Feeding ecology and seed dispersal of pigtail macaques (Macaca nemestrina) in Khao Yai National Park, Thailand

peer reviewedSeed dispersal has a profound influence on structure and diversity in tropical environment. Although all frugivorous primates disperse seeds, the contribution of dispersal by some species in forest regeneration is still discussed. For instance, baboons and macaques are controversially described as seed dispersers or as seed predators. We study the seed dispersal by a troop of pigtail macaques (Macaca nemestrina leonina) in the Khao Yai National Park (Thailand) in order to describe the mode of seed dispersal and the seed fate of each fruit species consumed by macaques, including the assessment of potential germination enhancement for dispersed seeds. Pigtail macaques disperse seeds either via feces, by swallowing seeds, or via cheekpouch storage, by spitting out seeds after processing the fruits in the mouth. Preliminary results of our study show that pigtail macaques in the study troop disperse the seeds of at least 15 fruits species. For some species (Nephelium melliferum, Baccaurea ramiflora), macaques use the 2 modes of seed dispersal simultaneously. If part of the seeds excreted are intact and viable, as shown by the cut test, some are destroyed during mastication and digestion, and therefore it seems that macaques are to be considered both as seed dispersers and predators. The size of dispersed seeds ranges from the largest defecated seed (Nephelium melliferum) of 22mm long and 13mm wide to the smallest (Dissocheta divaricata) less than 1mm long and 0.5mm wide. In the future, Tetrazolium test will also be used to assess seed viability, and the germination enhancement for seeds defecated or spat out will be assessed using germination test. Germination rate and germination delay will be compared for defecated, spat and control (seeds from non consumed fruits collected from trees foraged by the macaques) seeds

Mott scattering of polarized electrons in a strong laser field

We present analytical and numerical results of the relativistic calculation of the transition matrix element $S_{fi}$ and differential cross section for Mott scattering of initially polarized Dirac particles (electrons) in the presence of strong laser field with linear polarization. We use exact Dirac-Volkov wave functions to describe the dressed electrons and the collision process is treated in the first Born approximation. The influence of the laser field on the degree of polarization of the scattered electron is reported.Comment: 12 pages, 11 figures, Revte

Co-evolution of the parasitic fungi Pneumocystis and their Muridae rodent hosts in Southeast Asia

Pneumocystis species are opportunistic and airborne-transmitted fungi that infect the lungs of numerous mammalian species. These highly diversified fungi are characterized by strong host specificity, probably associated with co-speciation. In this study, we investigate the Pneumocystis genetic diversity and infection rate in Muridae rodents of Southeast Asia in relation to environmental habitats. A total of 445 wild rodents belonging to 18 Southeast Asian Muridae species were tested for the presence of Pneumocystis in their lungs through PCR amplification of two Pneumocystis mitochondrial genes (mtLSU rRNA and mtSSU rRNA). Pneumocystis DNA was detected in 215 (48.3%) out of these 445 rodents. Eight highly divergent Pneumocystis lineages were retrieved in our phylogenetic tree. Three of these lineages correspond to the described species Pneumocystis murina (infecting Mus species), P. carinii (infecting Rattus species) and P. wakefieldiae (also infecting Rattus species). Three individuals belonging to Rattus norvegicus were found co-infected by both P. carinii and P. wakefieldiae. The five remaining lineages may correspond to several new undescribed Pneumocystis species and infect the lungs of Cannomys (lineage 1), Bandicota (lineage 2), Berylmys (lineage 3), Rattus (lineage 4) and Maxomys, Niviventer and Leopoldamys (lineage 5) Muridae genera. The congruence between phylogenies of Pneumocystis and their rodent hosts has been tested using co-phylogenetic analyses and the number of inferred co-speciation events is significantly greater than expected by chance. Rodent species, age and sex have no influence on the Pneumocystis infection rate among Muridae rodents but individuals trapped close to human settlements in patchy habitat were more likely infected by Pneumocystis parasites

Computation of multiple eigenvalues and generalized eigenvectors for matrices dependent on parameters

The paper develops Newton's method of finding multiple eigenvalues with one Jordan block and corresponding generalized eigenvectors for matrices dependent on parameters. It computes the nearest value of a parameter vector with a matrix having a multiple eigenvalue of given multiplicity. The method also works in the whole matrix space (in the absence of parameters). The approach is based on the versal deformation theory for matrices. Numerical examples are given. The implementation of the method in MATLAB code is available.Comment: 19 pages, 3 figure

Spin dynamics of wave packets evolving with the Dirac Hamiltonian in atoms with high Z

The motion of circular WP for one electron in central Coulomb field with high Z is calculated. The WP is defined in terms of solutions of the Dirac equation in order to take into account all possible relevant effects in particular the spin-orbit potential. A time scale is defined within which spin dynamics must be taken into account mainly in the atoms with high Z. Within this time scale there exists a mechanism of collapses and revivals of the spin already shown by the authors for harmonic oscillator potential and called the 'spin-orbit pendulum'. However this effect has not the exact periodicity of the simpler model, but the WP's spatial motion is nevertheless quite similar.Comment: 17 pages, 9 figures, LaTeX2e, uses IOP style files (included). Title changed, one reference adde

On the absence of bound-state stabilization through short ultra-intense fields

We address the question of whether atomic bound states begin to stabilize in the short ultra-intense field limit. We provide a general theory of ionization probability and investigate its gauge invariance. For a wide range of potentials we find an upper and lower bound by non-perturbative methods, which clearly exclude the possibility that the ultra intense field might have a stabilizing effect on the atom. For short pulses we find almost complete ionization as the field strength increases.Comment: 34 pages Late

On the Influence of Pulse Shapes on Ionization Probability

We investigate analytical expressions for the upper and lower bounds for the ionization probability through ultra-intense shortly pulsed laser radiation. We take several different pulse shapes into account, including in particular those with a smooth adiabatic turn-on and turn-off. For all situations for which our bounds are applicable we do not find any evidence for bound-state stabilization.Comment: 21 pages LateX, 10 figure

Ionization Probabilities through ultra-intense Fields in the extreme Limit

We continue our investigation concerning the question of whether atomic bound states begin to stabilize in the ultra-intense field limit. The pulses considered are essentially arbitrary, but we distinguish between three situations. First the total classical momentum transfer is non-vanishing, second not both the total classical momentum transfer and the total classical displacement are vanishing together with the requirement that the potential has a finite number of bound states and third both the total classical momentum transfer and the total classical displacement are vanishing. For the first two cases we rigorously prove, that the ionization probability tends to one when the amplitude of the pulse tends to infinity and the pulse shape remains fixed. In the third case the limit is strictly smaller than one. This case is also related to the high frequency limit considered by Gavrila et al.Comment: 16 pages LateX, 2 figure

Expanding the Taxonomy of (Mis-)Recognition in the Economic Sphere

This paper makes a contribution to debates in recognition theory by expanding the taxonomy of (mis-)recognition in the economic sphere. We argue that doing justice to the variety of ways in which recognition is engaged in economic relationships requires: (1) to take into consideration not just the recognition principle of esteem, but also (various aspects of) need and respect; (2) to distinguish a productive from a consumptive dimension with regards to each principle of recognition (need, esteem and respect); (3) and to identify the specific economic relationship at stake (e.g. between consumers and producers, or between employers and employees). In this way, we can account for the diversity of demands for recognition made in the economic sphere, explain what underpins them, and bring structure into these diverse phenomena. What is more, our expanded taxonomy is a useful tool for social pathology theorists. They have to appreciate the full range of variants of misrecognition when diagnosing pathologies of misrecognition in the economic sphere

Evolutionary history and species delimitations: a case study of the hazel dormouse, Muscardinus avellanarius

Robust identification of species and significant evolutionary units (ESUs) is essential to implement appropriate conservation strategies for endangered species. However, definitions of species or ESUs are numerous and sometimes controversial, which might lead to biased conclusions, with serious consequences for the management of endangered species. The hazel dormouse, an arboreal rodent of conservation concern throughout Europe is an ideal model species to investigate the relevance of species identification for conservation purposes. This species is a member of the Gliridae family, which is protected in Europe and seriously threatened in the northern part of its range. We assessed the extent of genetic subdivision in the hazel dormouse by sequencing one mitochondrial gene (cytb) and two nuclear genes (BFIBR, APOB) and genotyping 10 autosomal microsatellites. These data were analysed using a combination of phylogenetic analyses and species delimitation methods. Multilocus analyses revealed the presence of two genetically distinct lineages (approximately 11 % cytb genetic divergence, no nuclear alleles shared) for the hazel dormouse in Europe, which presumably diverged during the Late Miocene. The phylogenetic patterns suggests that Muscardinus avellanarius populations could be split into two cryptic species respectively distributed in western and central-eastern Europe and Anatolia. However, the comparison of several species definitions and methods estimated the number of species between 1 and 10. Our results revealed the difficulty in choosing and applying an appropriate criterion and markers to identify species and highlight the fact that consensus guidelines are essential for species delimitation in the future. In addition, this study contributes to a better knowledge about the evolutionary history of the species