bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prey density affects predator foraging strategy in an Antarctic ecosystem
Authors: Busdieker Karl M. , Patrick Samantha C. , Trevail Alice M. , Descamps Sébastien 
Published: December 2019

AbstractStudying the effects of prey distribution on predator behavior is complex in systems where there are multiple prey species. The role of prey density in predator behavior is rarely studied in closed ecosystems of one predator species and one prey species, despite these being an ideal opportunity to test these hypotheses. In this study, we investigate the effect of prey density on the foraging behavior of a predatory species in an isolated Antarctic ecosystem of effectively a single predatory species and a single prey species. We use resource selection models to compare prey density in areas utilized by predators (obtained from fine‐scale GPS telemetry data) to prey density at randomly generated points (pseudoabsences) throughout the available area. We demonstrate that prey density of breeding Antarctic petrels (Thalassoica antarctica) is negatively associated with the probability of habitat use in its only predator, the south polar skua (Catharacta maccormicki). Skuas are less likely to utilize habitats with higher petrel densities, reducing predation in these areas, but these effects are present during chick rearing only and not during incubation. We suggest that this might be caused by successful group defense strategies employed by petrel chicks, primarily spitting oil at predators.
Difficulties in benchmarking ecological null models: an assessment of current methods
Authors: Molina Chai , Stone Lewi 
Published: December 2019

AbstractIdentifying species interactions and detecting when ecological communities are structured by them is an important problem in ecology and biogeography. Ecologists have developed specialized statistical hypothesis tests to detect patterns indicative of community‐wide processes in their field data. In this respect, null model approaches have proved particularly popular. The freedom allowed in choosing the null model and statistic to construct a hypothesis test leads to a proliferation of possible hypothesis tests from which ecologists can choose to detect these processes. Here, we point out some serious shortcomings of a popular approach to choosing the best hypothesis for the ecological problem at hand that involves benchmarking different hypothesis tests by assessing their performance on artificially constructed data sets. Terminological errors concerning the use of Type I and Type II errors that underlie these approaches are discussed. We argue that the key benchmarking methods proposed in the literature are not a sound guide for selecting null hypothesis tests, and further, that there is no simple way to benchmark null hypothesis tests. Surprisingly, the basic problems identified here do not appear to have been addressed previously, and these methods are still being used to develop and test new null models and summary statistics, from quantifying community structure (e.g., nestedness and modularity) to analyzing ecological networks.
Development of collapse‐consistent loading protocols for experimental testing of steel columns
Authors: Suzuki Yusuke , Lignos Dimitrios G. 
Published: December 2019

SummaryIn order to effectively utilize results from quasi‐static cyclic testing on structural components for the earthquake‐induced collapse risk quantification of structures, the need exists to establish collapse‐consistent loading protocols representing the asymmetric lateral drift demands of structures under low‐probability of occurrence earthquakes. This paper summarizes the development of such protocols for experimental testing of steel columns prone to inelastic local buckling. The protocols are fully defined with a deformation‐ and a force‐controlled parameter. They are generally applicable to quantify the capacity and demands of steel columns experiencing constant and variable axial load coupled with lateral drift demands. Through rigorous nonlinear earthquake collapse simulations, it is found that the building height, the column's local slenderness ratio, and ground motion type have the largest influence on the dual‐parameter loading protocol indexes. Comprehensive comparisons with measured data from full‐scale shake table collapse tests suggest that unlike routinely used symmetric cyclic loading histories, the proposed loading protocol provides sufficient information for modeling strength and stiffness deterioration in steel columns at large inelastic deformations.
Ambient vibration tools to validate the rigid diaphragm assumption in the seismic assessment of buildings
Authors: Sivori Daniele , Lepidi Marco , Cattari Serena 
Published: December 2019

SummaryVibration tests are encountering a growing success in earthquake engineering as a valuable tool for the seismic assessment of buildings. Ambient vibration measurements, in particular, offer reliable support for the updating of mechanical models, as well as the enhancement of seismic mitigation strategies for existing buildings. In this respect, the common description of the floor diaphragms as planar rigid bodies tends to oversimplify the actual mechanical behaviour of some traditional structural solutions, especially in masonry buildings. This assumption can be violated even in modern concrete and steel buildings due to inadequate design, poor manufacturing, or damage. The paper addresses the mathematical validation of the rigid diaphragm simplification using vibration measurements. To this purpose, a model‐based inverse kinematic problem is stated and solved to discriminate the in‐plane rigid motion and the angular deformation time histories from vibration data. Simple formulas, leveraging the approximate solution in the case of problem under‐determinacy, exploit the spectral content of vibration data to discuss the diaphragm deformability. Natural modes exhibiting different (rigid, quasi‐rigid, or nonrigid) diaphragm behaviour are distinguishable by comparing the power spectral densities of the rigid motion and angular deformation. Modes of pure floor deformability can also be identified. The influence of adverse testing conditions is discussed through pseudo‐experimental data simulating the dynamic response of a simple frame structure. As a complementary contribution, the procedure effectiveness is experimentally verified by analysing vibration data related to, first, laboratory tests on a scaled concrete‐steel frame and, finally, full‐scale tests on a masonry building.
Characteristics and clinical trajectories of patients meeting criteria for avoidant/restrictive food intake disorder that are subsequently reclassified as anorexia nervosa
Authors: Norris Mark L. , Santos Alexandre , Obeid Nicole , Hammond Nicole G. , Valois Darcie D. , Isserlin Leanna , Spettigue Wendy 
Published: December 2019

AbstractObjectiveTo examine the initial assessment profiles and early treatment trajectories of youth meeting the criteria for avoidant/restrictive food intake disorder (ARFID) that were subsequently reclassified as anorexia nervosa (AN).MethodA retrospective cohort study of patients assessed and treated in a tertiary care eating disorders (ED) program was completed.ResultsOf the 77 included patients initially meeting criteria for ARFID, six were reclassified as having AN (7.8%) at a median rate of 71 days after the first assessment. Patients in this cohort presented at very low % treatment goal weight (median 71.6%), self‐reported abbreviated length of illness (median 6 months), and exhibited low resting heart rates (median 46 beats per minute). Nutrition and feeding focused worries related more to general health as opposed to specific weight and shape concerns or fears at assessment in half of those reclassified with AN. Treatment at the 6‐month mark varied among patients, but comprised family and individual therapy, as well as prescription of psychotropic medication.ConclusionProspective longitudinal research that utilizes ARFID‐specific as well as traditional eating disorder diagnostic measures is required to better understand how patients with restrictive eating disorders that deny fear of weight gain can be differentiated and best treated.
State‐space models for predicting IBNR reserve in row‐wise ordered runoff triangles: Calendar year IBNR reserves & tail effects
Authors: Costa Leonardo , Pizzinga Adrian 
Published: December 2019

AbstractThe issue of modeling and forecasting IBNR (incurred but not reported) actuarial reserve under Kalman filter techniques and extensions, using data arranged in a runoff triangle, is a frequent theme in the literature. One quite recent approach is to order the runoff triangle under a row‐wise fashion and use linear state‐space models for the resulting data set. To allow new possibilities for short‐term IBNR reserves as well as to mitigate insolvency risk, in this paper we extend such a state‐space method by: (i) a calendar year IBNR reserve prediction; and (ii) a tail effect for the row‐wise ordered triangle. The extension is implemented with a real runoff triangle and compared with some traditional IBNR predictors. Empirical results indicate that the approach of this paper outperforms the competing methods in terms of out‐of‐sample comparisons and gives more conservative IBNR reserves than the original state‐space method.
Forecasting of dependence, market, and investment risks of a global index portfolio
Authors: Arreola Hernandez Jose , Al Janabi Mazin A.M. 
Published: December 2019

AbstractThis paper undertakes an in‐sample and rolling‐window comparative analysis of dependence, market, and portfolio investment risks on a 10‐year global index portfolio of developed, emerging, and commodity markets. We draw our empirical results by fitting vine copulas (e.g., r‐vines, c‐vines, d‐vines), IGARCH(1,1) RiskMetrics value‐at‐risk (VaR), and portfolio optimization methods based on risk measures such as the variance, conditional value‐at‐risk, conditional drawdown‐at‐risk, minimizing regret (Minimax), and mean absolute deviation. The empirical results indicate that all international indices tend to correlate strongly in the negative tail of the return distribution; however, emerging markets, relative to developed and commodity markets, exhibit greater dependence, market, and portfolio investment risks. The portfolio optimization shows a clear preference towards the gold commodity for investment, while Japan and Canada are found to have the highest and lowest market risk, respectively. The vine copula analysis identifies symmetry in the dependence dynamics of the global index portfolio modeled. Large VaR diversification benefits are produced at the 95% and 99% confidence levels by the modeled international index portfolio. The empirical results may appeal to international portfolio investors and risk managers for advanced portfolio management, hedging, and risk forecasting.
Alterations in genetic pathways following radiotherapy for head and neck cancer
Authors: Naghavi Arash O. , Kim Youngchul , Yang George Q. , Ahmed Kamran A. , Caudell Jimmy J. 
Published: December 2019

AbstractBackgroundRadiotherapy (RT) is an integral component in the treatment of head and neck cancer (HNC).We hypothesized there would be alterations in gene‐expression and pathway activity in HNC samples obtained in recurrent HNC that were previously treated with RT, when compared to RT‐naïve disease.MethodsPatient data was abstracted from a prospectively maintained database. Linear‐microarray analysis and supervised gene‐set enrichment‐analysis were employed to compare RT‐naive and recurrent disease after prior‐RT.ResultsA total of 157 patients were analyzed, 96 (61%) were RT‐naive and 61 (39%) had RT.After radiation, there was upregulation of genes associated with angiogenesis, protein‐translation‐machinery, cell‐cycle regulation, and growth factors, and downregulation associated with Myc activity, and hypoxic response (all P < .001).Previously irradiated HNC was associated with downregulation in 19/42 genes in the Wnt/B‐catenin‐pathway (P = .045)and 119/199 genes involved in the MYC target pathway (P = .024).ConclusionPatients with recurrences salvaged surgically post‐RT had significant alterations in gene‐expression and in Wnt/B‐catenin and MYC‐target pathways. These pathways may represent potential targets to prevent development of resistance to RT.
Variations in concerns reported on the patient concerns inventory in patients with head and neck cancer from different health settings across the world
Authors: Rogers Simon N. , Alvear Alvaro , Anesi Alexandre , Babin Emmanuel , Balik Ali , Batstone Martin , Brockmeyer Phillipp , Carrasco Claudia Celedon , Chien Chih‐Yen , Chirila Magdalena , Dholam Kanchan P. , Doss Jennifer G. , Finizia Caterina , Ghani Wan M. Nabilah , Gurav Sandeep V. , Kadir Kathreena , Kolator Mateusz , Lima Roberto , Lin Yu‐Tsai , Nhongo Simon , Ozdemir‐Karatas Meltem , Peker Kadriye , Pesic Zoran , Ransy Pierre , Santos Izabella , Schliephake Henning , Shah Ketan , Souza Fernanda , Sunil Geethu , Thankappan Krishnakumar , Ehrsson Ylva Tiblom , Tiple Cristina , Tuomi Lisa , Valerini Sara , Lara Pablo Vasquez , Zatoński Tomasz , Lowe Derek 
Published: December 2019

AbstractBackgroundThe aim was to collate and contrast patient concerns from a range of different head and neck cancer follow‐up clinics around the world. Also, we sought to explore the relationship, if any, between responses to the patient concerns inventory (PCI) and overall quality of life (QOL).MethodsNineteen units participated with intention of including 100 patients per site as close to a consecutive series as possible in order to minimize selection bias.ResultsThere were 2136 patients with a median total number of PCI items selected of 5 (2‐10). “Fear of the cancer returning” (39%) and “dry mouth” (37%) were most common. Twenty‐five percent (524) reported less than good QOL.ConclusionThere was considerable variation between units in the number of items selected and in overall QOL, even after allowing for case‐mix variables. There was a strong progressive association between the number of PCI items and QOL.
Onset of hypothyroidism after total laryngectomy: Effects of thyroid gland surgery and preoperative and postoperative radiotherapy
Authors: Plaat Robert E. , van Dijk Boukje A. C. , Muller Kobold Anneke C. , Steenbakkers Roel J. H. M. , Links Thera P. , van der Laan Bernard F. A. M. , Plaat Boudewijn E. C. 
Published: December 2019

AbstractBackgroundTo determine time of onset and risk of hypothyroidism after total laryngectomy (TL) with and without (hemi)thyroidectomy in relation to treatment regimen, that is, preoperative radiotherapy (RT‐TL), postoperative radiotherapy (TL‐RT), and postoperative re‐irradiation (RT‐TL‐RT).MethodsRetrospective review of 128 patients treated by RT‐TL (51 patients), TL‐RT (55 patients), and RT‐TL‐RT (22 patients). Risk of hypothyroidism was determined by multivariable Cox regression analysis and euthyroid survival was calculated using Kaplan‐Meier method.ResultsHypothyroidism developed in 69 (54%) patients. The median onset of hypothyroidism was later (P < .01) and the risk of hypothyroidism was lower (hazard ratio 0.49; P = .014) in the TL‐RT group compared to both other treatment regimens. Euthyroid survival did not differ between the treatment regimens. Two years euthyroid survival was 24% with and 61% without (hemi)thyroidectomy (P < .001).ConclusionsPatients treated with TL‐RT have later onset of hypothyroidism. Higher risk for hypothyroidism is associated with salvage TL after radiotherapy and (hemi)thyroidectomy.
Myeloproliferative and lymphoproliferative disorders: State of the art
Authors: Rumi Elisa , Baratè Claudia , Benevolo Giulia , Maffioli Margherita , Ricco Alessandra , Sant'Antonio Emanuela 
Published: December 2019

AbstractMyeloproliferative neoplasms (MPNs), including polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF), are clonal disorders complicated mainly by vascular events and transformation to myelofibrosis (for PV and ET) or leukemia. Although secondary malignancies, in particular, lymphoproliferative disorders (LPNs), are rare, they occur at a higher frequency than found in the general population, and there has been recent scientific discussion regarding a hypothetical relationship between treatment with JAK inhibitors in MPN and the risk of development of LPN. This has prompted increased interest regarding the coexistence of MPN and LPN. This review focuses on the role of JAK2 and the JAK/STAT pathway in MPN and LPN, whether there is a role for the genetic background in the occurrence of both MPN and LPN and whether there is a role for cytoreductive drugs in the occurrence of both MPN and LPN. Furthermore, whether an increased risk of lymphoma development is limited to patients who receive the JAK inhibitor ruxolitinib, is a more general phenomenon that occurs following JAK1/2 inhibition or is associated with preferential JAK1 or JAK2 targeting is discussed.
High intratumoural galectin‐1 expression predicts adverse outcome in ALK− ALCL and CD30+ PTCL‐NOS
Authors: Holst Johanne Marie , Ludvigsen Maja , Hamilton‐Dutoit Stephen Jacques , Bendix Knud , Plesner Trine Lindhardt , Nørgaard Peter , Møller Michael B. , Steiniche Torben , Rabinovich Gabriel A. , d'Amore Francesco , Pedersen Martin Bjerregård 
Published: December 2019

AbstractGalectin‐1 (Gal‐1) has been associated with adverse prognosis in several cancers including lymphoma entities with CD30 expression. However, Gal‐1 expression has not been systematically assessed in peripheral T‐cell lymphomas (PTCL). Specimens from 169 nodal PTCL were assessed for intratumoural Gal‐1 expression by immunohistochemistry. Overall survival (OS) in groups exhibiting high and low Gal‐1 expression was compared in the cohort and in a subset analysis of CD30‐positive PTCL only. Gal‐1 expression was also correlated with biomarkers of the tumour microenvironment. No significant difference in OS based on Gal‐1 expression was observed in the entire PTCL cohort. However, in the CD30‐positive cohort, patients with high Gal‐1 levels had significantly poorer outcome (5 years OS 10%, 95% confidence interval CI, 1‐36) than their low Gal‐1 counterparts (5 years OS 48%, 95% CI, 30‐64, P = .021). In univariate analyses age 60 or younger, non‐elevated lactate dehydrogenase (LDH), and performance score less than 2 correlated with superior survival but high Gal‐1 expression significantly predicted adverse outcome at both univariate (HR 2.5, 95% CI, 1.1‐5.7, P = .026) and multivariate levels (HR 3.2, 95% CI, 1.2‐8.5, P = .017). Tumours with high Gal‐1 had few cytotoxic T cells in the tumour microenvironment. High intratumoural Gal‐1 expression before therapeutic intervention correlates with adverse outcome in nodal CD30+, ALK− PTCL patients.
Chronic and episodic acidification of streams along the Appalachian Trail corridor, eastern United States
Authors: Burns Douglas A. , McDonnell Todd C. , Rice Karen C. , Lawrence Gregory B. , Sullivan Timothy J. 
Published: December 2019

AbstractAcidic atmospheric deposition has adversely affected aquatic ecosystems globally. As emissions and deposition of sulfur (S) and nitrogen (N) have declined in recent decades across North America and Europe, ecosystem recovery is evident in many surface waters. However, persistent chronic and episodic acidification remain important concerns in vulnerable regions. We evaluated acidification in 269 headwater streams during 2010–2012 along the Appalachian Trail (AT) that transits several ecoregions and is located downwind of high levels of S and N emission sources. Discharge was estimated by matching sampled streams to those of a nearby gaged stream and assuming equivalent daily mean flow percentiles. Charge balance acid‐neutralizing capacity (ANC) values were adjusted to the 15th (Q15) and 85th flow percentiles (Q85) by applying the ANC/discharge slope among sample pairs collected at each stream. A site‐based approach was applied to streams sampled twice or more and a second regression‐based approach to streams sampled once to estimate episodic acidification magnitudes as the ANC difference from Q15 to Q85. Streams with ANC <0 μeq/L doubled from 16% to 32% as discharge increased from Q15 to Q85 according to the site‐based approach. The proportion of streams with ANC <0 μeq/L at low flow and high flow decreased from north to south. Base cation dilution explained the greatest amount of episodic acidification among streams and variation in sulfate (SO42−) concentrations was a secondary explanatory variable. Episodic SO42− patterns varied geographically with dilution dominant in northern streams underlain by soils developed in glacial sediment and increased concentrations dominant in southern streams with older, highly weathered soils. Episodic acidification increased as low‐flow ANC increased, exceeding 90 μeq/L in 25% of streams. Episodic increases in ANC were the dominant pattern in streams with low‐flow ANC values <30 μeq/L. Chronic and episodic acidification remain an ecological concern among AT streams. The approach developed here could be applied to estimate the magnitude and extent of chronic and episodic acidification in other regions recovering from decreasing levels of atmospheric S and N deposition.
Can Life Emerge from Synthetic Polymers?
Authors: Lutz Jean‐François 
Published: December 2019

AbstractSynthetic chemistry has drastically progressed during the last few decades. Like in DNA, it is now possible to synthesize abiotic macromolecules with precisely‐controlled sequences of monomers. Artificial systems allowing hybridization and information transfer have been described. Simple metabolism models have also been prepared and investigated. Thus, the creation of minimal artificial life forms appears as a (still relatively far) but possibly reachable objective. In this context, the aim of the present essay is to discuss recent achievement and future challenges towards man‐induced abiogenesis. In terms of polymer design, a synthetic macromolecule that would support Life as DNA do would require at least all the following properties: (i) information‐storage capacity, (ii) information‐transfer ability and (iii) the possibility to evolve through molecular mutations. Recent advances in that direction are summarized herein. However, Life is not only a matter of macromolecular design. In order to operate, a self‐replicator shall co‐exist with other molecules in non‐equilibrium conditions. Hence, systems chemistry aspects are also discussed in this essay.
Fluorescent Reporters for Drug Delivery Monitoring
Authors: Patsenker Leonid , Gellerman Gary 
Published: December 2019

AbstractMonitoring of drug delivery is an essential technique for innovative medical treatments, including cancer therapy. Fluorescence imaging has become an important tool in tracking drug delivery and thus improving treatment efficacy. Binding fluorescent reporters to therapeutic agents paves the way to real time monitoring of drug delivery and drug distribution in vitro and in vivo. This review discusses fluorescent reporters used in drug delivery monitoring and provides an overview of recent achievements in the development of fluorescence based drug delivery systems.