304 research outputs found

    Resin Flow in Loblolly and Shortleaf Pines Used by Red-Cockaded Woodpeckers

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    We measured resin flow in loblolly (Pinus taeda L.) and shortleaf (Pinus echinata Mill.) pines in stands used by red-cockaded woodpecker, Picoides borealis (Vieillot), in the Angelina and Davy Crockett National Forests in eastern Texas. We also measured resin flow in a mature loblolly pine stand not used by the woodpeckers. Resin flow varied by study area, species, and stand position. In woodpecker stands, pines experiencing low levels of competition seemed better able to tolerate the continual resin drainage associated with red-cockaded woodpecker resin well pecking. In the Angelina National Forest, all new cavity trees excavated during the study were on forest edges. In the non-woodpecker stand, edge trees had significantly better resin flow. These results indicate that the woodpeckers choose trees most likely to be good resin producers. They also indicate that silviculture in loblolly and shortleaf pine stands should favor edge and an open stand habit when red-cockaded woodpeckers are a major management consideration and that potential resin production can be measured in both cavity pines, and pines being considered for red-cockaded woodpecker introduction

    Evaluating different methods of MR-based motion correction in simultaneous PET/MR using a head phantom moved by a robotic system

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    BACKGROUND: Due to comparatively long measurement times in simultaneous positron emission tomography and magnetic resonance (PET/MR) imaging, patient movement during the measurement can be challenging. This leads to artifacts which have a negative impact on the visual assessment and quantitative validity of the image data and, in the worst case, can lead to misinterpretations. Simultaneous PET/MR systems allow the MR-based registration of movements and enable correction of the PET data. To assess the effectiveness of motion correction methods, it is necessary to carry out measurements on phantoms that are moved in a reproducible way. This study explores the possibility of using such a phantom-based setup to evaluate motion correction strategies in PET/MR of the human head. METHOD: An MR-compatible robotic system was used to generate rigid movements of a head-like phantom. Different tools, either from the manufacturer or open-source software, were used to estimate and correct for motion based on the PET data itself (SIRF with SPM and NiftyReg) and MR data acquired simultaneously (e.g. MCLFIRT, BrainCompass). Different motion estimates were compared using data acquired during robot-induced motion. The effectiveness of motion correction of PET data was evaluated by determining the segmented volume of an activity-filled flask inside the phantom. In addition, the segmented volume was used to determine the centre-of-mass and the change in maximum activity concentration. RESULTS: The results showed a volume increase between 2.7 and 36.3% could be induced by the experimental setup depending on the motion pattern. Both, BrainCompass and MCFLIRT, produced corrected PET images, by reducing the volume increase to 0.7–4.7% (BrainCompass) and to -2.8–0.4% (MCFLIRT). The same was observed for example for the centre-of-mass, where the results show that MCFLIRT (0.2–0.6 mm after motion correction) had a smaller deviation from the reference position than BrainCompass (0.5–1.8 mm) for all displacements. CONCLUSIONS: The experimental setup is suitable for the reproducible generation of movement patterns. Using open-source software for motion correction is a viable alternative to the vendor-provided motion-correction software. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40658-022-00442-6

    Student Ensemble: Wind Symphony

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    Center for the Performing ArtsApril 24, 2016Sunday Afternoon4:00 p.m

    A life in progress: motion and emotion in the autobiography of Robert M. La Follette

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    This article is a study of a La Follette’s Autobiography, the autobiography of the leading Wisconsin progressive Robert M. La Follette, which was published serially in 1911 and, in book form, in 1913. Rather than focusing, as have other historians, on which parts of La Follette’s account are accurate and can therefore be trusted, it explains instead why and how this major autobiography was conceived and written. The article shows that the autobiography was the product of a sustained, complex, and often fraught series of collaborations among La Follette’s family, friends, and political allies, and in the process illuminates the importance of affective ties as well as political ambition and commitment in bringing the project to fruition. In the world of progressive reform, it argues, personal and political experiences were inseparable

    A review of Monte Carlo simulations of polymers with PERM

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    In this review, we describe applications of the pruned-enriched Rosenbluth method (PERM), a sequential Monte Carlo algorithm with resampling, to various problems in polymer physics. PERM produces samples according to any given prescribed weight distribution, by growing configurations step by step with controlled bias, and correcting "bad" configurations by "population control". The latter is implemented, in contrast to other population based algorithms like e.g. genetic algorithms, by depth-first recursion which avoids storing all members of the population at the same time in computer memory. The problems we discuss all concern single polymers (with one exception), but under various conditions: Homopolymers in good solvents and at the Θ\Theta point, semi-stiff polymers, polymers in confining geometries, stretched polymers undergoing a forced globule-linear transition, star polymers, bottle brushes, lattice animals as a model for randomly branched polymers, DNA melting, and finally -- as the only system at low temperatures, lattice heteropolymers as simple models for protein folding. PERM is for some of these problems the method of choice, but it can also fail. We discuss how to recognize when a result is reliable, and we discuss also some types of bias that can be crucial in guiding the growth into the right directions.Comment: 29 pages, 26 figures, to be published in J. Stat. Phys. (2011

    Gonadotropin-releasing hormone analogs during chemotherapy for preservation of ovarian function and fertility in premenopausal early breast cancer patients: a systematic review and meta-analysis of individual patient-level data

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    Purpose The role of temporary ovarian suppression with gonadotropin-releasing hormone agonists (GnRHa) during chemotherapy as a strategy to preserve ovarian function and fertility in premenopausal women remains controversial. This systematic review and meta-analysis using individual patient\u2013level data was conducted to better assess the efficacy and safety of this strategy in patients with early breast cancer. Methods The trials in which premenopausal women with early breast cancer were randomly assigned to receive (neo)adjuvant chemotherapy alone or with concurrent GnRHa were eligible for inclusion. Primary end points were premature ovarian insufficiency (POI) rate and post-treatment pregnancy rate. Disease-free survival and overall survival were secondary end points. Because each study represents a cluster, statistical analyses were performed using a random effects model. Results A total of 873 patients from five trials were included. POI rate was 14.1% in the GnRHa group and 30.9% in the control group (adjusted odds ratio, 0.38; 95% CI, 0.26 to 0.57; P, .001). A total of 37 (10.3%) patients had at least one post-treatment pregnancy in the GnRHa group and 20 (5.5%) in the control group (incidence rate ratio, 1.83; 95% CI, 1.06 to 3.15; P = .030). No significant differences in disease-free survival (adjusted hazard ratio, 1.01; 95% CI, 0.72 to 1.42; P = .999) and overall survival (adjusted hazard ratio, 0.67; 95% CI, 0.42 to 1.06; P = .083) were observed between groups. Conclusion Our findings provide evidence for the efficacy and safety of temporary ovarian suppression with GnRHa during chemotherapy as an available option to reduce the likelihood of chemotherapy-induced POI and potentially improve future fertility in premenopausal patients with early breast cancer

    STAT3 regulated ARF expression suppresses prostate cancer metastasis.

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    Prostate cancer (PCa) is the most prevalent cancer in men. Hyperactive STAT3 is thought to be oncogenic in PCa. However, targeting of the IL-6/STAT3 axis in PCa patients has failed to provide therapeutic benefit. Here we show that genetic inactivation of Stat3 or IL-6 signalling in a Pten-deficient PCa mouse model accelerates cancer progression leading to metastasis. Mechanistically, we identify p19(ARF) as a direct Stat3 target. Loss of Stat3 signalling disrupts the ARF-Mdm2-p53 tumour suppressor axis bypassing senescence. Strikingly, we also identify STAT3 and CDKN2A mutations in primary human PCa. STAT3 and CDKN2A deletions co-occurred with high frequency in PCa metastases. In accordance, loss of STAT3 and p14(ARF) expression in patient tumours correlates with increased risk of disease recurrence and metastatic PCa. Thus, STAT3 and ARF may be prognostic markers to stratify high from low risk PCa patients. Our findings challenge the current discussion on therapeutic benefit or risk of IL-6/STAT3 inhibition.Lukas Kenner and Jan Pencik are supported by FWF, P26011 and the Genome Research-Austria project “Inflammobiota” grants. Helmut Dolznig is supported by the Herzfelder Family Foundation and the Niederösterr. Forschungs-und Bildungsges.m.b.H (nfb). Richard Moriggl is supported by grant SFB-F2807 and SFB-F4707 from the Austrian Science Fund (FWF), Ali Moazzami is supported by Infrastructure for biosciences-Strategic fund, SciLifeLab and Formas, Zoran Culig is supported by FWF, P24428, Athena Chalaris and Stefan Rose-John are supported by the Deutsche Forschungsgemeinschaft (Grant SFB 877, Project A1and the Cluster of Excellence --“Inflammation at Interfaces”). Work of the Aberger lab was supported by the Austrian Science Fund FWF (Projects P25629 and W1213), the European FP7 Marie-Curie Initial Training Network HEALING and the priority program Biosciences and Health of the Paris-Lodron University of Salzburg. Valeria Poli is supported by the Italian Association for Cancer Research (AIRC, No IG13009). Richard Kennedy and Steven Walker are supported by the McClay Foundation and the Movember Centre of Excellence (PC-UK and Movember). Gerda Egger is supported by FWF, P27616. Tim Malcolm and Suzanne Turner are supported by Leukaemia and Lymphoma Research.This is the final version of the article. It first appeared from Nature Publishing Group via http://dx.doi.org/10.1038/ncomms873

    Highlights from the Pierre Auger Observatory

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    The Pierre Auger Observatory is the world's largest cosmic ray observatory. Our current exposure reaches nearly 40,000 km2^2 str and provides us with an unprecedented quality data set. The performance and stability of the detectors and their enhancements are described. Data analyses have led to a number of major breakthroughs. Among these we discuss the energy spectrum and the searches for large-scale anisotropies. We present analyses of our Xmax_{max} data and show how it can be interpreted in terms of mass composition. We also describe some new analyses that extract mass sensitive parameters from the 100% duty cycle SD data. A coherent interpretation of all these recent results opens new directions. The consequences regarding the cosmic ray composition and the properties of UHECR sources are briefly discussed.Comment: 9 pages, 12 figures, talk given at the 33rd International Cosmic Ray Conference, Rio de Janeiro 201

    Failure to detect Plasmodium vivax in West and Central Africa by PCR species typing

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    <p>Abstract</p> <p>Background</p> <p><it>Plasmodium vivax </it>is estimated to affect 75 million people annually. It is reportedly absent, however, from west and central Africa due to the high prevalence of the Duffy negative phenotype in the indigenous populations. Despite this, non-African travellers consistently return to their own countries with <it>P. vivax </it>malaria after visiting this region. An attempt was made, therefore, to detect the presence of <it>P. vivax </it>parasites in blood samples collected from the indigenous populations of west and central Africa.</p> <p>Methods</p> <p>Parasite species typing (for all four human malaria parasites) was carried out by PCR on 2,588 blood samples collected from individuals from nine African malaria-endemic countries.</p> <p>Results</p> <p>Most infections (98.5%) were <it>Plasmodium falciparum</it>, <it>Plasmodium malariae </it>was identified in 8.5% of all infections, and <it>Plasmodium ovale </it>in 3.9%. The prevalence of both parasites varied greatly by country. Only one case of <it>P. vivax </it>was detected from Sao Tome, an island off the west coast of Africa, confirming the scarcity of this parasite in Africa.</p> <p>Conclusion</p> <p>The prevalence of <it>P. vivax </it>in local populations in sub-Saharan Africa is very low, despite the frequent identification of this parasite in non-African travellers.</p
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