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, acetoxy or aryl groups at α - and β -positions. Some of the compounds have comparable activity to that of the commercial nematicide, aldicarb. Keywords: aldicarb, chemical structure, juvenile mortality, nematicide, nematode control. Several kinds of compounds, either isolated from plants or synthesised in

In: Nematologica

. 2017 ; Xia et al . 2018 ). However, the relationship between the free water and the porous structure of waterlogged archeological wood is rarely reported. Moreover, the influence and mechanism of changes in the chemical structure, cellulose crystallite structure and porous structure of waterlogged

In: IAWA Journal

Chemical and anatomical properties of tumorous and normal wood of Quercus robur L. subsp. robur were compared. Tumorous growth appeared as a result of topping stress. Orientation of cells was severely disrupted in the affected wood. In cross section, aspects of cells changed abruptly from transverse to longitudinal, and in tangential section all wood elements appeared to turn around each other like a fingerprint. Vessel elements and fibres of affected wood were shorter than those of healthy wood. The vessels of affected wood were smaller in diameter especially in the earlywood. On the other hand, multiseriate ray height was shorter than that of normal wood. In addition, perforated ray cells occurred. The ray and axial parenchyma cells of tumorous wood contained dark coloured phenolic compounds. Normal wood had calcium oxalate crystals, while tumorous wood did not. Chemical analyses showed that hemicellulose content and solubility rates in 1% NaOH, cold water, hot water, and alcohol- benzene were higher than those of normal wood. Cellulose and ash contents of tumorous wood were slightly lower than in normal wood. In addition, air-dry specific gravity of tumorous wood was higher than that of normal wood.

In: IAWA Journal
In: Pristionchus pacificus

layer obtained from the methanol extract by solvent partitioning caused 100% mortality of PWN at low concentrations of 125 and 63 μ g ml − 1 , respectively. One potent nematicidal compound was isolated from the stem bark of P. americana and its chemical structure was determined to be isoobtusilactone A

In: Nematology

mainly mass spectroscopy and nuclear magnetic resonance (NMR) spectroscopy, the chemical structure was determined to be that of pyochelin (a mixture of two interconvertible diastereoisomers, pyochelin I and II). Pyochelin exposure reduced the viability of pine callus. Compared with phenylacetic acid, a

In: Nematology
Author: Karel Sláma

(1961) as a common sesquiterpenoid alcohol farnesol (3,7,11-trimethyldodeca-2,6,10-trien-1-ol), which was the first JH-active compound with a determined chemical structure. Farnesol, its derivative farnesylmethylether ( Schmialek, 1963b ) and the related sesquiterpenoids ( Schmialek, 1963c ) brought JH

In: Terrestrial Arthropod Reviews

The plant qinghao 青蒿 (Artemesia annua) has provided the world with a valuable anti-malarial drug (qinghaosu 青蒿素). Another useful anti-malarial drug (febrifugine) of Chinese origin can be extracted from the shrub Dichroa febrifuga (changshan) but, unlike qinghaosu, its chemical structure is relatively simple and it could be easily synthesised in a pharmaceutical factory. However, the presence of two chiral centres in the molecule makes this unsuitable for pharmacological use as only one of the four isomers (the one found naturally) kills the malarial parasite, but all four isomers (as in the synthetic material) have serious adverse side effects. Encouraging African governments to consider growing Dichroa febrifuga as an alternative to the expensive and scarce qinghaosu should be considered.

In: Asian Medicine

Axial resin canals in wood are distinguished into two types based on the morphology of epithelial cells; resin canals with narrow canals and thick-walled epithelial cells (Type I), and resin canals with wide canals and thin-walled epithelial cells (Type II). Following studies on Norway spruce (Type I), the distribution of non-cellulosic polysaccharides in axial resin canals of Scots pine (Type II) is reported here using cytochemical and immunocytochemical methods. The distribution of (1→4)-β-galactan (LM5), (1→5)-α-arabinan (LM6), homogalacturonan (LM19, LM20), xyloglucan (LM15), xylan (LM10, LM11) and mannan (LM21, LM22) epitopes were examined. Axial resin canal complexes in the xylem were composed of canal, epithelium and subsidiary cells (parenchyma and strand tracheids). Strand tracheids were absent in axial resin canals in the phloem. Strand tracheids showed a completely different ultrastructure and chemistry from normal mature tracheids and other types of axial resin canal cells. Immunolocalization of non-cellulosic polysaccharides in axial resin canals showed an overall similar cell wall composition in epithelial cells and subsidiary parenchyma between the xylem and phloem. All types of axial resin canal cells in both xylem and phloem contained homogalacturonan (HG), rhamnogalacturonan-I (RG-I) and xyloglucan with a high variation in amount and chemical structure depending on cell wall region and between cell types. In particular, epithelial cell walls facing the canal showed significant differences in HG distribution from other epithelial cell wall regions. No xylan and mannan epitopes were detected in any of axial resin canal cells. Together, our results suggest that the chemistry of axial resin canal cells in Scots pine may be highly compartmentalized depending on functional differences between both cell types and cell wall regions.

In: IAWA Journal
The Historic Work and Lives of Elizabeth Cavert Miller and James A. Miller
The Understanding, Prevention and Control of Human Cancer is an account of how a married couple opened understanding of environmental carcinogenesis. Elizabeth Cavert and James A. Miller showed that enzymes of the human body activate and enable otherwise benign organic chemicals to combine with DNA in such a manner that cancer results. Their work is of particular note because cancer causes more loss of life-years than the sum of all other causes of death—and, as the President’s (USA) Cancer Panel warned, environmental carcinogenesis is a form of cancer that has been previously “grossly underestimated”. The Millers’ cancer research led to tests that identify dangerous chemicals which in turn permits prevention and thus the control of human cancer.