bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure and insecticidal activities of pyrethroids available through new methods of synthesis
Authors: Greuter Hans , Bissig Peter , Martin Pierre , Flück Victor , Gsell Laurenz
Published: November 2006

Starting from derivatives of cyclobutanone the synthesis is described of α‐cyano‐3‐phenoxybenzyl esters of 2,2‐dimethylcyclopropanecarboxylic acid, substituted in the 3‐position of the cyclopropane ring by an alkoxy, alkylthio, phenoxy or phenylthio group. The insecticidal activities of these synthetic pyrethroids towards adult Musca domestica, and larvae of Aedes aegypti, Spodoptera littoralis and Heliothis virescens are reported and compared with known pyrethroids.
The cross‐resistance to pyrethrins and eight synthetic pyrethroids, of an organophosphorus‐resistant strain of the rust‐red flour beetle Tribolium castaneum (herbst)
Authors: Lloyd C. John , Ruczkowski George E.
Published: November 2006

Comparisons with standard susceptible insects showed that a strain of Tribolium castaneum, with a specific resistance to malathion and its carboxylic ester analogues, had no cross‐resistance to topical applications of natural pyrethrins. Another strain of T. castaneum, showing resistance to many organophosphorus (OP) insecticides, was cross‐resistant to pyrethrins ( × 34) and eight synthetic pyrethroids also applied topically; least cross‐resistance occurred with resmethrin ( × 2.2), bioresmethrin ( × 3.3) and phenothrin ( × 4.0). Generally larger resistance factors were recorded with formulations synergised by piperonyl butoxide (PB). The greatest cross‐resistance encountered was with unsynergised tetramethrin ( × 338). Apart from tetramethrin, factors of synergism did not exceed 5.7 with either the susceptible or multi‐OP resistant strains. PB antagonised six of the nine pyrethroids against the multi‐OP resistant strain. Antagonism also occurred with two of these six, permethrin (cis: trans ratio 1:3) and 5‐prop‐2‐ynylfurfuryl ( 1RS)‐cis,trans‐chrysanthemate (‘Prothrin’), against the susceptible strain. Considering only formulations without the synergist, the most effective compounds against the susceptible strain, relative to pyrethrins, were bioresmethrin (2.7) and permethrin (2.4). Similarly with the multi‐OP resistant strain the most effective compounds were bioresmethrin (28), resmethrin (14) and permethrin (6.6). Thus the LD50 (the dose required to kill 50% of the test species) for bioresmethrin against the resistant strain (0.14 μg) only slightly exceeded the LD50 for pyrethrins against the susceptible strain (0.12 μg).
The herbicidal activity of 2‐alkyl‐2‐cyanoacetanilides
Authors: Geissler Arthur E. , Huppatz John L. , Phillips John N.
Published: November 2006

The pre‐emergent herbicidal activity of 2‐alkyl‐2‐cyanoacetanilide derivatives (a new class of anilide herbicides) is reported and the relationship between structure and activity examined. The compounds appear to act by inhibiting development of root growth. Comparisons with 2‐chloroacetanilide herbicides reveal similarities and differences which suggest that, whilst both groups may interact at a similar cellular site, a different reaction mechanism may be involved.
The effect of three fungicides, specific for the control of rice blast disease, on the growth and melanin biosynthesis by Pyricularia oryzae cav.
Authors: Woloshuk Charles P. , Wolkow Penelope M. , Sisler Hugh D.
Published: November 2006

Tricyclazole (EL 291), 4,5‐dihydro‐4‐methyltetrazolo [1,5‐a] quinazolin‐5‐one (PP 389), and pyroquilon (CGA 49104) were studied to determine the effects on growth and melanin biosynthesis by Pyricularia oryzae in vitro. The three fungicides were essentially devoid of toxicity to P. oryzae at concentrations up to 50 ug ml−1 but each selectively inhibited melanin biosynthesis at much lower concentrations. Inhibition of melanin biosynthesis resulted in the accumulation of 2‐hydroxyjuglone and flaviolin. The study indicated that the three compounds act by a similar mechanism in P. oryzae..
Spray retention and distribution on apple trees
Authors: Herrington Pamela J. , Mapother Harry R. , Stringer Austin
Published: November 2006

Total deposits and their distribution on bush and dwarf hedgerow apple trees, sprayed at the late dormant and full foliage stages with a copper fungicide by five different methods, were estimated by colorimetric determination of the acid‐extracted copper from all the tree parts, and for comparison purposes were converted to equivalent volumes retained. The bush trees were sprayed by hand lance (4500 litresha‐1), by automatic nozzle mast sprayer (2250 litres ha−1), by conventional air‐blast sprayer at medium volume (1125 litres ha−1) and low volume (560 litres ha−1), and by hand‐directed ultra‐low‐volume (ULVH) fan‐assisted spinning‐disc sprayer (6 litres ha−1). The hedgerow trees were sprayed by conventional air‐blast sprayer at low volume (560 litres ha−1) and by an experimental tractor‐mounted ultra‐low‐volume air‐blast sprayer (45 litres ha−1). At the late dormant stage, the bush trees retained only 9–22 % of the total spray applied by all methods, except that those sprayed by the hand‐directed ULVH sprayer retained 57%. At the full foliage stage, when most of the spray was deposited on the leaves, retention for all methods of application was 22–37%. The hedgerow trees at late dormancy retained 6% of the spray applied in low volume and 10% of that by tractor‐mounted ultra‐low‐volume methods, but at full foliage, retention was 25 and 63 %, respectively. On both types of tree the proportions of the spray deposited on the tree components were related to the surface areas of those components.
Properties of dicarboximide‐resistant strains of Botrytis cinerea
Authors: Davis Richard P. , Dennis Colin
Published: November 2006

Dicarboximide‐resistant strains of Botrytis cinerea were isolated from natural substrates and also produced in the laboratory. All these strains exhibited a similar degree of resistance to the dicarboximide fungicides iprodione and vinclozolin, and this resistance persisted in the absence of the fungicides. The natural frequency of resistance to both chemicals was approximately three in 107 conidia but could be enhanced by up to 1000 times after a single exposure to sub‐lethal concentrations of either chemical. Mycelium of the resistant strains was able to infect fruit and vegetables to a similar extent as that of sensitive strains, although infection of carrot roots was markedly less aggressive. The resistant strains were separable into two groups according to their growth habit on culture media. Both groups were relatively slow growing and showed a marked lack of sporulation compared with most sensitive strains. This lack of sporulation may account for the apparent failure of resistant strains to increase rapidly in strawberry plantations that had received dicarboximide sprays in successive seasons.
A technique for studying the biological efficiency of small droplets of pesticide solutions and a consideration of the implications
Authors: Munthali David C. , Scopes Nigel E. A.
Published: November 2006

A simple bioassay technique is described for small, uniformly‐sized droplets of pesticide solutions obtained by use of a microtip spray nozzle. A soluble fluorescent tracer was added to the spraying solution; droplets of the solution were sprayed on leaf discs and counted under a microscope with the aid of an ultraviolet lamp. The technique was used to study the relationships between the number of drops, their size and the dicofol concentration, on the mortality of Tetranychus urticae eggs. LD50 values decreased as the drop size was reduced; the concentration of the pesticide also affected the LD50 values. The technique can be used to study the biological efficiency of ultra‐low volume pesticide formulations in the laboratory.
Effect of fungicides on the physiology of plants. Part IV: Protection of cellular organelles of senescent wheat leaves by carbendazim
Authors: Tripathi Ram K. , Tandon Komal , Schlösser Eckart , Hess Wilford M.
Published: November 2006

Wheat leaves (cv. Kormoran) floated on water and kept in darkness turned yellow. This induced senescence was accompanied by a loss of electrolytes and amino acids, and by disorganisation of all cellular organelles except cell walls. Treatment with a solution of carbendazim (20 μg ml−1) prevented the leakage of electrolytes and disorganisation of cell organelles. At 100 μg ml−1, the fungicide did not prevent the damage caused by senescence but stimulated the loss of electrolytes from the leaves. It is proposed that one of the major mechanisms of the antisenescent activity of carbendazim is its protective effect on membranes.
Measured and simulated behaviour of fluometuron, aldoxycarb and chloride ion in a fallow structured soil
Authors: Nicholls Peter H. , Bromilow Richard H. , Addiscott Thomas M.
Published: November 2006

The distribution with depth of fluometuron, aldoxycarb and chloride anion was measured in the field during winter in a well‐structured fallow soil. Distribution patterns measured at monthly intervals over 4 months were compared with those simulated by two different models: that of Leistra, which is representative of models using Darcy's Law to describe water movement in soil; and a modified version of that originally developed by Addiscott to describe nitrate movement, which uses the concept of mobile and immobile water categories. Both models correctly predicted the general pattern of movement but underestimated the movement of chloride ion whilst overestimating the movement of aldoxycarb and fluometuron after the first month. The model of Addiscott was encouragingly accurate in predicting the small quantities of fluometuron which penetrated to depths between 25 and 40 cm.
Distribution and likely effectiveness of spray deposits within a cotton canopy from fine ultralow‐volume spray applied by aircraft
Authors: Uk Solang , Courshee Richard J.
Published: November 2006

In a study to evaluate the deposit distribution from aerial sprays on cotton in the Sudan Gezira, a combination of subjective visual assessment and quantitative chemical analysis was used. Spray deposits on leaf discs, made visible in ultraviolet light by the addition of a fluorescent pigment, were subjectively grouped into classes according to a series of standards. The mean chemical deposit on the discs in each class was measured by the gas‐liquid chromatographic determination of the profenofos content. The 810 leaves needed to define the deposit distribution with good confidence could be examined economically within the required period by this combination of quick subjective assessment and subsequent quantitative chemical calibration. Results showed that the vertical profile of the deposit distribution within the canopy followed the classical exponential decay curve. The rate of decrease depended mainly on the foliage density. The foliage effectively dampened the wind turbulence so much that the penetration of visible droplets within the lower two‐thirds of the canopy was predominantly by gravity. Suggestions for the use of the deposit distribution probability to predict the likely biological effectiveness in the field are discussed.
Residues of glyphosate in irrigation water
Authors: Bowmer Kathleen H.
Published: November 2006

In investigations to determine the extent of contamination from typical spray applications of glyphosate, a conservative fluorescent tracer was used to predict the theoretical upper limit in channels carying flowing water. Polarographic and bioassay estimations of glyphosate showed reasonable correlation with these predictions for samples collected immediately downstream of the spray zone. The current desirable criteria of 0.1 g m−3 for drinking water in Australia, and 0.2 g m−3 approved for irrigation in the United Kingdom would be exceeded, except in sprayed channels of highest cross‐sectional area. Only about 7–17% of the glyphosate applied entered the water when a foam spray was routinely directed with a hand‐gun on to a marginal growth of Paspalum paspalodes (Michx.) Scribn., and it was calculated that this technique could reduce concentrations in the spray zone to less than 0.1 g m−3 in many situations. Tributary dilution, dispersion, and adsorption processes also attenuate the contamination downstream. The impact of dispersion processes on dissipation of the glyphosate concentration was relatively small, but the glyphosate concentration was reduced by 63% as a result of adsorption during transport downstream through 2 km of drainage channel containing deep silty sediments.
Conversion of four carbamoyloximes in soil samples from above and below the soil water table
Authors: Smelt Johan H. , Dekker Abraham , Leistra Minze , Houx Norbert W. H.
Published: November 2006

2‐Methyl‐2‐(methylsulphinyl)propionaldehyde O‐methylcarbamoyloxime (aldicarb sulphoxide), aldoxycarb, oxamyl and methomyl were incubated at 10°C in soil samples taken from layers above and below shallow ground‐water tables at four locations in the Netherlands. Soil samples from above the water table were incubated under moist and aerobic conditions. The anaerobic conditions below the water table were simulated by incubating the soil samples under 0.5‐1 cm of ground water, and a nitrogen atmosphere. During incubation, the pH and redox potentials were measured. Less than 5% of the oxamyl and methomyl remained after one day in four water‐saturated, anaerobic subsoils. The half‐lives of aldicarb sulphoxide and aldoxycarb ranged from 5.1 to 131 days in the four anaerobic subsoils. Conversion rates in the aerobic soil layers above the water table were from 8 to more than 100 times lower than in the water‐saturated layers in the same soil profile. Half‐lives in the aerobic soils ranged from 26 days for oxamyl in loamy fine sand (pH 8.0), to 1100 days for aldoxycarb in fine sand (pH 5.0). When soil from below the water table was incubated aerobically, the conversion rates of oxamyl and aldoxycarb were drastically reduced. The opposite was found when an originally aerobic soil was incubated anaerobically. Autoclaving the incubation systems retarded the conversions.
Novel chemical approaches to crop protection: Needs and solutions
Authors: Graham‐Bryce Ian J.
Published: November 2006

The examination of conventional chemical methods of crop protection suggests problems and opportunities that call for alternative approaches. The need for such novel treatments is considered in relation to damaging organisms not controlled by traditional pesticides, biological availability, resistance, selectivity and compatibility with other methods within the concept of integrated pest, disease or weed management. Analysis of these needs and opportunities suggests directions in which to seek novel chemical agents including those which can attack vital processes not previously exploited as target sites, the modification of physicochemical properties determining mobility and availability, chemical formulation, symptom suppression and the manipulation of chemically‐mediated processes other than direct toxic action, and the use of agents which extend the usefulness of existing toxic agents. Examples illustrating these approaches are discussed.
Organophosphorothioates and synergised synthetic pyrethroids as grain protectants on bulk wheat
Authors: Bengston Mervyn , Davies Richard A. H. , Desmarchelier James M. , Henning Ronald , Murray William , Simpson Bruce W. , Snelson Jack T. , Sticka Rex , Wallbank Barry E.
Published: November 2006

Organophosphorothioates and synergised synthetic pyrethroids were used in duplicate field trials carried out on bulk wheat in commercial silos in Queensland and New South Wales. Laboratory bioassays using malathion‐resistant strains of insects were carried out on samples of treated grain at intervals over 9 months. These established that all treatments were generally effective. Deltamethrin (2 mg kg−1)+ piperonyl butoxide (8 mg kg−1), fenitrothion (12 mg kg−1)+ fenvalerate (1 mg kg−1)+ piperonyl butoxide (8 mg kg−1), fenitrothion (12 mg kg−1)+ phenothrin (2 mg kg−1)+ piperonyl butoxide (8 mg kg−1) and pirimiphos‐methyl (4 mg kg−1)+ permethrin (1 mg kg−1)+ piperonyl butoxide (8 mg kg−1) controlled common field strains of Sitophilus oryzae (L.) and Rhyzopertha dominica (F.). Against a highly resistant strain of S. oryzae, deltamethrin (2 mg kg−1)+ piperonyl butoxide (8 mg kg−1) was superior to the remaining treatments. All treatment combinations completely prevented progeny production in Tribolium castaneum (Herbst), T. confusum Jacquelin du Val and in Ephestia cautella (Walker).

Residues of deltamethrin, fenvalerate, permethrin and phenothrin were determined and shown to be highly persistent on stored wheat. During milling, residues accumulated in the bran fractions and were reduced in white flour. They were not significantly reduced during baking.
The distribution of aldicarb and its metabolites between Lumbricus terrestris, water and soil
Authors: Briggs Geoffrey G. , Lord Kenneth A.
Published: November 2006

Aldicarb is taken up by earthworms from aqueous solution to give concentrations in the worms comparable to that in the external aqueous solutions. Uptake from waterlogged soils is similar, but much less aldicarb is taken up from drier soils. Aldicarb sulphoxide [2‐methyl‐2‐(methylsulphinylpropionaldehyde O‐methylcar‐bamoyloxime], aldoxycarb and oxamyl are poorly taken up, giving concentrations in the worm of about 5% of the external aqueous concentration. In worms, aldicarb is rapidly converted to the sulphoxide which has a half‐life in worms of 19 h at 15°C, and 50 h at 5°C.
Effect of spraying techniques on the brown rot of peach fruit, and on black spot, powdery mildew and the two‐spotted mite of apple trees
Authors: Whan James H. , Smith Ian R. , Morgan Norman G.
Published: November 2006

Application by hand‐held equipment of the commercially recommended doses of proprietary formulations of captan (9.0 g a. i. per tree), mancozeb (10.8 g a. i. per tree), oxythioquinox (1.1 g a. i. per tree), and cyhexatin (1.8 g a. i. per tree), in spray volumes ranging from 0.225 to 9.0 litres per tree, gave commercial control of the brown rot of peach fruit, and of black spot (apple scab), powdery mildew and the two‐spotted mite (Tetranychus urticae) of apple trees. Commercial control was also obtained using a quarter of the recommended doses when applied in 0.225 or 2.25 litres per tree.

The residue of oxythioquinox on the leaves, immediately after applying 1.1 g a. i. per tree, doubled as the volume of spray was reduced from 9.0 to 2.25 litres per tree, and increased further when the volume was reduced to 0.225 litres per tree. It is suggested that some of the oxythioquinox ran off the trees at the higher volumes, and that less run‐off at lower volumes resulted in higher chemical residues.
Resistance to fungicides which inhibit ergosterol biosynthesis in laboratory strains of Botrytis cinerea and Ustilago maydis
Authors: Leroux Pierre , Gredt Michel
Published: November 2006

The strains of Botrytis cinerea or Ustilago maydis selected on fenarimol, triarimol, or triadimefon were also resistant to the other inhibitors of sterol C‐14 demethylation; the sterol composition of the strains was normal. Among the isolates of U. maydis resistant to dodemorph, fenpropidin, fenpropimorph and tridemorph, some were resistant to the 15‐azasteroid A 25822B and did not contain ergosterol. The other strains remained sensitive to A 25822B and had a normal sterol composition. All the resistant isolates and the wild‐type were inhibited to the same extent by nystatin and pimaricin.
Effect of fenpropimorph and imazalil on sterol biosynthesis in penicillium italicum
Authors: Kerkenaar Antonius , Van Rossum Johanna M. , Versluis Gerritje G. , Marsman Jan W.
Published: November 2006

Fenpropimorph was found to be highly active against Penicillium italicum (EC50 0.01/μg ml−1). Conidia of P. italicum, treated with low concentrations of fenpropimorph, swelled in size and showed distorted germ tubes. During the initial stages of mycelial growth, fenpropimorph had little or no effect on the dry weight increase, which became strongly inhibited within 24 h after addition of the toxicant (0.05, 0.1 and 0.2 μg ml−1). Irregular deposition of β–1,3 and β–1, 4 polysaccharides, probably chitin, was observed after treatment with fenpropimorph or imazalil. Fenpropimorph (0.05 and 0.2 μ ml−1) caused the accumulation of a major demethyl‐sterol that was different from ergosterol. It was identified as ergosta‐8, 14, 24(28)‐trien‐3β‐ol by mass, infrared, ultraviolet and proton nuclear magnetic resonance, spectrometric procedures. At both concentrations, the accumulation was already detected after incubation for 2 h. In contrast, imazalil (0.1 μg ml−1) caused the accumulation of several methyl‐ and dimethyl‐sterols which were tentatively identified as eburicol (24‐methylene‐24, 25‐dihydrolanosterol), 4, 14α‐dimethylergosta‐8, 24(28)‐dien‐3‐one, 14α‐methylergosta‐8, 24(28)‐dien‐3‐one and obtusifoliol (4, 14α‐dimethylergosta‐8, 24(28)‐dien‐3α‐ol). The accumulation of ergosta‐8, 14,24(28)‐trien‐3β‐ol indicates inhibition of the Δ14‐reductase in P. italicum in a similar manner to that found previously in Ustilago maydis.
The effect of temperature on the activity and metabolism of glyphosate applied to rhizome fragments of elymus repens (=Agropyron repens)
Authors: Coupland David
Published: November 2006

The effect of temperature on the activity and metabolism of glyphosate, as its mono(isopropylammonium) salt, in single‐node rhizome fragments of Elymus repens was investigated in controlled environment cabinets. Post‐treatment temperatures of 26/16° (day/night) reduced the activity of the herbicide compared with that at 10/6°, respectively. Under both temperature regimes and using [14C]glyphosatemono(isopropylammonium), more [14C]glyphosate accumulated in the node tissues and buds than in the internodes, but at teh higher temperature the rate of glyphosate metabolism was greater, and more 14C was lost as [14C]carbon dioxide. Evidence is presented to indicate that plant extracts contained at least two components which yielded glyphosate and aminomethylphosphonic acid after both acid or base treatment, but not on incubation with β‐glucosidase. It is therefore tentatively suggested that these metabolites are not β‐glycosides but perhaps are conjugates with other natural plant constituents involving the phosphonyl and/or amino groups of the herbicide.
Effect of some ergosterol biosynthesis inhibiting fungicides on sterols and cytochrome P‐450 from the Japanese quail Coturnix coturnix
Authors: Rivière Jean‐Louis , Leroux Pierre , Bach Jocelyne , Gredt Michel
Published: November 2006

Nine fungicides that inhibit ergosterol biosynthesis (diclobutrazol, fenarimol, fenpropimorph, imazalil, nuarimol, prochloraz, propiconazole, triadimefon, triadimenol) and one plant growth regulator (ancymidol) were administered to Japanese quails (Coturnix coturnix). Most of these compounds had a moderate or no effect, but prochloraz, imazalil and, to a lesser extent, propiconazole were shown to produce a dramatic increase in liver weight and cytochrome P‐450 level. These three compounds were also found to be potent in‐vitro inhibitors of 7‐ethoxycoumarin O‐de‐ethylase and aniline hydroxylase, thus resulting in a biphasic effect on drug‐metabolising enzymes. With these three compounds, and some others, an accumulation of lanosterol in liver was also observed, suggesting an inhibition of sterol synthesis.
Erratum: Multipoint competition, strategic similarity and entry into geographic markets L. Fuentelsaz, J. Gómez. Strategic Management Journal, 2006; 27; 477–499
Authors: Fuentelsaz L. , Gómez J.
Published: October 2006

The original article to which this Erratum refers was published in Strategic Management Journal Vol. 27, No. 5, pp 477–499, 2006. DOI: 10.1002/smj.529

A paragraph in Spanish on page 481 of the Strategic Management Journal Vol. 27, No. 5, pp 477‐499, 2006, DOI: 10.1002/smj529 was incorrectly included. The publisher apologises for this error.
The First Complex of Benzilbis(thiosemicarbazone) acting as Bridging Ligand only through the Sulfur Atom
Authors: López‐Torres Elena , Calatayud David G. , Mendiola Antonia , Pastor César J. , Procopio Jésus R.
Published: November 2006

The first complex with benzilbis(thiosemicarbazone) LH6 acting only as a bridge between two metallic centres through the sulfur atoms, was obtained from the reaction with methylmercury chloride. This complex shows a 1:2 ligand : mercury ratio and has been spectroscopically characterized and recrystallized in toluene. The ligand acts as a dianion, with an intermediate situation between cis and trans dispositions, and it is bonded to both methylmercury moieties through the sulfur atoms, giving a binuclear complex with linear CS coordination for the mercury atoms.
Complexation of Alkali Triflates by Crown Ethers: Synthesis and Crystal Structure of [Na(12‐crown‐4)2][SO3CF3], [Na(15‐crown‐5)][SO3CF3], [Rb(18‐crown‐6)][SO3CF3], and [Cs(18‐crown‐6)][SO3CF3]
Authors: Gjikaj Mimoza , Adam Arnold
Published: November 2006

Complexes of trifluoromethanesulfonates (triflates) with alkali metals Na, Rb, Cs have been prepared in the presence of various macrocyclic polyether crowns [(12‐crown‐4), (15‐crown‐5) and (18‐crown‐6)]. Depending on the combination of alkali ion with crown, the complexes include separated ion pairs [Na(12‐crown‐4)2] [SO3CF3] (1) and contact ion pairs [Na(15‐crown‐5)] [SO3CF3] (2), [Rb(18‐crown‐6)] [SO3CF3] (3), and [Cs(18‐crown‐6)] [SO3CF3] (4), in which the triflate acts as a bidentate ligand. It is shown that the choice of crown ether is of paramount importance in determining the solid‐state structural outcome. The complex resulting from the pairing of crown ether (1) develops, when the crown ether is too small in relation to the alkali ion radius. When the cavity size of the crown ether is matched with the alkali ion radius, simple monomeric structures are identified in 2, 3 and 4.

The title compounds crystallize in the monoclinic crystal system: 1: space group P2/c with a = 9.942(3), b = 11.014(2), c = 10.801(3) Å, β = 97.30(2)°, V = 1173.1(4) Å3, Z = 2, R1 = 0.0812, wR2 = 0.1133: 2: space group P21/m with a = 7.949(2), b = 12.063(3), c = 9.094(2) Å, β = 105.98(2)°, V = 838.3(4) Å3, Z = 2, R1 = 0.0869, wR2 = 0.1035: 3: space group P21/c with a = 12.847(5), b = 8.448(2), c = 22.272(6) Å, β = 122.90(3)°, V = 2029.5(1) Å3, Z = 4, R1 = 0.0684, wR2 = 0.1044: 4: space group P21/n with a = 12.871(3), b = 8.359(1), c = 19.019(4) Å, β = 92.61(2)°, V = 2044.2(6) Å3, Z = 4, R1 = 0.0621, wR2 = 0.0979.
Zur Elektronenstruktur metallorganischer Komplexe der f‐Elemente. 64 Äußert sich die zwitterionische Natur des Triphenylphosphanoxid‐Liganden auch in seinen spektrochemischen Eigenschaften?
Authors: Amberger Hanns‐Dieter , Zhang Lixin , Reddmann Hauke , Apostolidis Christos , Walter Olaf
Published: November 2006

Electronic Structures of Organometallic Compounds of f Elements. 64 Does the Zwitterionic Nature of the Triphenylphosphine Oxide Ligand Manifest itself in its Spectrochemical Properties?

The triphenylphosphine oxide mono adducts of the moiety tris(η5‐cyclopentadienyl)lanthanide(III) (Ln(Cp)3; Ln = Pr (1), La (2)) were synthesized and structurally characterized. The Ln–O distances of these compounds are noticeably shorter than those of the corresponding THF adducts. A crystal field (CF) analysis of the optical spectra of 1 leads to a low absolute value of the quadratic CF parameter which is comparable with those of [Pr(Cp)3(L)]− adducts with anionic bases but not with [Pr(Cp)3(MeTHF)]. Reasons for the latter finding are presented.
Synthesis, Structures, and Properties of Layered Quaternary Chalcogenides of the General Formula ALnEQ4 (A = K, Rb; Ln = Ce, Pr, Eu; E = Si, Ge; Q = S, Se)
Authors: Choudhury Amitava , Polyakova Larisa A. , Hartenbach Ingo , Schleid Thomas , Dorhout Peter K.
Published: November 2006

Four related quaternary compounds containing rare‐earth metals have been synthesized employing the molten flux method and metathesis. The reactions of Eu and Rb2S5 with Si and Ge in evacuated fused silica ampoules at 725 °C for 150 h yielded RbEuSiS4 (I) and RbEuGeS4 (II), respectively. On the other hand, a reaction between CeCl3 and K4Ge4Se10 at 650 °C for 148 h has yielded KCeGeSe4 (III) and KPrSiSe4(IV) was obtained by the reaction of elemental Pr, Si and Se in KCl flux at 850 °C for 168 h. Crystal data for these compounds are as follows: I, orthorhombic, space group P212121 (#19), a = 6.392(1), b = 6.634(2), c = 17.001(3) Å, α = β = γ = 90°, Z = 4; II, monoclinic, space group P21/m (#11), a = 6.498(2), b = 6.689(3), c = 8.964(3) Å, β = 108.647(6)°, Z = 2; III, monoclinic, space group P21 (#4), a = 6.852(2), b = 7.025(2), c = 9.017(3) Å, β = 108.116(2)°, Z = 2; IV, monoclinic, space group P21 (#4), a = 6.736(2), b = 6.943(2), c = 8.990(1) Å, β = 108.262(2)°, Z = 2. The crystal structures of I‐IV contain two‐dimensional corrugated anionic layers of the general formula, [LnEQ4]− (Ln = Ce, Pr, Eu; E = Si, Ge and Q = S, Se) alternately piled upon layers of alkali cations. In addition to structural elucidation, Raman and UV‐visible spectroscopy, and magnetic measurements for compound III (KCeGeSe4) are also discussed.
Relationship between dietary supply of long‐chain fatty acids and membrane composition of long‐ and very long chain essential fatty acids in developing rat photoreceptors
Authors: Suh M. , Wierzbicki A. A. , Lien E. , Clandinin M. T.
Published: November 2006

The present study was designed to determine if dietary supply of long‐chain fatty acid (LCFA, C20∶4n‐6, and/or C22∶6n‐3), reflecting levels that might be incorporated into infant formulas, influences the fatty acid composition of the visual cell membrane. The rod outer segment (ROS) of the retina was analyzed from rats fed diets varying in the ratio of 18∶2n‐6 to 18∶3n‐3 with or without 20∶4n‐6 [arachidonic acid (AA)] and 22∶6n‐3 (docosahexaenoic acid) from birth to six weeks of age. The level of very long chain fatty acids (VLCFA, C24−C36) was identified using gas chromatography and gas chromatography‐mass spectrometry. In the ROS, the highest relative percent of AA was attained in phosphatidylcholine (PC) and phosphatidylethanolamine (PE) of animals fed 1% AA diet, whereas feeding 0.7% docosahexaenoic acid (DHA) diet significantly increased the DHA level in PC, phosphatidylserine, and phosphatidylinositol compared to feeding diets containing AA. VLCFA of n‐6 and n‐3 up to C36 were found in PC, with the most abundant fatty acids being C32 and C34. In PC, phosphatidylserine and PE, the n‐6 tetraenoic VLCFA level was highly increased in animals fed 1% AA compared to other dietary groups. This study suggests that dietary fat containing small amounts of AA or DHA is an important factor influencing membrane fatty acid composition of the visual cell during development.
Is dietary docosahexaenoic acid essential for term infants?
Authors: Makrides Maria , Neumann Mark A. , Gibson Robert A.
Published: November 2006

There is a need to determine whether there is a dietary requirement for docosahexaenoic acid (DHA, 22∶6ω3) by term infants to achieve their full developmental potential. Studies of brain fatty acid composition have demonstrated that infants who were breast fed have greater levels of cerebral cortex DHA than infants who were formula fed, suggesting that DHA in the cerebrum is dependent on a supply in the diet. Some physiological studies report that electrophysiological and behavioral assessments of visual function are improved in breast‐fed infants relative to those fed formula, and that this is related to the level of DHA in their erythrocytes, whereas other studies demonstrate equivalent visual function between breast‐and formula‐fed infants. However, randomized studies of DHA supplementation of infant formula demonstrate that the visual function of formula‐fed infants can be improved to breast‐fed levels by adding DHA to formula. Further work is necessary to establish if there are long‐term benefits of dietary DHA to the term infant.
Bisallylic hydroxylation and epoxidation of polyunsaturated fatty acids by cytochrome P450
Authors: Oliw Ernst H. , Bylund Johan , Herman Ceil
Published: November 2006

Polyunsaturated fatty acids can be oxygenated by cytochrome P450 to hydroxy and epoxy fatty acids. Two major classes of hydroxy fatty acids are formed by hydroxylation of the ω‐side chain and by hydroxylation of bisallylic methylene carbons. Bisallylic cytochrome P450‐hydroxylases transform linoleic acid to 11‐hydroxylinoleic acid, arachidonic acid to 13‐hydroxyeicosa‐5Z,8Z,11Z,14Z‐tetraenoic acid, 10‐hydroxyeicosa‐5Z,8Z,11Z,14Z‐tetraenoic acid and 7‐hydroxyeicosa‐5Z,8Z,11Z,14Z‐tetraenoic acid and eicosapentaenoic acid to 16‐hydroxyeicosa‐5Z,8Z,11Z,14Z,17Z‐pentaenoic acid, 13‐hydroxyeicosa‐5Z,8Z,11Z,14Z,17Z‐pentaenoic acid and 10‐hydroxyeicosa‐5Z,8Z,11Z,14Z,17Z‐pentaenoic acid as major metabolites. The bisallylic hydroxy fatty acids are chemically unstable and decompose rapidly tocis‐trans conjugated hydroxy fatty acids during acidic extractive isolation. Bisallylic hydroxylase activity appears to be augmented in microsomes induced by the synthetic glucocorticoid dexamethasone and by some other agents, but the P450 gene families of these hydroxylases have yet to be determined. The fatty acid epoxides, which are formed by cytochrome P450, are chemically stable, but are hydrolyzed to diols by soluble epoxide hydrolases. Epoxidation of polyunsaturated fatty acids is a prominent pathway of metabolism int he liver and the renal cortex and epoxygenase activity appears to be under homeostatic control in the kidney. Many arachidonate epoxygenases have been identified belonging to the CYP2C gene subfamily. Epoxygenases have also been found in the central nervous system, endocrine organs, the heart and endothelial cells. Epoxides of arachidonic acid have been found to exert pharmacological effects on many cells.
Anin vivo13C magnetic resonance spectroscopic study of the relationship between diet and adipose tissue composition
Authors: Thomas E. L. , Frost G. , Barnard M. L. , Bryant D. J. , Taylor‐Robinson S. D. , Simbrunner J. , Coutts G. A. , Burl M. , Bloom S. R. , Sales K. D. , Bell J. D.
Published: November 2006

13C magnetic resonance spectroscopy (MRS) is a noninvasive technique used in the study of lipids. We applied13C MRS to assess the effects of long‐term dietary variation on adipose tissue composition in humans.In vivo13C MRS was used to analyze the fatty acid composition of adipose tissue in 88 healthy volunteers with significantly different diets (38 vegans, 11 vegetarians, and 39 omnivores) assessed by analysis of dietary records. Results were compared with the serum lipid profile.13C MRS revealed clear differences in the adipose tissue composition of vegans, which contained more unsaturated (P<0.01) and fewer saturated fatty acids (P<0.01) compared with omnivores and vegetarians. The vegan subjects had a significantly lower intake of saturated fatty acids and higher intake of polyunsaturated fatty acids than either the omnivore or the vegetarian groups (P<0.01). These findings were associated with significantly lower levels of serum total cholesterol and low density lipoprotein‐cholesterol in the vegan group compared with the omnivores. Our results demonstrate the use of13C MRS for the noninvasive study of adipose tissue composition and its application to the study of the interaction between long‐term dietary and metabolic risk factors in humans.
Effects of clofibrate on lipids and fatty acids of mouse liver
Authors: Pennacchiotti G. L. , Rotstein N. P. , Aveldaño M. I.
Published: November 2006

Clofibrate administration significantly altered the amount and fatty acid composition of lipids in mouse liver. The net content of phospholipids (PL) increased and that of triacylglycerols (TG) decreased concomitantly with liver enlargement in mice treated for two weeks with this drug (0.5% w/w in the food). The highest increase among PL was in phosphatidylcholine; other components either showed lower increases or, as in the case of sphingomyelin and the plasmalogens, decreased. In all lipid classes the treatment resulted in altered ratios between major saturates, between saturates and monoenes, and between major polyenes. Among these, 20∶3n–6 and 22∶5n–3 increased several‐fold, and the 20∶3n–6/20∶4n–6 and 22∶5n–3/22∶6n–3 ratios increased due to a more active formation of the precursors than of the corresponding products. This change affected all glycerolipid classes. Liver sphingomyelin showed a relative enrichment in monoenoic fatty acids like 22∶1 and 24∶1, caused by a net decrease in the amount of saturates, particularly 22∶0 and 24∶0. The stimulated membrane proliferation imposed by clofibrate must increase phospholipid synthesis and, hence, the need for fatty acids. The results suggest that these demands are met mostly by TG acyl groups, either directly or after oxidation/desaturation processes. This was apparently the case for the polyenoic fatty acids of the n‐6 and n‐3 series. The longer chain (C22 and C24) components decreased, suggesting that their oxidation was stimulated to provide part of the required (C20 and C22) polyenes.
A simple method for the synthesis of ceramides and radiolabeled analogues
Authors: Anand Jasbir K. , Sadozai Khalid K. , Hakomori Sen‐itiroh
Published: November 2006

A simple method has been developed for the coupling of amines to carboxylic acids.N‐Fatty‐acyl‐sphingosine, cerebroside, and GM3, as well as their respective [14C] analogues, were synthesized using diethylphosphoryl cyanide as a potent coupling agent in the presence of triethylamine. The reaction procedure is rapid, racemization‐free, and utilizes acids without derivatization. The desired ceramide products were obtained in 85–90% yield within one hour. The facile method presented here can also be used to synthesize [3H]‐N‐acyl‐labeled, as well as [14C] [3H] double‐labeled, ceramides.
Dietary eritadenine‐induced alteration of molecular species composition of phospholipids in rats
Authors: Sugiyama Kimio , Yamakawa Akihiro
Published: November 2006

The effect of dietary eritadenine, a hypocholesterolemic compound found in the mushroomLentinus edodes, on the fatty acid and molecular species profiles of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) in the plasma and liver microsomes was investigated in relation to the hypocholesterolemic action of the compound in rats. Animals were fed the control or eritadenine‐supplemented (50 mg/kg diet) diet for 14 d. Eritadenine supplementation significantly decreased the plasma concentrations of cholesterol and phospholipids, but not triglycerides. The PC/PE ratio of liver microsomes, but not plasma, was also markedly decreased by eritadenine. Eritadenine supplementation was found to increase the proportion of 18:2n‐6 and, inversely, to decrease the proportion of 20:4n‐6 and 22:5n‐6 in plasma PC and liver microsomal PC and PE, indicating that eritadenine depressed the metabolism of linoleic acid. The effect of eritadenine on the profile of n‐3 fatty acids was dissimilar in PC and PE. These changes in fatty acid composition were selectively reflected in the molecular species composition of both PC and PE; the extent of increase in 16:0–18:2 molecular species or decrease in 18:0–20:4 molecular species was apparently greater than that of other molecular species containing 18:2 or 20:4 in the sn‐2 position. These results suggest that, in addition to the decrease in liver microsomal PC/PE ratio, the alteration of plasma PC molecular species composition might also participate in the hypocholesterolemic action of eritadenine.
cis/trans isomerization of unsaturated fatty acids as possible control mechanism of membrane fluidity inPseudomonas putida P8
Authors: Loffeld Burkhard , Keweloh Heribert
Published: November 2006

Exponentially growing cells ofPseudomonas putida had an increased ratio of saturated to unsaturated fatty acids in response to increased growth temperatures. Resting cells in which fatty acid biosynthesis was stopped reacted to a thermal increase by convertingcis‐monounsaturated fatty acids totrans isomers.cis/trans isomerization of up to 60% of the unsaturated fatty acids was also activated by alcohols of different chain length. Their effective concentrations apparently depended on the lipophilic character of the alcohols. Also, a salt shock caused by the addition of NaCl resulted in the production oftrans fatty acids. However, cells that were adapted to growth media of high osmolarity synthesized cyclopropane fatty acids instead oftrans fatty acids. Activity ofcis/trans‐isomerase was dependent on the growth phase and was significantly higher during logarithmic growth than during the stationary phase. The results of this study agree with the hypothesis that the isomerization ofcis intotrans unsaturated fatty acids is an emergency action of cells ofP. putida to adapt membrane fluidity to drastic changes of environmental conditions.
Production of 3R‐hydroxy‐polyenoic fatty acids by the yeast Dipodascopsis uninucleata
Authors: Venter P. , Kock J. L. F. , Kumar G. Sravan , Botha A. , Coetzee D. J. , Botes P. J. , Bhatt R. K. , Falck J. R. , Schewe T. , Nigam S.
Published: November 2006

Various fatty acids were fed to the yeast Dipodascopsis uninucleata UOFS Y 128, and the extracted samples were analyzed for the accumulation of 3‐hydroxy metabolites with the help of electron impact gas chromatography‐mass spectrometry. Fatty acids containing a 5Z,8Z‐diene system (5Z,8Z,11Z‐eicosatrienoic, 5Z,8Z,11Z,14Z‐eicosatetraenoic, and 5Z,8Z,11Z,14Z,17Z‐eicosapentaenoic acids) yielded the corresponding 3‐hydroxy‐all‐Z‐eicosapolyenoic acids. Moreover, linoleic acid (9Z,12Z‐octadecadienoic acid) and 11Z,14Z,17Z‐eicosatrienoic acid were converted to the 3‐hydroxylated metabolites of shorter chain length, e.g., 3‐hydroxy‐5Z,8Z‐tetradecadienoic acid and 3‐hydroxy‐5Z,8Z,11Z‐tetradecatrienoic acid, respectively. In contrast, no accumulation of a 3‐hydroxy metabolite was observed with oleic acid (9Z‐octadecenoic acid), linolelaidic acid (9E,12E‐octadecadienoic acid), γ‐linolenic acid (6Z,9Z,12Z‐octadecatrienoic acid), and eicosanoic acid as substrate. These findings pinpoint that the 3‐hydroxylation of a fatty acid in Dipodascopsis uninucleata requires a 5Z,8Z‐diene system either directly or following initial incomplete β‐oxidation. Following analysis of the enantiomer composition, the arachidonic acid metabolite was identified as 3R‐hydroxy‐5Z,8Z,11Z,14Z‐eicosatetraenoic acid, which rules out a normal β‐oxidation as biosynthetic route to this new class of oxylipins.
Recent developments in the field of plant steroid hormones
Authors: McMorris Trevor C.
Published: November 2006

Brassinolide and related brassinosteroids are a novel group of steroids which appear to be ubiquitous in plants. There is compelling evidence, particularly from recent genetic studies, that these steroids are essential for normal plant growth and development. Synthesis of brassinosteroids and aspects of their biochemistry are reviewed.
Situating alcohol use and delinquency within developmental and societal context: The case of Korean youth
Authors: Lee Ji‐Min , Bell Nancy J. , Watson Wendy
Published: November 2006

In this study involving self‐report questionnaire data from 955 tenth‐grade students in three locations within Korea, we address the meanings of alcohol use and delinquency for Korean youth. Findings (a) supported a facilitative role for alcohol, but not delinquency, with respect to perceived peer social competence; (b) indicated negative associations of both alcohol use and delinquency with parental relations, valuing academic achievement, and collectivistic values, and positive associations with friends’ risk behaviours; (c) showed no relationship of these behaviours with self‐esteem, coping, parental permissiveness or individualistic values; and (d) revealed that perceived benefits of alcohol use and delinquency include not only social facilitation but also exploration and assertion of independence, suggesting a potential connection, as in Western societies, between risk taking, and identity exploration.
Etiology, Diagnosis, and Management of Vaginitis
Authors: Mashburn Jane
Published: November 2006

Women often seek medical care for vaginal complaints. Many times, the cause of the complaint is misdiagnosed by the woman and/or her provider. These vaginal complaints may be related to infections, which when misdiagnosed or mistreated, can lead to more severe problems. This article describes the three most common vaginal infections, bacterial vaginosis, trichomoniasis, and vulvovaginal candidiasis. Appropriate diagnostic techniques and management therapies are reviewed.
Responses of developmental yield formation processes in oats to variety, nitrogen, seed rate and plant growth regulator and their relationship to quality
Authors: BROWNE R. A. , WHITE E. M. , BURKE J. I.
Published: November 2006

Outcomes of developmental yield formation processes in oats, namely number of panicles/m2, number of grains/panicle, mean grain weight and incidences of aborted and tertiary grains, were measured in a series of experiments in Northern Ireland and the Republic of Ireland in 1997/98 and 1998/99. Seed rate (200 and 300 seeds/m2), nitrogen (0–200 kg/ha) and plant growth regulator (chlormequat chloride) treatments were applied to the spring oat varieties Aberglen and Barra in one spring- and two autumn-sown experiments, and to the winter varieties Gerald and Image in one autumn-sown experiment. Large variation in number of panicles/m2 and grains/panicle was observed between the experiments and varieties and in response to seed rate, with number of grains/panicle generally being inversely related to number of panicles/m2. At the higher rates of nitrogen rate both number of panicles/m2 and grains per panicle increased. Mean grain weights were relatively constant and were largely determined by variety. Chlormequat chloride had relatively little effect on the yield components, the most consistent being small reductions in mean grain weight.

Tertiary grains occurred rarely in the varieties and agronomic treatments used in the programme but were more frequent at higher rates of nitrogen in most of the experiments. Numbers of aborted grains were usually higher where grain numbers were higher although the effects of variety, seed rate and nitrogen on aborted grains were not consistent. Structure of the grain population, i.e. the relative proportions of primary and secondary grain, was stable despite the large differences in number of panicles/m2, spikelet numbers and mean grain weight.

The greater yield and growth enhancing effects of nitrogen compared with seed rate and plant growth regulator were apparent in responses by developmental processes active later in the life cycle, namely production of tertiary grains and grain filling.

Wide variation in number of panicles/m2 (c. 200–450) and number of grains/panicle (c. 55–145) produced in the crops grown under a very full expression of agro-ecological conditions in this programme was accompanied by small variation in mean grain weight (c. 38–47 mg/primary grain and c. 22–29 mg/secondary grain) and in numbers of tertiary (<2/panicle) and aborted grains (<10/panicle). Plasticity of development throughout the life cycle, manifested both as the established yield components and in numbers of tertiary and aborted grains, was largely effective in ensuring stability of mean grain weight and quality in oats.