Bioassay of the Nucleopolyhedrosis Virus of \u3ci\u3eNeodiprion Sertifer\u3c/i\u3e (Hymenoptera: Diprionidae)

Linear regression analysis of probit mortality versus several concentrations of nucleo- polyhedrosis virus of Neodiprion sertifer resulted in the equation Y = 2.170 + 0.872X. An LC50 was calculated at 1758 PIB/mL Also, the incubation time of the virus was dependent on Its concentration

Temperature and Crowding Effects on Virus Manifestation in Neodiprion Sertifer (Hymenoptera: Diprionidae) Larvae

Temperature and (or) crowding (larval density) functioned as stressors in the induction of symptoms associated with the nucleopolyhedrosis virus of the European pine sawfly, Neodiprion sertifer, Subsamptes of larvae maintained at 30 and 35°C, with three levels of larval density each (20, 60, and 100/shoot) which had died under these conditions, revealed the presence of polyhedral inclusion bodies under microscopic examination. In contrast, larvae maintained at 25°C with the same three larval density levels experienced no symptoms of virus infection or mortality, The latter was consistent with field observations when temperatures during larval development ranged from 14°C to 27°C and larval densities were in the same general range

Field Release of Virus-Sprayed Adult Parasitoids of the European Pine Sawfly (Hymenoptera: Diprionidae) in Wisconsin

Rapid field release of adult parasitoids sprayed with the nucleopolyhedrosis virus of the European pine sawfly successfully transferred the virus to feeding larval colonies

Homalg: A meta-package for homological algebra

The central notion of this work is that of a functor between categories of finitely presented modules over so-called computable rings, i.e. rings R where one can algorithmically solve inhomogeneous linear equations with coefficients in R. The paper describes a way allowing one to realize such functors, e.g. Hom, tensor product, Ext, Tor, as a mathematical object in a computer algebra system. Once this is achieved, one can compose and derive functors and even iterate this process without the need of any specific knowledge of these functors. These ideas are realized in the ring independent package homalg. It is designed to extend any computer algebra software implementing the arithmetics of a computable ring R, as soon as the latter contains algorithms to solve inhomogeneous linear equations with coefficients in R. Beside explaining how this suffices, the paper describes the nature of the extensions provided by homalg.Comment: clarified some points, added references and more interesting example

Host plant mediates foraging behavior and mutual interference among adult Stethorus gilvifrons (Coleoptera: Coccinellidae) preying on Tetranychus urticae (Acari: Tetranychidae)

Citation: Bayoumy, M. H., Osman, M. A., & Michaud, J. P. (2014). Host plant mediates foraging behavior and mutual interference among adult Stethorus gilvifrons (Coleoptera: Coccinellidae) preying on Tetranychus urticae. Retrieved from http://krex.ksu.eduPhysical plant characteristics can influence predator foraging and their behavioral responses to each other. This study examined the searching efficiency and functional response of adult female Stethorus gilvifrons Mulsant foraging for Tetranychus urticae Koch (Acari: Tetranychidae) on castor bean, common bean, and cucumber leaves. Experiments conducted on leaf discs in arenas for 12 h revealed a type II functional response for S. gilvifrons on all host plants. Per capita searching efficiency and killing power decreased with increasing predator density on all plants, but most notably on common bean, the plant with the highest prey consumption rates, due to greater mutual interference. Attack rates were highest on common bean and lowest on castor bean, whereas handling times were shortest on common bean and longest on cucumber, such that the daily predation rate was maximal on common bean. Host plant interacted with predator and prey densities to affect searching efficiency and functional response, the differences in mite consumption among host plants increasing with predator and prey densities. The waxy layers of castor bean leaves and high trichome counts of cucumber leaves appeared to reduce predator foraging efficiency. Thus, the efficacy of S. gilvifrons against T. urticae is likely to be greatest on plants such as Phaeseolus vulgaris L. that have relatively smooth leaves

One-second coherence for a single electron spin coupled to a multi-qubit nuclear-spin environment

Single electron spins coupled to multiple nuclear spins provide promising multi-qubit registers for quantum sensing and quantum networks. The obtainable level of control is determined by how well the electron spin can be selectively coupled to, and decoupled from, the surrounding nuclear spins. Here we realize a coherence time exceeding a second for a single electron spin through decoupling sequences tailored to its microscopic nuclear-spin environment. We first use the electron spin to probe the environment, which is accurately described by seven individual and six pairs of coupled carbon-13 spins. We develop initialization, control and readout of the carbon-13 pairs in order to directly reveal their atomic structure. We then exploit this knowledge to store quantum states for over a second by carefully avoiding unwanted interactions. These results provide a proof-of-principle for quantum sensing of complex multi-spin systems and an opportunity for multi-qubit quantum registers with long coherence times

Optimization and Application of Chromosome In Situ Suppression Hybridization

The overall aim of this project was to develop the technique of chromosomal in situ suppression (CISS) hybridization using whole chromosome specific libraries (chromosome painting) and to apply it to the investigation of diagnostic problems in clinical cytogenetics. Initially to gain experience with non-isotopic in situ hybridization, repetitive target probes DYS59 (GMY10) and DYS58 (GMGY7) were used. This provided experience in labelling of probe with biotin, hybridization and detection conditions (alkaline phosphatase detection) and analysis of results. The technique was reliable and sensitive and was applied to map the gene for angiotensinogen to 1q42. In the later part of this initial work, a fluorescence detection technique using fluoresceinated avidin and goat biotinylated anti-avidin was applied to confirm an isochromosomes Yp and Yq using DYS59 (GMGY10) and DYS58 (GMGY7) probes. The study then progressed into the development of the chromosome painting technique. Difficulties were encountered in preparing the working library probe from the chromosome 21 specific library and a major part of the work involved solving these problems. The libraries were found to be less concentrated than indicated by the supplier. Consequently, the amplification and purification following established protocols failed to produce a concentrated DNA library in the phage. However, a good yield of the DNA library was achieved by using trypticase in the culture media and high purity agarose as the top agar during the amplification. Labelling of the library by nick-translation and random priming did not achieve decoration of the whole chromosome 21 but direct labelling of Biotin-ll-dUTP by polymerase chain reaction (PCR) amplification was found to be efficient and overcame the problem of non-homogenous painting of the target chromosome. This direct labelling approach had difficulties in the cleaning and concentration of the PCR product. These were overcome by cleaning with Sephadex G-50 column chromatography and freeze drying of eluate. Once homogeneous painting had been achieved the probe was applied for chromosome painting. Many problems and parameters for the optimum working conditions were identified in this part of study. These are either independent or/and related to various conditions involved during all stages of the technique. The maximum final concentration of the DNA mixture per slide was 10ug/10ul and increasing the ratio of the probe and/or the unlabelled DNA did not improve either the quality of suppression or the hybridization signal. Addition of human cot 1-DNA in 1 to 4 ratio with total human DNA gave better suppression. Denaturation of labelled probe and competitor DNA mixture was optimum at 75C for 8 minutes and for optimum preannealling, the mixture was prehybridized for a minimum of 60 minutes at 37C. Slides were only treated with RNase when necessary and not with Proteinase K as the latter tended to wash the cells off the slide. Denaturation of the slides was carried out at 70-75C in 70% formamide/2XSSC for a maximum of 8 minutes. At temperature of 80C the chromosome morphology was found to be distorted. Hybridization when carried out at 37C for 15 to 20 hours showed good hybridization with chromosome morphology undisturbed. Hybridization at 42-45C showed crystallization and heavy background deposits. Posthybridization washing in three changes of 50% formamide/2XSSC at 45C was found to be optimal in producing a clean background. In between detection washing using 0.1M sodium phosphate buffer with 0.1% Nonidet P-40 carried out at room temperature is sufficient to remove excess stain as compared to other washing buffers such as 2XSSC or 4XSSC containing Triton-X or Tween 20. Detection was carried out at room temperature for 15-20 minutes and any slide dried during this stage produced high autofluorescence of fluoresceinated avidin which was difficult to remove by washing. A single amplification cycle was sufficient to enhance the decoration of chromosome 21. Prebanding of slides prior to hybridization did not affect the target chromosomes, however, incomplete destaining did hinder probe penetration and interfere with counterstaining. It was found that refixing of slides (either new or old slides) in methanol:acetic acid (3:1) before denaturation tended to improve the hybridization result as well as reducing background signal. In general, the technical difficulties were related to either probe preparation, poor hybridization, non-homogeneous painting or high background but with modifications of the parameters as detailed above the method was shown to be reliable and reproducible. Chromosomes obtained from phytohaemagglutinin (PHA) stimulated blood cultures were used during the initial phase. Subsequently, painting was successfully performed on cytogenetically normal metaphase and prometaphase samples of cultured amniocytes, lymphoblastoid cell lines, chorionic villus samples (CVS) and bone marrow preparations. The results showed that all normal chromosome 21s in all types of preparation except direct chorionic villus sample (CVS) were intensely painted and distinctly recognisable. However, results with interphase nuclei were not encouraging. The signals produced were not consistent enough to produce as reliable results. Twelve cases with cytogenetic abnormalities involving the chromosome 21 were investigated using chromosome painting. These results proved that chromosome painting can be used for rapid identification of individual chromosomes and is complementary and confirmatory to conventional karyotyping and as such is predicted to have a future routine diagnostic role in clinical cytogenetics in additions to its research applications

Utilization of brackish water areas for prawn culture

Maximum utilization of the vast brackish water areas constituted by the various estuaries, swams, inland bays, tida1 pools, lakes and brackish waters

Results of the tagging experiments on the Indian Spiny lobster, Panulirus homarus (Linnaeus) — Movement and growth

Mark-recovery experiments conducted with the help of suture tags on Indian spiny lobster Panulirus homarus (Linn.) showed that their movement in the fishing ground is of a very restricted nature. Long migratory movements were not observed. The species grows very fast and attains commercial size by the end of first year after the puerulus stage settles down to the bottom of the fishing ground. The growth rate slows down after the second year! Sizes attained at successive ages have been estimated with the help of von Bertalanffy's growth equation. The commercial fishery is largely supported by 1 st and 2nd year animals