1,124 research outputs found
Letter to Sheriff Sweeney from Carl Rossbach, July 15, 1954, Cuyahoga County Sheriff\u27s Office
No full textLetter to Sheriff Sweeney from Deputy Sheriff Carl Rossbach regarding Dr. Lester Hoversten. Rossbach and Yettra visited Holland American Lines Steamship Offices in Cleveland, Ohio where they learned that Dr. Hoversten had booked a trip to Berlin at the end of July 1954. Hoversten cancelled that reservation on July 12, 1954. The report also gives details of an interview with both Dr. Robert Stevenson and Dr. Stephen Sheppard. Hoversten was staying with Stevenson in Kent, Ohio on July 3-4, 1954. Stevenson stated that Hoversten went to bed around midnight and that the dog would have barked if Hoversten had left the premises during the night. Dr. Stephen Sheppard stated that Hoversten told him that he was expecting a cash loan from Dr. Sam but that Marilyn\u27s death had confused things. Dr. Stephen Sheppard told Hoversten that he should seek a loan elsewhere
A hipertrofia do coração : e o augmento da tensão do sangue
No full textAção da nitro-clychirina na atrophia dos rins, pelo professor M. J. Rossbach, de Iena (Tradução especialmente para a Gazeta Médica da Bahia, pelo Dr. Tillemont Fontes
Interspecific competition between Diadegma semiclausum Hellen and Diadegma mollipla (Holmgren), parasitoids of the diamondback moth, Plutella xylostella (L), feeding on a new host plant
No full textInterspecific competition between an introduced parasitoid species aimed at controlling a herbivorous pest species and a native parasitoid parasitising the same host may influence the success of classical biological control programmes. In Kenya, interspecific competition between an introduced and a local parasitoid on two diamondback moth populations (DBM, Plutella xylostella) was investigated on two different host plants. We tested simultaneous and delayed competition of the local parasitoid Diadegma mollipla Holmgren and its exotic congenus D. semiclausum Hellen on a newly aquired DBM host plant (snowpea) in the laboratory. Under simultaneous competition, D. mollipla produced more progeny than D. semiclausum on snowpea. A head start of D. Mollipla, of four and eight hours before its congenus was introduced, resulted in a similar number of progeny of both species. In delayed competition (time intervals of 24h, 48h and 72h), progeny production was similar for both parasitoids when the time interval was 24h, irrespective of which species parasitized first. More progeny was produced by the species which attacked first, when the time interval was greater than 24h, although it was only significant at 72 h. Competitive abilites of both parasitoids on the new host plant differed largely between laboratory and semi-field conditions. The influence of two host plants (snowpea and cabbage) on competition was studied in the greenhouse with different host and parasitoid densities. Parasitism levels of D. semiclausum were significantly higher than those of D. mollipla, regardless of host plant, host and parasitoid densities, but progeny production of D. mollipla on snowpea was still slightly higher than on cabbage. As compared to the confinement of parasitoids and larvae to small containers, D. mollipla parasitized very few larvae in the cages. Competitive ability of the two parasitoid species tested was influenced both by the density of the searching females and by parameters related to either the host plant and/or the herbivorous hosts.the German Research Foundation (DFG
Parasitism of Plutella xylostella L. feeding on a new host plant
No full textThe diamondback moth Plutella xylostella L. (Lepidoptera: Plutellidae) is known to be an oligophagous pest on crucifers. Recently, a population of diamondback moths was found to infest sugar snap and snowpea in the Rift Valley in Kenya, causing heavy damage. The effect of resident parasitoids on diamondback moths in snowpea (Pisum sativum L.) was studied in the field. In addition, parasitism of diamondback moths by the newly introduced parasitoid Diadegma semiclausum (Hellen) was evaluated. Snowpea provided an enemy-free space for diamondback moths. Local parasitoids attacked diamondback moths only sporadically and in very low numbers (mean of 0.25 individuals/ 20 plants during the first study period) on diamondback moths on pea compared with a mean of 15.4 individuals/20 plants on kale (Brassica oleracea acephala L.) However, diamondback moth density was higher on kale (mean of 61.1 larvae/20 plants) than on snowpea (mean of 11.4 larvae/20 plants). Differential diamondback moth infestation and level of parasitism might have been affected by a fungal infection (Ascochyta) of the pea plants. In both crops, the most abundant parasitoid was Oomyzus sokolowskii Kurdjumov. After the release of D. semiclausum, the number of diamondback moths in kale decreased drastically to < 2 individuals/20 plants; however, the parasitoid had little effect on diamondback moths on snowpea. Percentage parasitism on snowpea increased from 2.3 to 4%, whereas on kale, it increased from 25.6 to 75.7%. A host plant expansion could be of future advantage for the diamondback moth to avoid higher enemy pressure caused by D. semiclausum
A Tide of Change: Stories of Marine Conservation Success
No full textSusann Rossbach from Red Sea Global, Lead Author for Saudi Arabia's Frontiers Planet Prize winning paper, presents compelling evidence that marine conservation success is not only possible, it’s already happening. By analyzing 217 verified case studies, her research reveals the social, ecological, and institutional ingredients behind effective ocean stewardship. Rossbach highlights the power of local engagement, multi-stakeholder collaboration, and targeted action against high-impact pressures like overfishing and pollution, reframing marine conservation as a dynamic, hopeful frontier in achieving global sustainability and staying within planetary boundaries.
The thought piece can be found on the Frontiers Planet Prize website and can be accessed via this link.
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Host shift to peas in the diamondback moth Plutella xylostella (Lepidoptera: Plutellidae) and response of its parasitoid Diadegma mollipla (Hymenoptera: Ichneumonidae)
No full textHost shifts in herbivorous insects are thought to sometimes provide enemy-free space on the novel host plant. A population of the diamondback moth Plutella xylostella (Linnaeus), an oligophagous pest on crucifers, recently shifted to sugar snap- and snowpeas (Pisum sativum) in Kenya, resulting in heavy damage to these crops. The impact of this host shift on the interaction with Diadegma mollipla (Holmgren), one of the most frequent parasitoid species attacking P. xylostella in this area, was investigated. Parasitism rates and development of two strains of D. mollipla, one reared from a cabbage-feeding strain of P. xylostella and the second from the new pea-feeding strain, changed based on the host-plant that P. xylostella fed upon, with both parasitoid strains more effective on the novel host plant. Parasitism by the cabbage-D. mollipla strain on P. xylostella infesting peas was four times higher than on P. xylostella infesting cabbage when a single plant species was present. However, when both crops were offered together, the level of parasitism dropped to the level seen when cabbage was offered alone. Diadegma mollipla developed on both hosts, but cabbage-D. mollipla had a longer total development time. Pupae of cabbage-feeding P. xylostella were significantly heavier than pupae of pea-feeding P. xylostella and parasitism had no influence on these differences. Diadegma mollipla preferred to parasitize the pea-feeding P. xylostella. Thus, the host shift by P. xylostella to a novel host plant did not necessarily provide enemy-free space, with the parasitoid species tested. The implications of these findings for the host-parasitoid relationship are discussed
Generalism versus specialism: Responses of Diadegma mollipla (Holmgren) and Diadegma semiclausum (Hellen), to the host shift of the diamondback moth (Plutella xylostella L.) to peas
No full textA population of the diamondback moth Plutella xylostella (L.) (Lepidoptera: Plutellidae) (DBM) was recently found to infest sugar snap- and snowpeas in the Rift Valley in Kenya, causing heavy damage. The influence of this host shift on host location preferences of two parasitoids was investigated: The indigenous Diadegma mollipla (Holmgren) regarded as a relative generalist, and Diadegma semiclausum(Hellen), regarded as highly specific to DBM. The attractiveness of different odour sources was compared for the two parasitoid species using a Y-tube olfactometer using naive females. D. mollipla was not significantly attracted to any cabbage related odours but showed a significant preference for the DBM infested pea plant when tested against clean air. D. semiclausum was highly attracted to the undamaged cabbage plant and odours related to cabbage. On the other hand, peas infested with DBM, showed no attractiveness to this parasitoid. The results showed that specialisation of D. semiclausum is mediated by host plant signals, associated with crucifers, which are not encountered in DBM feeding on peas. For D. mollipla,although a frequent parasitoid on DBM in crucifers, volatiles emitted by these plants might not be used as primary cues for host location. This species may respond largely to chemicals yet unknown and associated with a variety of plant-herbivore interactions
Bryozoa diversity and abundance in Phyllophora crispa (Rhodophyta) mats and Posidonia oceanica meadows near Giglio Island (Tyrrhenian Sea, Italy)
No full textDataset on the epibenthic abundance of Bryozoa on P. crispa and P. oceanica habitats in the NW Mediterranean Sea (Giglio Island, Italy). Samples were obtained via SCUBA diving in summers 2018 and 2019 and analyzed by microscopic determination and counting of specimens. Sampling was part of a larger project on the diversity of the epiphytic invertebrate community on P. crispa mats in the area. The dataset includes details on the sampling efforts, diversity indices (Shannon (H'), Pielou (J')), and density of colonies m-². The numbers of individuals per family were counted on the subsamples. Densities of bryozoa (Dens) were extrapolated using wet weights of the sub- and main sample, as well as the measured surface area of the subsample. Detailed descriptions of the calculations can be found in the corresponding publication (Rossbach et al. (in review))
Can low release numbers lead to establishment and spread of an exotic parasitoid: The case of the diamondback moth parasitoid, Diadegma semiclausum (Hellen), in East Africa
No full textFrom 2001 onwards, Diadegma semiclausum, an exotic parasitoid of the diamondback moth, was introduced and released in Kenya, Tanzania and Uganda. Contrary to common practice where thousands of parasitoids are released, we released very low numbers, 125 females in Kenya, 160 in Uganda and 350 in Tanzania. About 2 years after this single release, the establishment and natural spread of the parasitoids was assessed in all release areas. Two methods were employed: in Kenya, a grid with equidistant points in the four cardinal directions (2-50 km) with the release area in the centre was used and collections were made 27 months after release at the predetermined points. The parasitoid was found up to a distance of 30km from the release site. In Tanzania and Uganda, surveys were made starting from the release area following major roads. At regular intervals, fields were inspected and their position recorded with a Geographic Positioning System (GPS). The results of a field survey conducted 24 months after release indicate that in Tanzania, the parasitoid had spread > 20 km from the release site while in Uganda, the spread was > 30 km. Wherever D. semiclausum was collected, it was the major parasitoid species. Indigenous parasitoids collected were Oomyzus sokolowskii (Hym.: Eulophidae), Diadegma mollipla (Hym.: Ichneumonidae) and Apanteles sp. (Hym.: Braconidae). Overall parasitism and the contribution of the introduced parasitoid to the control of diamondback moth population tended to decrease with increasing distance from the release point. The introduced parasitoid had displaced the indigenous species wherever it was well established. (C) 2007 Elsevier Ltd. All rights reserved
Abenteurer als Helden der Literatur oder: Wie wurden oder machten sich Schwindler, Spione, Kolonialisten oder Militars zu grossen Gestalten der europaischen Literatur? = Adventurers in literature
No full textPapers from the Internationales Colloquium "Abenteurer als Helden der Literatur vom 16. bis 20. Jahrhundert," held Feb. 16-19, 2000, in Bonn, Germany.Sabine Kleine-Rossbach and Horst Albert Glaserhttp://trove.nla.gov.au/work/3026543
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