Reunion overseas: introduced wild boars and cultivated orange trees interact in the Brazilian Atlantic forest

Little is known concerning novel interactions between species that typically interact in their native range but, as a consequence of human activity, are also interacting out of their original distribution under new ecological conditions. Objective: We investigate the interaction between the orange tree and wild boar, both of which share Asian origins and have been introduced to the Americas (i.e. the overseas). Methods: Specifically, we assessed whether i) wild boars consume orange (Citrus sinensis) fruits and seeds in orchards adjacent to a remnant of the Atlantic Forest of Brazil, ii) the orange seeds are viable after passing through boar’s digestive tract and iii) whether the orange tree may naturalise in the forest remnant assisted by wild boars. Results: Our camera surveys indicated that wild boar was by far the most frequent consumer of orange fruits (40.5 % of camera trap-days). A considerable proportion of sown orange seeds extracted from fresh boar feces emerged seedlings (27.8 %, N = 386) under controlled greenhouse conditions. Further, 37.6 % of sown seeds (N = 500) in the forest remnant emerged seedlings in July 2015; however, after ~4 years (March 2019) only 9 seedlings survived (i.e. 4.8 %, N = 188). Finally, 52 sweet orange seedlings were found during surveys within the forest remnant which is intensively used by wild boars. This study indicates a high potential of boars to act as effective seed dispersers of the sweet orange. However, harsh competition with native vegetation and the incidence of lethal diseases, which quickly kill sweet orange trees under non-agricultural conditions, could seriously limit orange tree establishment in the forest. Conclusions: Our results have important implications not only because the wild boar could be a vector of potential invasive species, but also because they disperse seeds of some native species (e.g. the queen palm, Syagrus romanzofiana) in defaunated forests, where large native seed dispersers are missing; thus, wild boars could exert critical ecological functions lost due to human activityinfo:eu-repo/semantics/publishedVersio

Nonuniversal dynamic conductance fluctuations in disordered systems

Sample-to-sample fluctuations of the time-dependent conductance of a system with static disorder have been studied by means of diagrammatic theory and microwave pulsed transmission measurements. The fluctuations of time-dependent conductance are not universal, i.e., depend on sample parameters, in contrast to the universal conductance fluctuations in the steady-state regime. The variance of normalized conductance, determined by the infinite-range intensity correlation C_3(t), is found to increase as a third power of delay time from an exciting pulse, t. C_3(t) grows larger than the long-range intensity correlation C_2(t) after a time t_q ~ ^{1/2} t_D (t_D being the diffusion time, being the average dimensionless conductance).Comment: Revised version, 6 pages, 5 figure

Ionic polaron in a Bose-Einstein condensate

The ground state properties of a degenerate bosonic gas doped with an ion are investigated by means of quantum Monte Carlo simulations in three dimensions. The system features competing length and energy scales, which result in vastly different polaronic properties compared to neutral quantum impurities. Depending on whether a two-body bound state is supported or not by the atom-ion potential, we identify a transition between a polaron regime amenable to a perturbative treatment in the limit of weak atom-ion interactions and a many-body bound state with vanishing quasi-particle residue composed of hundreds of atoms. In order to analyze the structure of the corresponding states we examine the atom-ion and atom-atom correlation functions. Our findings are directly relevant to experiments using hybrid atom-ion setups that have recently attained the ultracold regime.Comment: 11 pages, 6 figures, 1 tabl

A comparative study of hyperelastic constitutive models for colonic tissue fitted to multiaxial experimental testing

For colonic stents design, the interaction with colonic tissue is essential in order to characterize the appropriate radial stiffness which provides a minimum lumen for intestinal transit to be maintained. It is therefore important to develop suitable constitutive models allowing the mechanical behavior of the colon tissue to be characterized. The present work investigates the biomechanical behavior of colonic tissue by means of biaxial tests carried out on different parts of the colonic tract taken from several porcine specimens. Samples from the colonic tract were quasi-statically tensioned using a load-controlled protocol with different tension ratios between the circumferential and the axial directions. Fitting techniques were then used to adjust specific hyperelastic models accounting for the multilayered conformation of the colonic wall and the fiber-reinforced configuration of the corresponding tissues. It was found that the porcine colon changed from a more isotropic to a more anisotropic tissue and became progressively more flexible and compliant in circumferential direction depending on the position along the duct as it approaches the rectum. The best predictive capability of mechanical behavior corresponds to the Four Fiber Family model showing mean values of coefficient of determination R2 ¼ 0:97, and a normalized root mean square error of eNRMS ¼ 0:0814 for proximal spiral samples, and R2 ¼ 0:89 ; eNRMS ¼ 0:1600 and R2 ¼ 0:94 ; eNRMS ¼ 0:1227 for distal spiral and descending colon samples, respectively. The other analyzed models provide good results for proximal spiral colon specimens, which have a lower degree of anisotropy. The analyzed models with the fitted elastic parameters can be used for more realistic and reliable FE simulations, providing the appropriate framework for the design of optimal devices for the treatment of colonic diseases

Strong coupling Bose polarons in a two-dimensional gas

We study the properties of Bose polarons in two dimensions using quantum Monte Carlo techniques. Results for the binding energy, the effective mass, and the quasiparticle residue are reported for a typical strength of interactions in the gas and for a wide range of impurity-gas coupling strengths. A lower and an upper branch of the quasiparticle exist. The lower branch corresponds to an attractive polaron and spans from the regime of weak coupling where the impurity acts as a small density perturbation of the surrounding medium to deep bound states which involve many particles from the bath and extend as far as the healing length. The upper branch corresponds to an excited state where due to repulsion a low-density bubble forms around the impurity but might be unstable against decay into many-body bound states. Interaction effects strongly affect the quasiparticle properties of the polaron. In particular, in the strongly correlated regime, the impurity features a vanishing quasiparticle residue, signaling the transition from an almost free quasiparticle to a bound state involving many atoms from the bath.Comment: 8 pages, 5 figures

What's wrong with this rebuttal?

A recent rebuttal to criticism of Bell's analysis is shown to be defective by fault of failure to consider all hypothetical conditions input into the derivation of Bell Inequalitites.Comment: 2 page