54 research outputs found

    Intra-trackway morphological variations due to substrate consistency: the El Frontal dinosaur tracksite (Lower Cretaceous, Spain).

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    An ichnological and sedimentological study of the El Frontal dinosaur tracksite (Early Cretaceous, Cameros basin, Soria, Spain) highlights the pronounced intra-trackway variation found in track morphologies of four theropod trackways. Photogrammetric 3D digital models revealed various and distinct intra-trackway morphotypes, which reflect changes in footprint parameters such as the pace length, the track length, depth, and height of displacement rims. Sedimentological analyses suggest that the original substrate was non-homogenous due to lateral changes in adjoining microfacies. Multidata analyses indicate that morphological differences in these deep and shallow tracks represent a part of a continuum of track morphologies and geometries produced by a gradient of substrate consistencies across the site. This implies that the large range of track morphologies at this site resulted from similar trackmakers crossing variable facies. The trackways at the El Frontal site present an exemplary case of how track morphology, and consequently potential ichnotaxa, can vary, even when produced by a single trackmaker

    Age and Disability Employment Discrimination: Occupational Rehabilitation Implications

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    Introduction As concerns grow that a thinning labor force due to retirement will lead to worker shortages, it becomes critical to support positive employment outcomes of groups who have been underutilized, specifically older workers and workers with disabilities. Better understanding perceived age and disability discrimination and their intersection can help rehabilitation specialists and employers address challenges expected as a result of the evolving workforce. Methods Using U.S. Equal Employment Opportunity Commission Integrated Mission System data, we investigate the nature of employment discrimination charges that cite the Americans with Disabilities Act or Age Discrimination in Employment Act individually or jointly. We focus on trends in joint filings over time and across categories of age, types of disabilities, and alleged discriminatory behavior. Results We find that employment discrimination claims that originate from older or disabled workers are concentrated within a subset of issues that include reasonable accommodation, retaliation, and termination. Age-related disabilities are more frequently referenced in joint cases than in the overall pool of ADA filings, while the psychiatric disorders are less often referenced in joint cases. When examining charges made by those protected under both the ADA and ADEA, results from a logit model indicate that in comparison to charges filed under the ADA alone, jointly-filed ADA/ADEA charges are more likely to be filed by older individuals, by those who perceive discrimination in hiring and termination, and to originate from within the smallest firms. Conclusion In light of these findings, rehabilitation and workplace practices to maximize the hiring and retention of older workers and those with disabilities are discussed

    Mechanisms underlying the growth inhibitory effects of the cyclo-oxygenase-2 inhibitor celecoxib in human breast cancer cells

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    INTRODUCTION: Inhibitors of cyclo-oxygenase (COX)-2 are being extensively studied as anticancer agents. In the present study we evaluated the mechanisms by which a highly selective COX-2 inhibitor, celecoxib, affects tumor growth of two differentially invasive human breast cancer cell lines. METHODS: MDA-MB-231 (highly invasive) and MDA-MB-468 (moderately invasive) cell lines were treated with varying concentrations of celecoxib in vitro, and the effects of this agent on cell growth and angiogenesis were monitored by evaluating cell proliferation, apoptosis, cell cycle arrest, and vasculogenic mimicry. The in vitro results of MDA-MB-231 cell line were further confirmed in vivo in a mouse xenograft model. RESULTS: The highly invasive MDA-MB-231 cells express higher levels of COX-2 than do the less invasive MDA-MB-468 cells. Celecoxib treatment inhibited COX-2 activity, indicated by prostaglandin E(2 )secretion, and caused significant growth arrest in both breast cancer cell lines. In the highly invasive MDA-MB-231 cells, the mechanism of celecoxib-induced growth arrest was by induction of apoptosis, associated with reduced activation of protein kinase B/Akt, and subsequent activation of caspases 3 and 7. In the less invasive MDA-MB-468 cells, growth arrest was a consequence of cell cycle arrest at the G(0)/G(1 )checkpoint. Celecoxib-induced growth inhibition was reversed by addition of exogenous prostaglandin E(2 )in MDA-MB-468 cells but not in MDA-MB-231 cells. Furthermore, MDA-MB-468 cells formed significantly fewer extracellular matrix associated microvascular channels in vitro than did the high COX-2 expressing MDA-MB-231 cells. Celecoxib treatment not only inhibited cell growth and vascular channel formation but also reduced vascular endothelial growth factor levels. The in vitro findings corroborated in vivo data from a mouse xenograft model in which daily administration of celecoxib significantly reduced tumor growth of MDA-MB-231 cells, which was associated with reduced vascularization and increased necrosis in the tumor mass. CONCLUSION: The disparate molecular mechanisms of celecoxib-induced growth inhibition in human breast cancer cells depends upon the level of COX-2 expression and the invasive potential of the cell lines examined. Data suggest a role for COX-2 not only in the growth of cancer cells but also in activating the angiogenic pathway through regulating levels of vascular endothelial growth factor

    Neoadjuvant treatment of pancreatic adenocarcinoma: a systematic review and meta-analysis of 5520 patients

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    LGBTQ parenting post heterosexual relationship dissolution

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    The chapter examines parenting among sexual and gender minorities post heterosexual relationship dissolution (PHRD). Reviewing the literature around intersecting identities of LGBTQ parents, we consider how religion, race, and socioeconomic status are associated with routes into and out of heterosexual relationships and variation in the lived experience of sexual and gender identity minorities, in particular how LGBTQ parents PHRD feel about being out. Further consideration is given to examining how family relationships change and develop as parental sexual and/or gender identity changes. We also explore the impact of PHRD identity and parenthood on new partnerships and stepfamily experiences. The chapter addresses the reciprocal relationship between research on LGBTQ parenting and policy and legal influences that impact upon the experience of LGBTQ parenting PHRD when custody and access are disputed. Finally, the chapter includes future research directions and implications for practice in an area that has been revitalized in recent years

    Improved Upper Limit on the Neutrino Mass from a Direct Kinematic Method by KATRIN

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    We report on the neutrino mass measurement result from the first four-week science run of the Karlsruhe Tritium Neutrino experiment KATRIN in spring 2019. Beta-decay electrons from a high-purity gaseous molecular tritium source are energy analyzed by a high-resolution MAC-E filter. A fit of the integrated electron spectrum over a narrow interval around the kinematic end point at 18.57 keV gives an effective neutrino mass square value of (1.01.1+0.9)eV2(−1.0^{+0.9}_{−1.1}) eV^2. From this, we derive an upper limit of 1.1 eV (90% confidence level) on the absolute mass scale of neutrinos. This value coincides with the KATRIN sensitivity. It improves upon previous mass limits from kinematic measurements by almost a factor of 2 and provides model-independent input to cosmological studies of structure formation

    Ecological patterns of blood-feeding by kissing-bugs (Hemiptera: Reduviidae: Triatominae)

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