24 research outputs found

    Variation in pre- and post-copulatory sexual selection on male genital size in two species of lygaeid bug

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    This study was funded by the Natural Environmental Research Council (DTG studentship 1109354 to LRD).Sexual selection has been shown to be the driving force behind the evolution of the sometimes extreme and elaborate genitalia of many species. Sexual selection may arise before and/or after mating, or vary according to other factors such as the social environment. However, bouts of selection are typically considered in isolation. We measured the strength and pattern of selection acting on the length of the male intromittent organ (or processus) in two closely related species of lygaeid seed bug: Lygaeus equestris and Lygaeus simulans. In both species, we measured both pre- and post-copulatory selection. For L. equestris, we also varied the experimental choice design used in mating trials. We found contrasting pre- and post-copulatory selection on processus length in L. equestris. Furthermore, significant pre-copulatory selection was only seen in mating trials in which two males were present. This selection likely arises indirectly due to selection on a correlated trait, as the processus does not interact with the female prior to copulation. In contrast, we were unable to detect significant pre- or post-copulatory selection on processus length in L. simulans. However, a formal meta-analysis of previous estimates of post-copulatory selection on processus length in L. simulans suggests that there is significant stabilising selection across studies, but the strength of selection varies between experiments. Our results emphasise that the strength and direction of sexual selection on genital traits may be multifaceted and can vary across studies, social contexts and different stages of reproduction.Publisher PDFPeer reviewe

    PC-402 Pioneer Venus orbiter spacecraft mission operational characteristics document

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    The operational characteristics of the Orbiter spacecraft and its subsystems are described. In extensive detail. Description of the nominal phases, system interfaces, and the capabilities and limitations of system level performance are included along with functional and operational descriptions at the subsystem and unit level the subtleties of nominal operation as well as detailed capabilities and limitations beyond nominal performance are discussed. A command and telemetry logic flow diagram for each subsystem is included. Each diagram encountered along each command signal path into, and each telemetry signal path out of the subsystem. Normal operating modes that correspond to the performance of specific functions at the time of specific events in the mission are also discussed. Principal backup means of performing the normal Orbiter operating modes are included

    Reduction mammaplasty in patients with history of breast cancer: The incidence of occult cancer and high-risk lesions

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    Introduction: Contralateral reduction mammaplasty is regularly included in the treatment of breast cancer patients. We analyzed the incidence of occult breast cancer and high-risk lesions in reduction mammaplasty specimens of women with previous breast cancer. We also analyzed if timing of reduction mammaplasty in relation to oncological treatment influenced the incidence of abnormal findings, and compared if patients with abnormal contralateral histopathology differed from the study population in terms of demographics. Materials and methods: The study consisted of 329 breast cancer patients, who underwent symmetrizing reduction mammaplasty between 1/2007 and 12/2011. The data was retrospectively analyzed for demographics, operative and histopathology reports, oncological treatment, and postoperative follow-up. Results: Reduction mammaplasty specimens revealed abnormal findings in 68 (21.5%) patients. High-risk lesions (ADH, ALH, and LCIS) were revealed in 37 (11.7%), and cancer in six (1.9%) patients. Abnormal histopathology correlated with higher age (p = 0.0053), heavier specimen (p = 0.0491), and with no previous breast surgery (p <0.001). Abnormal histopathological findings were more frequent in patients with reduction mammaplasty performed prior to oncological treatment (p <0.001), and in patients with immediate reconstruction (p = 0.0064). Conclusion: The incidences of malignant and high-risk lesions are doubled compared to patients without prior breast cancer. Patients with abnormal histopathology cannot be preoperatively identified based on demographics. If reduction mammaplasty is performed before oncological treatment, the incidence of abnormal findings is higher. In the light of our results, contralateral reduction mammaplasty with histopathological evaluation in breast cancer patients offers a sophisticated tool to catch those patients whose contralateral breast needs increased attention. (C) 2017 Elsevier Ltd. All rights reserved.Peer reviewe
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