346 research outputs found

    Genetic Factors Associated with Variation in Abundance of the Invasive Yellow Crazy Ant (Anoplolepis gracilipes)

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    A key component of successful invasion is the ability of an introduced population to reach sufficient abundance to persist, spread, and alter or dominate the recipient biological community. Genetic diversity is one of many factors that may contribute to population dynamics, but has important ramifications for biological fitness, and thus invasion success in the long term. I explored genetic factors associated with variation in abundance (i.e., differential invasion success) of the yellow crazy ant Anoplolepis gracilipes in the Indo-Pacific region, primarily focussing on Arnhem Land in Australia's Northern Territory. I explored five aspects that I hypothesised could contribute to variation in the abundance of this ant: 1) I investigated the unusual reproductive mode of A. gracilipes, and tested whether it involved dependent-lineage genetic caste determination (DL GCD) in Arnhem Land. In DL GCD systems populations require hybridisation between genetically distinct groups to produce both reproductive and worker castes. Asymmetry in the ratio of different lineages may result in low abundance and population collapse. I found no evidence for a DL GCD system in A. gracilipes, and thus its abundance in Arnhem Land does not appear to be constrained by any lineage ratio asymmetry. Worker reproduction (either of males or asexual production of other workers) also appeared unlikely. The reproductive mode of the species remains fascinating but enigmatic; 2) I explored whether multiple source populations were responsible for the observed variation in abundance in Arnhem Land (i.e., is abundance associated with propagule pressure, or populations from different sources), and if the population has diverged since introduction. The A. gracilipes population in Arnhem Land stemmed from a single source, and thus propagule pressure was apparently not responsible for variation in abundance. In contrast to many invasive ants, population divergence has occurred since introduction; 3) I tested the hypotheses that genetic variation was associated with variation in abundance in Arnhem Land, and that ecological success was density-dependent. While the population divergence found in Chapter 3 was not related to variation in abundance, genotypic diversity was higher in more abundant nest clusters. These more abundant nest clusters were in turn associated with lower native ant species diversity, and a difference in composition of the invaded ant community (i.e., greater ecological success); 4) I revisited the invasion of the yellow crazy ant in Tokelau to determine whether a haplotype that was linked to greater abundance and dominance of the ant community has increased in distribution. Although ants of the inferred dominant haplotype were implicated in most new invasions, their abundance was substantially lower than previously observed in Tokelau; 5) I conducted a preliminary analysis of the metagenomic diversity of A. gracilipes endogenous parasites and symbionts among populations from Christmas Island, Okinawa, Samoa and Arnhem Land. Bacterial community composition and diversity differed between the study populations. Variation in abundance among A. gracilipes populations in Arnhem Land was not due to parasite load on populations with low abundance. However, low abundance of A. gracilipes was correlated with lower microbial diversity overall, and higher prevalence of some groups, notably two that confer antibiotic properties. Together, my findings suggest that propagule pressure, reproductive mode and haplotype-specific effects do not appear to be associated with variation in A. gracilipes abundance. Other genetic factors I investigated do appear to be associated with the variation in A. gracilipes abundance and effects on the invaded ant communities. Genotypic diversity was positively related to the abundance of A. gracilipes in Arnhem Land, and this relationship may be affected by population divergence through population bottlenecks. In addition, differences in bacterial diversity among populations highlighted several candidate bacteria that could be associated with variation in abundance, which would be a topic of future work. Although genetic factors are often implicated in the successful establishment of invasive species, my thesis demonstrates that genetic factors may also be associated with post-establishment population dynamics

    Pain elicited by the Cold Pressor Test: A gender-comparative FACS coding study of spontaneous, faked and inhibited expressions.

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    Evolutionary theories of pain have conjectured a better ability of males to control their facial expressions of pain, and of females to express and communicate emotions through the face. The present study involved 24 participants (12 men; 12 women). Pain was induced via the Cold Pressor Test (CPT), and three expressive contexts (spontaneous, faked an inhibited) were created through instructions. Elicited pain expressions were FACS coded and frequency, indices were derived for the observed Action Units. Differences in the number of Actions Units activated by men and women were found in all conditions. AU25 occurred more frequently in women in the spontaneous context and AU24 in simulated condition. No gender differences were found concerning pain smiles

    Smile types, empathy and perceptions of social interaction

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    Smiles have been related to affective states (either positive or negative) and to communicative and interactive processes. The present study aims to evaluate the perception of 16 types of smiles as regards empathy and potential for social interaction, with a view at establishing the meaning accorded by decoders to differently FACS coded smiles. A smile data base collected in a clinical context was FACS coded and the observed AU facially reproduced by several certified coders. Images of these reproductions were made the target of a questionnaire presented to 209 participants. Judgments were elicited on a number of characteristics: empathy, dominance, approach tendency, confidence, cooperation, competence, sympathy, honesty, being positive and being negative. The Felt Smile and the Coordination Smile emerged as the most empathic ones, while Puzzled Smile and Embarrassment Smile were the less empathic

    A human MUTYH variant linking colonic polyposis to redox degradation of the [4Fe4S]²⁺ cluster

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    The human DNA repair enzyme MUTYH excises mispaired adenine residues in oxidized DNA. Homozygous MUTYH mutations underlie the autosomal, recessive cancer syndrome MUTYH-associated polyposis. We report a MUTYH variant, p.C306W (c.918C>G), with a tryptophan residue in place of native cysteine, that ligates the [4Fe4S] cluster in a patient with colonic polyposis and family history of early age colon cancer. In bacterial MutY, the [4Fe4S] cluster is redox active, allowing rapid localization to target lesions by long-range, DNA-mediated signalling. In the current study, using DNA electrochemistry, we determine that wild-type MUTYH is similarly redox-active, but MUTYH C306W undergoes rapid oxidative degradation of its cluster to [3Fe4S]^+, with loss of redox signalling. In MUTYH C306W, oxidative cluster degradation leads to decreased DNA binding and enzyme function. This study confirms redox activity in eukaryotic DNA repair proteins and establishes MUTYH C306W as a pathogenic variant, highlighting the essential role of redox signalling by the [4Fe4S] cluster

    A human MUTYH variant linking colonic polyposis to redox degradation of the [4Fe4S]²⁺ cluster

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    The human DNA repair enzyme MUTYH excises mispaired adenine residues in oxidized DNA. Homozygous MUTYH mutations underlie the autosomal, recessive cancer syndrome MUTYH-associated polyposis. We report a MUTYH variant, p.C306W (c.918C>G), with a tryptophan residue in place of native cysteine, that ligates the [4Fe4S] cluster in a patient with colonic polyposis and family history of early age colon cancer. In bacterial MutY, the [4Fe4S] cluster is redox active, allowing rapid localization to target lesions by long-range, DNA-mediated signalling. In the current study, using DNA electrochemistry, we determine that wild-type MUTYH is similarly redox-active, but MUTYH C306W undergoes rapid oxidative degradation of its cluster to [3Fe4S]^+, with loss of redox signalling. In MUTYH C306W, oxidative cluster degradation leads to decreased DNA binding and enzyme function. This study confirms redox activity in eukaryotic DNA repair proteins and establishes MUTYH C306W as a pathogenic variant, highlighting the essential role of redox signalling by the [4Fe4S] cluster

    The mediterranean sea we want

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    open58siThis paper presents major gaps and challenges for implementing the UN Decade of Ocean Science for Sustainable Development (2021-2030) in the Mediterranean region. The authors make recommendations on the scientific knowledge needs and co-design actions identified during two consultations, part of the Decade preparatory-phase, framing them in the Mediterranean Sea’s unique environmental and socio-economic perspectives. According to the ‘Mediterranean State of the Environment and Development Report 2020’ by the United Nations Environment Programme Mediterranean Action Plan and despite notable progress, the Mediterranean region is not on track to achieve and fully implement the Sustainable Development Goals of Agenda 2030. Key factors are the cumulative effect of multiple human-induced pressures that threaten the ecosystem resources and services in the global change scenario. The basin, identified as a climate change vulnerability hotspot, is exposed to pollution and rising impacts of climate change. This affects mainly the coastal zones, at increasing risk of extreme events and their negative effects of unsustainable management of key economic assets. Transitioning to a sustainable blue economy is the key for the marine environment’s health and the nourishment of future generations. This challenging context, offering the opportunity of enhancing the knowledge to define science-based measures as well as narrowing the gaps between the Northen and Southern shores, calls for a joint (re)action. The paper reviews the state of the art of Mediterranean Sea science knowledge, sets of trends, capacity development needs, specific challenges, and recommendations for each Decade’s societal outcome. In the conclusions, the proposal for a Mediterranean regional programme in the framework of the Ocean Decade is addressed. The core objective relies on integrating and improving the existing ocean-knowledge, Ocean Literacy, and ocean observing capacities building on international cooperation to reach the “Mediterranean Sea that we want”.openCappelletto M.; Santoleri R.; Evangelista L.; Galgani F.; Garces E.; Giorgetti A.; Fava F.; Herut B.; Hilmi K.; Kholeif S.; Lorito S.; Sammari C.; Lianos M.C.; Celussi M.; D'alelio D.; Francocci F.; Giorgi G.; Canu D.M.; Organelli E.; Pomaro A.; Sannino G.; Segou M.; Simoncelli S.; Babeyko A.; Barbanti A.; Chang-Seng D.; Cardin V.; Casotti R.; Drago A.; Asmi S.E.; Eparkhina D.; Fichaut M.; Hema T.; Procaccini G.; Santoro F.; Scoullos M.; Solidoro C.; Trincardi F.; Tunesi L.; Umgiesser G.; Zingone A.; Ballerini T.; Chaffai A.; Coppini G.; Gruber S.; Knezevic J.; Leone G.; Penca J.; Pinardi N.; Petihakis G.; Rio M.-H.; Said M.; Siokouros Z.; Srour A.; Snoussi M.; Tintore J.; Vassilopoulou V.; Zavatarelli M.Cappelletto M.; Santoleri R.; Evangelista L.; Galgani F.; Garces E.; Giorgetti A.; Fava F.; Herut B.; Hilmi K.; Kholeif S.; Lorito S.; Sammari C.; Lianos M.C.; Celussi M.; D'alelio D.; Francocci F.; Giorgi G.; Canu D.M.; Organelli E.; Pomaro A.; Sannino G.; Segou M.; Simoncelli S.; Babeyko A.; Barbanti A.; Chang-Seng D.; Cardin V.; Casotti R.; Drago A.; Asmi S.E.; Eparkhina D.; Fichaut M.; Hema T.; Procaccini G.; Santoro F.; Scoullos M.; Solidoro C.; Trincardi F.; Tunesi L.; Umgiesser G.; Zingone A.; Ballerini T.; Chaffai A.; Coppini G.; Gruber S.; Knezevic J.; Leone G.; Penca J.; Pinardi N.; Petihakis G.; Rio M.-H.; Said M.; Siokouros Z.; Srour A.; Snoussi M.; Tintore J.; Vassilopoulou V.; Zavatarelli M

    Oncoplastic breast consortium recommendations for mastectomy and whole breast reconstruction in the setting of post-mastectomy radiation therapy

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    Aim: Demand for nipple-and skin-sparing mastectomy (NSM/SSM) with immediate breast reconstruction (BR) has increased at the same time as indications for post-mastectomy radiation therapy (PMRT) have broadened. The aim of the Oncoplastic Breast Consortium initiative was to address relevant questions arising with this clinically challenging scenario. Methods: A large global panel of oncologic, oncoplastic and reconstructive breast surgeons, patient advocates and radiation oncologists developed recommendations for clinical practice in an iterative process based on the principles of Delphi methodology. Results: The panel agreed that surgical technique for NSM/SSM should not be formally modified when PMRT is planned with preference for autologous over implant-based BR due to lower risk of long-term complications and support for immediate and delayed-immediate reconstructive approaches. Nevertheless, it was strongly believed that PMRT is not an absolute contraindication for implant-based or other types of BR, but no specific recom-mendations regarding implant positioning, use of mesh or timing were made due to absence of high-quality evidence. The panel endorsed use of patient-reported outcomes in clinical practice. It was acknowledged that the shape and size of reconstructed breasts can hinder radiotherapy planning and attention to details of PMRT techniques is important in determining aesthetic outcomes after immediate BR. Conclusions: The panel endorsed the need for prospective, ideally randomised phase III studies and for surgical and radiation oncology teams to work together for determination of optimal sequencing and techniques for PMRT for each patient in the context of BRPeer reviewe
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