Mark Feldlaufer - Academia.edu (original) (raw)

Papers by Mark Feldlaufer

Rearing Animal and Plant Pathogen Vectors, 2014

ChemInform, 2010

ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Apidologie, 1999

The tau-fluvalinate content of 13 lot numbers of Apistan® strips was determined by high perfo... more The tau-fluvalinate content of 13 lot numbers of Apistan® strips was determined by high performance liquid chromatography (HPLC). The average percent tau-fluvalinate in strips from each lot number ranged from 9.95 to 10.64 %, which falls within the range specified in the Confidential Statement of Formula (CSF) on file with the Environmental Protection Agency. It is not likely that the reduced efficacy in parasitic mite (Varroa jacobsoni) control reported in certain areas of the US is due to the tau-fluvalinate content of Apistan® strips. © Inra/DIB/AGIB/Elsevier, Paris tau-fluvalinate content / Apistan® / liquid chromatography / Apistan® resistance

The brown marmorated stink bug, Halyomorpha halys (Stal) (Hemiptera: Pentatomidae), is an extreme... more The brown marmorated stink bug, Halyomorpha halys (Stal) (Hemiptera: Pentatomidae), is an extremely polyphagous pest in Asia and host rang includes plants of economic importance such as pea, soybean, apple, peach, cherry, and various other fruit and ornamental trees. Damage to crops from H halys in mid-Atlantic States has reached critical levels, especially, caused serious damage to peach and apple crops with some growers loosing over 60 to 100 percent of their crop. The effectiveness of various insecticide classes to control of H. halys has been tested in laboratory conditions, however, some pesticide application must be conducted by a pest control applicator. There is no current effective biological control agent available, thus alternative management tools are needed to protect plants. Feeding deterrents/repellents of H. halys have been identified in the laboratory bioassay and can be immediately used in orchards or other commodity-based fields. Because they are natural products,...

Lipids, 1993

ABSTRACT Cactus bees are important pollinators that contribute to the long-term stability of arid... more ABSTRACT Cactus bees are important pollinators that contribute to the long-term stability of arid regions in the United States. Since all insects are dependent upon a dietary source of sterol for normal growth, development and reproduction, a study was undertaken to determine neutral sterols available to cactus bees. The total neutral sterol composition of hand-collected pollen was determined for three species of Sonoran cacti by gas-liquid chromatography and mass spectrometry. 24-Methylenecholesterol was the predominant pollen sterol in Engelmann's prickly pear,Opuntia phaeacantha, cholla,O. versicolor, and cardon,Pachycereus pringlei. Two pentacyclic triterpene alcohols, lupeol and moretenol, were also isolated. Since no cholesterol was detected in any of the pollen samples, cactus bees would have to utilize the 24-alkyl sterols unchanged or convert these sterols to cholesterolvia dealkylation.

Journal of Insect Physiology, 1997

Journal of Insect Physiology, 2000

Five neuropeptides with known allatotropic or allatostatic activity in other insect species were ... more Five neuropeptides with known allatotropic or allatostatic activity in other insect species were examined for their effects on honey bee corpora allata. Using an in vitro radiochemical assay, we assessed the ability of these peptides to affect the biosynthesis of juvenile hormone III and its immediate precursor methyl farnesoate, as well as their effects on the conversion of methyl farnesoate into juvenile hormone. None of the allatostatins tested affected JH biosynthesis during the last larval instar of honey bee workers. Manduca sexta allatotropin, however, stimulated JH biosynthesis in a stage-specific and dose-dependent manner. Analysis of intraglandular contents of juvenile hormone and its precursor revealed that the allatotropin significantly increased JH precursor but did not overcome the stage-specific block in the terminal step of JH biosynthesis that is typical for early fifth-instar worker larvae. Studies also indicated that the allatotropic effect was reversible at the level of methyl farnesoate production.

Experientia, 1986

Summary Makisterone A, a 28-carbon ecdysteroid (molting hormone) has been isolated from the ovari... more Summary Makisterone A, a 28-carbon ecdysteroid (molting hormone) has been isolated from the ovaries of queen bees. Analysis by reversed-phase and silica high performance liquid chromatography (HPLC) in conjunction with a radioimmune assay (RIA) revealed about 11 ng of makisterone A present per gram of ovaries on a fresh weight basis. No C27 ecdysteroids were detected. The predominant neutral sterol present was 24-methylenecholesterol.

Archives of Insect Biochemistry and Physiology, 1993

Abstract Using high performance liquid chromatography in conjunction with radioimmunoassay and ma... more Abstract Using high performance liquid chromatography in conjunction with radioimmunoassay and mass spectrometry, the major ecdysteroid of the solitary cactus bee, Diadasia rinconis, was determined to be 20-hydroxyecdysone, with lesser amounts of ...

American Journal of Tropical Medicine and Hygiene, 2013

Technologies to detect bed bugs have not kept pace with their global resurgence. Early detection ... more Technologies to detect bed bugs have not kept pace with their global resurgence. Early detection is critical to prevent infestations from spreading. Detection based exclusively on bites is inadequate, because reactions to insect bites are non-specific and often misdiagnosed. Visual inspections are commonly used and depend on identifying live bugs, exuviae, or fecal droplets. Visual inspections are inexpensive, but they are time-consuming and unreliable when only a few bugs are present. Use of a dog to detect bed bugs is gaining in popularity, but it can be expensive, may unintentionally advertise a bed bug problem, and is not foolproof. Passive monitors mimic natural harborages; they are discreet and typically use an adhesive to trap bugs. Active monitors generate carbon dioxide, heat, a pheromone, or a combination to attract bed bugs to a trap. New technologies using DNA analysis, mass spectrometry, and electronic noses are innovative but impractical and expensive for widespread use.

Journal of Entomological Science, 2011

Apidologie, 1993

— Various saturated and unsaturated free fatty acids were tested for their antibiotic activ... more — Various saturated and unsaturated free fatty acids were tested for their antibiotic activity against Bacillus larvae, the causative agent of American foulbrood disease of honey bee larvae. Saturated compounds containing > 14 carbons were inactive. Antimicrobial activity could be restored to the longer chain length compounds by the addition of one or more double bonds. The antibiotic activity of fatty acids may make them suitable for use in the prevention and control of foulbrood diseases of honey bees.

Journal of Agricultural and Food Chemistry, Feb 21, 2007

A method was developed for the determination and confirmation of furazolidone, nitrofurazone, fur... more A method was developed for the determination and confirmation of furazolidone, nitrofurazone, furaltadone, and nitrofurantoin as their side-chain residues in honey using liquid chromatographytandem mass spectrometry (LC-MS/MS). An initial solid-phase extraction cleanup of the honey samples was followed by overnight hydrolysis and derivatization of the nitrofuran side-chain residues with 2-nitrobenzaldehyde. After pH adjustment and liquid-liquid extraction, the extracts were assayed by LC-MS/MS using electrospray ionization in the positive ion mode. The method was validated at concentrations ranging from 0.5 to 2.0 ppb with accuracies of 92-103% and coefficients of variation of e10%. The lowest calibration standard used (0.25 ppb) was defined as the limit of quantitation for all four nitrofuran side-chain residues. The extracts and standards were also used for confirmatory purposes. Honey from dosed beehives was assayed to study the stability of the nitrofuran residues and to demonstrate the effectiveness of the method.

J Exp Zool, 1982

In an effort to determine the nature of the juvenile hormone of a hemipteran insect, we have anal... more In an effort to determine the nature of the juvenile hormone of a hemipteran insect, we have analyzed the in vitro biosynthetic products of cultured corpora allata using thin layer chromatography and normal and reverse phase high performance liquid chromatography. We now report that the corpora allata of Dysdercus fasciatus (Hemiptera:Pynwhoridae) synthesize in vitro methyl 3,7,1 l-trimethyl-2E,6E, 10-dodecatrienoate, the methyl ester precursor of juvenile hormone 3.

Journal of Economic Entomology, 2014

Analysis of Sterols and Other Biologically Significant Steroids, 1989