an incentive for developing and registering new bio-pesticides. In this book chapter, we discuss up to-date pre-harvest biological control agents against mycotoxigenic fungi and their respective toxins. We will focus on the different modes of action of the most frequently studied biological control agents. Furthermore, a comprehensive overview on their ability to suppress mycotoxin biosynthesis will be discussed

Presence of Borrelia burgdorferi sensu lato antibodies in the serum of patients with abdominal aortic aneurysms

Infectious agents are likely to play a role in the pathogenesis of chronic inflammatory diseases, including abdominal aortic aneurysms (AAAs). The goal of this study was to determine if Borrelia burgdorferi sensu lato (sl), a microorganism responsible for Lyme disease, is involved in the etiology of AAAs. The presence of serum antibodies against B. burgdorferi sl was measured with enzyme-linked immunosorbent assay (ELISA) and confirmed by Western blotting in 96 AAA and 108 peripheral artery disease (PAD) patients. Polymerase chain reaction (PCR) was used for the detection of Borrelia-specific DNA in the aneurysm wall. Among AAA patients 34% and among PAD patients 16% were seropositive for B. burgdorferi sl antibodies (Fisher’s exact test, p = 0.003; odds ratio [OR] 2.79; 95% confidence interval [CI] 1.37–5.85). In the German general population, 3–17% are seropositive for Borrelia antibodies. No Borrelia DNA was detected in the aneurysm wall. Our findings suggest a relationship between AAAs and B. burgdorferi sl. We hypothesize that the underlying mechanism for B. burgdorferi sl in AAA formation is similar to that by the spirochete Treponema pallidum; alternatively, AAAs could develop due to induced autoimmunity via molecular mimicry due to similarities between some of the B. burgdorferi sl proteins and aortic proteins

Polarization statistics of extra-solar systems

We have analysed the optical polarimetric properties of nearby intermediate-late type MS stars and examined in some detail the pecularities displayed by those known to have planets. We find that: i) the polarization degree is not strictly correlated with the presence of planets; ii) there is a lack of high eccentricity planets at high optical linear polarization levels; iii) no clear correlation is seen between metallicity and polarization amongst extra-solar systems; iv) the contribution to the polarization by the interstellar medium seems to become effective only after ~70 pc.Comment: 4 pages, 5 postscript figures, 1 table; Accepted for publication in Astronomy and Astrophysic

Topology at the Planck Length

A basic arbitrariness in the determination of the topology of a manifold at the Planck length is discussed. An explicit example is given of a `smooth' change in topology from the 2-sphere to the 2-torus through a sequence of noncommuting geometries. Applications are considered to the theory of D-branes within the context of the proposed $M$(atrix) theory.Comment: Orsay Preprint 97/34, 17 pages, Late

Reconstructing Quantum Geometry from Quantum Information: Spin Networks as Harmonic Oscillators

Loop Quantum Gravity defines the quantum states of space geometry as spin networks and describes their evolution in time. We reformulate spin networks in terms of harmonic oscillators and show how the holographic degrees of freedom of the theory are described as matrix models. This allow us to make a link with non-commutative geometry and to look at the issue of the semi-classical limit of LQG from a new perspective. This work is thought as part of a bigger project of describing quantum geometry in quantum information terms.Comment: 16 pages, revtex, 3 figure

Evaluation of mycotoxin content in soybean (Glycine max l.) grown in Rwanda

Soybean is a critical food and nutritional security crop in Rwanda. Promoted by the Rwandan National Agricultural Research System for both adults and as an infant weaning food, soybean is grown by approximately 40% of households. Soybean may be susceptible to the growth of mycotoxin-producing moulds; however, data has been contradictory. Mycotoxin contamination is a food and feed safety issue for grains and other field crops. This study aimed to determine the extent of mycotoxin contamination in soybean, and to assess people’s awareness on mycotoxins. A farm-level survey was conducted in 2015 within three agro-ecological zones of Rwanda suitable for soybean production. Soybean samples were collected from farmers (n=300) who also completed questionnaires about pre-and post-harvest farm practices, and aflatoxin awareness. The concentration of total aflatoxin in individual soybean samples was tested by enzymelinked immunosorbent assay (ELISA) using a commercially-available kit. Other mycotoxins were analyzed using liquid chromatography-mass spectrometry (LCMS/ MS) on 10 selected sub samples. Only 7.3% of the respondents were aware of aflatoxin contamination in foods, but farmers observed good postharvest practices including harvesting the crop when the pods were dry. Using enzyme-linked immunosorbent assay (ELISA), only one sample had a concentration (11 μg/kg) above the most stringent EU maximum permitted limit of 4 μg/kg. Multi-mycotoxins liquid chromatography-mass spectrometry (LC-MS/MS) results confirmed that soybeans had low or undetectable contamination; only one sample contained 13μg/kg of sterigmatocystine. The soybean samples from Rwanda obtained acceptably low mycotoxin levels. Taken together with other studies that showed that soybean is less contaminated by mycotoxins, these results demonstrate that soybean can be promoted as a nutritious and safe food. However, there is a general need for educating farmers on mycotoxin contamination in food and feed to ensure better standards are adhered to safeguard the health of the consumers regarding these fungal secondary metabolites.Key words: soybean, safety, mould, aflatoxin, mycotoxins, sterigmatocystine, ELISA, LC-MS/MS, Rwand

A polyphasic approach for characterization of a collection of cereal isolates of the Fusarium incarnatum-equiseti species complex

"Available online 22 June 2016"DNA-based phylogenetic analyses have resolved the fungal genus Fusarium into multiple species complexes. The F. incarnatum-equiseti species complex (FIESC) includes fusaria associated with several diseases of agriculturally important crops, including cereals. Although members of FIESC are considered to be only moderately aggressive, they are able to produce a diversity of mycotoxins, including trichothecenes, which can accumulate to harmful levels in cereals. High levels of cryptic speciation have been detected within the FIESC. As a result, it is often necessary to use approaches other than morphological characterization to distinguish species. In the current study, we used a polyphasic approach to characterize a collection of 69 FIESC isolates recovered from cereals in Europe, Turkey, and North America. In a species phylogeny inferred from nucleotide sequences from four housekeeping genes, 65 of the isolates were resolved within the Equiseti clade of the FIESC, and four isolates were resolved within the Incarnatum clade. Seven isolates were resolved as a genealogically exclusive lineage, designated here as FIESC 31. Phylogenies based on nucleotide sequences of trichothecene biosynthetic genes and MALDI-TOF MS (Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry) were largely concordant with phylogeny inferred from the housekeeping gene. Finally, Liquid Chromatography (Time-Of-Flight) Mass Spectrometry [LC-(TOF-)MS(/MS)] revealed variability in mycotoxin production profiles among the different phylogenetic species investigated in this study.This work was supported by the EU project EC KBBE-2007-222690-2 MYCORED