bluuebunny/crossref_metadata_2025_split huggingface dataset:
FAIR VALUATION OF INSURANCE LIABILITY CASH-FLOW STREAMS IN CONTINUOUS TIME: APPLICATIONS
Authors: Delong Łukasz , Dhaene Jan , Barigou Karim 
Published: April 2019

AbstractDelong et al. (2018) presented a theory of fair (market-consistent and actuarial) valuation of insurance liability cash-flow streams in continuous time. In this paper, we investigate in detail two practical applications of our theory of fair valuation. In the first example, we consider the fair valuation of a terminal benefit which is contingent on correlated tradeable and non-tradeable financial risks. In the second example, we consider a portfolio of unit-linked contracts contingent on a non-tradeable insurance and a tradeable financial risk. We derive partial differential equations (PDEs) which characterize the continuous-time fair valuation operators in these two examples and we find explicit solutions to these PDEs. The fair values of the liabilities are decomposed into the best estimate of the liability and a risk margin. The arbitrage-free representations of the fair values of the liabilities are derived and the dynamic hedging strategies associated with the continuous-time fair valuation operators are also established. Detailed interpretations of the results, which should be useful both for researchers and practitioners, are provided.
Under the Influence: Pay-Offs to Legislative Support Parties under Minority Governments
Authors: Anghel Veronica , Thürk Maria 
Published: April 2019

AbstractPrevious studies show that in multiparty systems the formation of minority governments can be a rational choice. To ensure survival and policy implementation, minority governments make concessions to non-cabinet parties. In this study, we empirically analyse the pay-offs given to support parties under minority governments. We argue that the content of support agreements is conditioned by support party type. Results are based on a two-stage empirical investigation: a text analysis of 10 explicit support arrangements for minority governments in Romania and a within-case comparison of two Romanian minority cabinets with different support arrangements. We employ an original data set of support agreements and elite interviews with former minority cabinet members. We empirically confirm that ethno-regional parties are mostly policy-seeking and target benefits for their specific groups. In contrast, mainstream parties make stronger claims for office distribution. The analysis challenges the widespread understanding that all support parties are mostly policy-seeking.
Connecting the ISM to TeV PWNe and PWN candidates
Authors: Voisin F. J. , Rowell G. P. , Burton M. G. , Fukui Y. , Sano H. , Aharonian F. , Maxted N. , Braiding C. , Blackwell R. , Lau J. 
Published: April 2019

AbstractWe investigate the interstellar medium towards seven TeV gamma-ray sources thought to be pulsar wind nebulae using Mopra molecular line observations at 7 mm [CS(1–0), SiO(1–0, v = 0)], Nanten CO(1–0) data and the Southern Galactic Plane Survey/GASS Hisurvey. We have discovered several dense molecular clouds co-located to these TeV gamma-ray sources, which allows us to search for cosmic rays coming from progenitor SNRs or, potentially, from pulsar wind nebulae. We notably found SiO(1–0, v = 0) emission towards HESS J1809–193, highlighting possible interaction between the adjacent supernova remnant SNR G011.0–0.0 and the molecular cloud atd∼ 3.7 kpc. Using morphological features, and comparative studies of our column densities with those obtained from X-ray measurements, we claim a distanced∼ 8.6 − 9.7kpc for SNR G292.2–00.5,d∼ 3.5 − 5.6 kpc for PSR J1418–6058 andd∼ 1.5 kpc for the new SNR candidate found towards HESS J1303–631. From our mass and density estimates of selected molecular clouds, we discuss signatures of hadronic/leptonic components from pulsar wind nebulae and their progenitor SNRs. Interestingly, the molecular gas, which overlaps HESS J1026–582 atd∼ 5 kpc, may support a hadronic origin. We find however that this scenario requires an undetected cosmic-ray accelerator to be located atd< 10 pc from the molecular cloud. For HESS J1809–193, the cosmic rays which have escaped SNR G011.0–0.0 could contribute to the TeV gamma-ray emission. Finally, from the hypothesis that at most 20% the pulsar spin down power could be converted into CRs, we find that among the studied pulsar wind nebulae, only those from PSR J1809–1917 could potentially contribute to the TeV emission.
The diagnostic utility of sequence-based assays for the molecular delimitation of the epidemiologically relevantCulex pipiens pipienstaxa (Diptera: Culicidae)
Authors: Francuski L. , Gojković N. , Krtinić B. , Milankov V. 
Published: April 2019

AbstractThe northern house mosquito (Culex pipiens pipiensL.) is a vector of several important pathogens and comprises two epidemiologically distinct ecotypes (molestusForskål andpipiens). The delimitation of its ecotypes is a crucial, yet controversial step in vector surveillance due to varying diagnostic values of different characters. Therefore, we reviewed the success of a diagnostic assay based on the mitochondrial cytochromecoxidase subunit I locus (COI) by analyzing previously published sequences ofmolestusandpipienssampled in different geographical areas. Next, by genotyping individuals from Northern Serbia at this locus, we additionally assessed whether genetic structure of urban and ruralCx. p. pipiensecotypes corresponded to the admixture pattern. Finally, to account for the different susceptibility of genetic markers to introgression, we also analyzed genetic structuring based on the ribosomal internal transcribed spacer 2 (ITS2). No latitude-dependent differentiation ofCx. p. pipiensecotypes was found at a global level, with theCOIassay further failing to accurately identifymolestusandpipiensecotypes. Likewise, both individual- (BAPS) and population-based (analysis of molecular variance andFSTestimates) methods showed no significant urban/rural genetic differentiation in Serbia, indicating unhindered gene flow between differentCx. p. pipienshabitat types. The findings challenge the previous instances ofCx. p. pipiensecotype identification, while also spotlighting the vectorial capacity of their hybrid offspring.
Pest kill rate as aggregate evaluation criterion to rank biological control agents: a case study with Neotropical predators of Tuta absoluta on tomato
Authors: van Lenteren J.C. , Bueno V.H.P. , Burgio G. , Lanzoni A. , Montes F.C. , Silva D.B. , de Jong P.W. , Hemerik L. 
Published: April 2019

AbstractTuta absoluta (Meyrick), a key pest of tomato, is quickly spreading over the world and biological control is considered as one of the control options. Worldwide more than 160 species of natural enemies are associated with this pest, and an important challenge is to quickly find an effective biocontrol agent from this pool of candidate species. Evaluation criteria for control agents are presented, with the advantages they offer for separating potentially useful natural enemies from less promising ones. Next, an aggregate parameter for ranking agents is proposed: the pest kill rate km. We explain why the predator's intrinsic rate of increase cannot be used for comparing the control potential of predators or parasitoids, while km can be used to compare both types of natural enemies. As an example, kill rates for males, females and both sexes combined of three Neotropical mirid species (Campyloneuropsis infumatus (Carvalho), Engytatus varians (Distant) and Macrolophus basicornis (Stål)) were determined, taking all life-history data (developmental times, survival rates, total nymphal and adult predation, sex ratios and adult lifespan) into account. Based on the value for the intrinsic rate of increase (rm) for T. absoluta and for the kill rate km of the predators, we predict that all three predators are potentially able to control the pest, because their km values are all higher than the rm of the pest. Using only km values, we conclude that E. varians is the best candidate for control of T. absoluta on tomato, with C. infumatus ranking second and M. basicornis last.
Production of alarm pheromone starts at embryo stage and is modulated by rearing conditions and farnesyl diphosphate synthase genes in the bird cherry-oat aphid Rhopalosiphum padi
Authors: Sun C.-X. , Li Z.-X. 
Published: April 2019

AbstractThe major component of aphid alarm pheromone is (E)-β-farnesene (EβF), but the molecular mechanisms of EβF synthesis are poorly understood. Here we established a biological model to study the modulation of EβF synthesis in the bird cherry-oat aphid Rhopalosiphum padi by using quantitative polymerase chain reaction, gas chromatography/mass spectrometry and RNA interference. Our results showed that the rearing conditions significantly affected the weight of adult and modulated EβF synthesis in a transgenerational manner. Specifically, the quantity of EβF per milligram of aphid was significantly reduced in the individually reared adult or 1st-instar nymphs derived from 1-day-old adult reared individually, but EβF in the nymph derived from 2-day-old adult that experienced collective conditions returned to normal. Further study revealed that the production of EβF started in embryo and was extended to early nymphal stage, which was modulated by farnesyl diphosphate synthase genes (RpFPPS1 and RpFPPS2) and rearing conditions. Knockdown of RpFPPS1 and RpFPPS2 confirmed the role played by FPPS in the biosynthesis of aphid alarm pheromone. Our results suggested that the production of EβF starts at the embryo stage and is modulated by FPPS and rearing conditions in R. padi, which sheds lights on the modulatory mechanisms of EβF in the aphid.
Butyric acid as a promising alternative to antibiotic growth promoters in broiler chicken production
Authors: Raza M. , Biswas A. , Mir N. A. , Mandal A. B. 
Published: April 2019

AbstractThe current work studied the effects of butyric acid (BA) supplementation on the growth performance, carcase characteristics, immunity, gut histology and serum biochemistry of broiler chicken. Four experimental diets were formulated: control, 20 mg bacitracin methylene di-salicylate/kg diet (BMD-supplemented), 3 g BA/kg diet and 4 g BA/kg diet. The results revealed higher body weight gain (BWG) in BA and BMD-supplemented groups. Only BMD supplementation increased the feed intake (FI) of birds, whereas BA supplementation improved feed efficiency. Expression of glucose transporter (GLUT5), sodium-dependent glucose transporter (SGLT1) and peptide transporter (PepT1) were up-regulated due to BMD and BA supplementation. However, at 21 days post-hatching SGLT1 expression in the BMD-supplemented group was down-regulated with respect to the BA-supplemented groups. The 4 g BA/kg diet yielded better humoral and cell-mediated immune responses than the other groups. No dietary effects were observed on carcase characteristics and histomorphometry of jejunum at 7 days post-hatching. However, at 42 days old, the 4 g BA/kg diet increased villus length and width significantly. There was a significant increase in serum protein, albumin, creatinine, aspartate aminotransaminase (AST), phosphorus and calcium due to BA supplementation. However, the reverse trend was observed in serum uric acid and cholesterol, where BA supplementation decreased both and BMD supplementation decreased uric acid levels only. Based on the results it was concluded that 4 g BA/kg diet supplementation in feed is optimal for desirable broiler production.
Anatomical variation of the sphenoid sinus in paediatric patients and its association with age and chronic rhinosinusitis
Authors: Odat H , Almardeeni D , Tanash M , Al-Qudah M 
Published: April 2019

AbstractObjectiveTo report the prevalence of different anatomical variations of the sphenoid sinus and its related structures among paediatric patients with or without chronic rhinosinusitis.MethodsComputed tomography scans of 50 paediatric patients with chronic rhinosinusitis were reviewed and compared to 50 scans of paediatric patients without chronic rhinosinusitis. The type of sphenoid sinus pneumatisation and the surrounding structures were thoroughly analysed. The patients were divided into three groups according to age.ResultsMean age was 10.9 years (range, 4–16 years). The sellar configuration was the commonest in all groups, while the conchal type was the least common. There were significant differences between paediatric patients with or without sinusitis in: sphenoid sinus pneumatisation type, vidian canal type and Onodi cell presence. In addition, there were significant differences between age groups in: sphenoid sinus pneumatisation type, single sinus septum and multiple septa presence, and internal carotid artery bulging.ConclusionAge and sinusitis have a significant impact on sphenoid pneumatisation type and surrounding structure variation. Recognition of these variations can be useful for mapping this region, and enables a safer and more efficient endoscopic surgical procedure.
Endoscopic septoplasty: literature review, surgical techniques and retrospective analysis at the University Hospitals Leuven
Authors: Vandenbroeck S , Jorissen M 
Published: April 2019

AbstractBackgroundEndoscopic septoplasty is an alternative approach for a deviated nasal septum. Since its introduction, numerous techniques have been developed, each with its own advantages and limitations. A literature review is presented, along with our experience with endoscopic spur resection.MethodsThe Medline and Google Scholar databases were searched for relevant literature, and the records of all patients undergoing endoscopic spur resection at the University Hospitals Leuven between 2001 and 2015 were reviewed.Results and conclusionEndoscopic septoplasty offers improved visualisation and the option of limited flap dissection, which are particularly helpful when dealing with isolated spurs, posterior deviations and revision septoplasty. It enhances teaching and improves surgical transition to endoscopic sinus surgery. Reported success and complication rates are comparable to those seen in traditional approaches. Endoscopic spur resection, as conducted at the University Hospitals Leuven, was shown to be a quick, safe and efficient technique when dealing with isolated septal spurs, especially when combined with endoscopic sinus surgery.
Revisiting ADHD age-of-onset in adults: to what extent should we rely on the recall of childhood symptoms?
Authors: Breda V. , Rohde L. A. , Menezes A. M. B. , Anselmi L. , Caye A. , Rovaris D. L. , Vitola E. S. , Bau C. H. D. , Grevet E. H. 
Published: April 2019

AbstractBackgroundADHD diagnosis requires the presence of symptoms before the age of twelve. In clinical assessment of adults, the most frequent strategy to check this criterion is investigating self-report recall of symptoms, despite little evidence on the validity of this approach. We aim to evaluate the recall accuracy and factors associated with its reliability in a large population-based sample of adults.MethodsIndividuals from the 1993 Pelotas Birth Cohort were followed-up from childhood to adulthood. At the age of 22, 3810 individuals were assessed through structured interviews by trained psychologists regarding mental health outcomes, including ADHD diagnosis and ADHD symptoms in childhood. The retrospective recall was compared with available information on ADHD childhood symptoms at the age of eleven. We also assessed factors related to recall accuracy through multiple regression analyses.ResultsSelf-reported recall of childhood symptoms at 22 years of age had an accuracy of only 55.4%, with sensitivity of 32.8% and positive predictive value of 40.7%. Current inattention symptoms were associated with lower risk and social phobia with higher risk for false-positive endorsement, while higher levels of schooling correlated with lower risk and male gender with higher risk for false-negative endorsement.ConclusionsClinicians treating male patients with social phobia and ADHD symptoms should assess even more carefully retrospective recall of ADHD childhood symptoms. Moreover, characteristics associated with recall improvement do not impact accuracy robustly. In this context, the recall of childhood ADHD symptoms seems an unreliable method to characterize the neurodevelopmental trajectory in adults with currently-impairing ADHD symptomatology.
Influence of backstreaming ions on spot size of 2 MeV electron beam
Authors: Trunev Yury , Skovorodin Dmitry , Astrelin Vitaly , Danilov Valerii , Burdakov Alexander , Kurkuchekov Victor , Popov Sergey , Sinitsky Stanislav , Tarakanov Vladimir , Atlukhanov Magomedriza 
Published: April 2019

AbstractInfluence of backstreaming ions from the target on spot size of focused 2 MeV electron beam was considered. The 2D version of the particle-in-cell code KARAT was used to study the formation of the ions stream and dynamics of the electron beam. It was shown that light species emitted from the target can disrupt the beam. The emission of low-ionized states of tantalum cannot disrupt the beam during about 30 ns or longer. A few non-invasive techniques of mitigation of the beam disruption were considered. Final magnetic lens with fast variation of magnetic field of several hundred Ampere-turns per nanosecond is capable to stabilize initial spot size of the compressed beam at the target.
Adaptation Mechanism of Asymmetrical Potential Field Improving Precision of Position Tracking in the Case of Nonholonomic UAVs
Authors: Kownacki Cezary , Ambroziak Leszek 
Published: April 2019

SummaryPosition-tracking problems in the structures of rigid formations of nonholonomic mobile robots, such as fixed-wing unmanned aerial vehicle (UAVs), must reconcile tracking precision and flight stability, which usually exclude each other due to nonholonomic motion constraints. Therefore, a position-tracking control that is based on distance and position displacement, defined as inputs of control loops, requires the application of dead zones around target positions, which are the points of instability. For this reason, the control becomes sensitive to any external disturbance causing oscillations of control signals and so it becomes difficult to maintain a zero value of position displacement over a long time horizon. Thus, we propose an approach based on the adaptive mechanism of an asymmetrical local artificial potential field, which is defined by a local frame of reference whose origin is located in the tracked position of a UAV in the formation frame. It couples controls of both airspeed and heading angle into a nonlinear potential function of relative position and orientation with respect to the tracked position and adapts it according to heading rate of the leader. The function splits the area around the tracked position longitudinally into two zones of acceleration and deceleration; therefore, velocity vectors are longer (higher airspeed) only when a UAV is behind the tracked position and shorter (lower airspeed) when it is ahead. The area is laterally symmetrical, and orientations of velocity vectors align asymptotically to the longitudinal direction accordingly with the decrease in the lateral error. Finally, velocity vectors are rotated proportionally to the heading rate of the leader, which improves the tracking precision during turns. If we assumed that a UAV’s tracked position is in motion, it could easily be proven that the position control based on the adaptive asymmetrical potential function becomes asymptotically stable in the tracked position. Numerical simulation verifies this thesis and presents more precise and stable position tracking due to the adaptation mechanism.
Adaptive Neural Feedback Linearizing Control of Type (m,s) Mobile Manipulators with a Guaranteed Prescribed Performance
Authors: Shojaei Khoshnam , Kazemy Ali 
Published: April 2019

SummaryIn this paper, a neural network (NN)-based tracking controller is proposed for a general class of type (m,s) wheeled mobile manipulators (WMMs) subjected to model uncertainties with prescribed transient and steady-state performance specifications. First, an input–output model of WMMs is derived by introducing proper output equations. Then, the prescribed performance technique is employed to propose a proportional integral derivative trajectory tracking controller for WMMs to ensure that the tracking errors converge to a smaller, arbitrary ultimate bound with a predefined maximum overshoot/undershoot and convergence speed. The learning capabilities of multilayer NNs are incorporated into the controller to approximate the uncertain nonlinear dynamics of the robot. An adaptive saturation-type controller is utilized to compensate NN estimation errors and external disturbances. A Lyapunov-based stability analysis is used to demonstrate that the tracking errors are uniformly ultimately bounded and converge to a small neighborhood of zero with a guaranteed prescribed performance. Numerical computer simulations are presented to show the effectiveness of the proposed controller.
Design and Development of a Novel 2-Degree-of-Freedom Parallel Robot
Authors: Cheng Changxi , Huang Wenkai , Zhang Chunliang 
Published: April 2019

SummaryParallel robots are widely used in the fields of manufacturing, medical science, education, scientific research, etc. Many studies have been conducted on the topic already. However, shortcomings still exist, especially in certain situations. To meet the demand of good speed and load performances at the same time, this work presents a novel 2-degree-of-freedom parallel robot. The structural design, static, stiffness, and reachable workspace analysis of the robot are given in the manuscript. Experiment regarding the accuracy and speed performance is conducted, and the results are provided. In the end, potential applications of the proposed robot are suggested.
Symmetric quotients of knot groups and a filtration of the Gordian graph
Authors: BAADER SEBASTIAN , KJUCHUKOVA ALEXANDRA 
Published: April 2019

AbstractWe define a metric filtration of the Gordian graph by an infinite family of 1-dense subgraphs. The nth subgraph of this family is generated by all knots whose fundamental groups surject to a symmetric group with parameter at least n, where all meridians are mapped to transpositions. Incidentally, we verify the Meridional Rank Conjecture for a family of knots with unknotting number one yet arbitrarily high bridge number.
Breeding success and population growth of Southern Ground Hornbills Bucorvus leadbeateri in an area supplemented with nest-boxes
Authors: CARSTENS KATE F. , KASSANJEE RESHMA , LITTLE ROB M. , RYAN PETER G. , HOCKEY PHIL A. R. 
Published: April 2019

SummaryThe provision of artificial nests can improve the conservation status of threatened bird species that are limited by nest-site availability. The shortage of natural cavity nesting sites is one factor limiting the population growth of the Southern Ground Hornbill Bucorvus leadbeateri. In an 1,800 km2 study area in north-eastern South Africa, 31 wooden nest-boxes were installed during 2002–2015. We investigated the relationships between nests, as well as environmental and social factors, with breeding. Generalised linear mixed models were fitted to the observational data and identified positive relationships between breeding attempts and each of home range size and the previous year’s rainfall; as well as positive relationships between breeding success (amongst the groups that attempt breeding) and each of earlier breeding, nest height and thickness of the nest cavity wall. The provision of nest-boxes increased the number of breeding groups and although breeding success also increased initially, it later declined as the density of breeding groups increased above 20 groups. Although nest-boxes alone did not increase overall breeding success, they are an effective conservation tool to enhance the population of Southern Ground Hornbills if spaced optimally, to enhance reproductive output in areas where suitable nest-sites are scarce or lacking.