A Novel Combined System of Direction Estimation and Sound Zooming of Multiple Speakers

This article presents a new system for estimation the direction of multiple speakers and zooming the sound of one of them at a time. The proposed system is a combination of two levels; namely, sound source direction estimation, and acoustic zooming. The sound source direction estimation uses so-called the energetic analysis method for estimation the direction of multiple speakers, whereas the acoustic zooming is based on modifying the parameters of the directional audio coding (DirAC) in order to zoom the sound of a selected speaker among the others. Both listening tests and objective assessments are performed to evaluate this system using different time-frequency transforms

Labor outcome among obese postdate women undergoing labor induction

Background: Maternal obesity and postdate pregnancy are common findings among pregnant women worldwide. We aimed to evaluate the influence of maternal obesity on the outcome of labor induction for postdate pregnant women.Methods: We conducted a prospective observational study to compare 118 obese women (≥30 kg/m2) with 118 non-obese women (<30 kg/m2) undergoing labor induction for postdate pregnancy (≥41 weeks). We induced all participants by a uniform protocol according to the Bishop score. The primary outcome measures were the cesarean delivery (CD) rate and the rate of failed induction. Secondary outcomes included prolonged induction- delivery time, prolonged first and second stage of labor, and rate of instrumental delivery. We performed a multivariate regression model to assess for the relation between obesity and the study outcomes of interest.Results: Cesarean delivery was significantly higher in obese women when compared with non-obese women (25.4% vs. 12.7%, p=0.02). Likewise, failed induction rate was significantly lower among non-obese women (5.1% vs. 14.4%. p=0.026). Obese women had increased odds for CD (adjusted odds ratio: 2.24; 95% confidence-interval: 1.13-4.33), failed induction rate (adjusted OR 2.96; 95% CI: 1.15-8.17), prolonged induction-delivery time (adjusted OR 4.57; 95% CI: 1.42-14.74), prolonged first stage of labor (adjusted OR 3.32; 95% CI: 1.07-9.89), prolonged second stage of labor (adjusted OR 4.21; 95% CI: 1.27-13.62), and rate of instrumental delivery (adjusted OR 2.97; 95% CI: 1.16-8.23).Conclusions: Obesity adds more risk to postdate women undergoing induction of labor. Obesity increases the incidence of CD and failed induction among induced postdate women. Therefore, obstetricians should encourage obese women to reduce weight before getting pregnant, and to comply with the optimal weight gain during pregnancy in attempt to reduce the rates of postdating, CD and failed induction

On Fermat's principle for causal curves in time oriented Finsler spacetimes

In this work, a version of Fermat's principle for causal curves with the same energy in time orientable Finsler spacetimes is proved. We calculate the secondvariation of the {\it time arrival functional} along a geodesic in terms of the index form associated with the Finsler spacetime Lagrangian. Then the character of the critical points of the time arrival functional is investigated and a Morse index theorem in the context of Finsler spacetime is presented.Comment: 20 pages, minor corrections, references adde

Homogeneous variational problems: a minicourse

A Finsler geometry may be understood as a homogeneous variational problem, where the Finsler function is the Lagrangian. The extremals in Finsler geometry are curves, but in more general variational problems we might consider extremal submanifolds of dimension $m$. In this minicourse we discuss these problems from a geometric point of view.Comment: This paper is a written-up version of the major part of a minicourse given at the sixth Bilateral Workshop on Differential Geometry and its Applications, held in Ostrava in May 201

Energy-momentum conservation in pre-metric electrodynamics with magnetic charges

A necessary and sufficient condition for energy-momentum conservation is proved within a topological, pre-metric approach to classical electrodynamics including magnetic as well as electric charges. The extended Lorentz force, consisting of mutual actions by F=(E, B) on the electric current and G=(H, D) on the magnetic current, can be derived from an energy-momentum "potential" if and only if the constitutive relation G=G(F) satisfies a certain vanishing condition. The electric-magnetic reciprocity introduced by Hehl and Obukhov is seen to define a complex structure on the tensor product of 2-form pairs (F,G) which is independent of but consistent with the Hodge star operator defined by any Lorentzian metric. Contrary to a recent claim in the literature, it does not define a complex structure on the space of 2-forms itself.Comment: 8 pages, 1 fugur

Host circadian rhythms are disrupted during malaria infection in parasite genotype-specific manners

Infection can dramatically alter behavioural and physiological traits as hosts become sick and subsequently return to health. Such “sickness behaviours” include disrupted circadian rhythms in both locomotor activity and body temperature. Host sickness behaviours vary in pathogen species-specific manners but the influence of pathogen intraspecific variation is rarely studied. We examine how infection with the murine malaria parasite, Plasmodium chabaudi, shapes sickness in terms of parasite genotype-specific effects on host circadian rhythms. We reveal that circadian rhythms in host locomotor activity patterns and body temperature become differentially disrupted and in parasite genotype-specific manners. Locomotor activity and body temperature in combination provide more sensitive measures of health than commonly used virulence metrics for malaria (e.g. anaemia). Moreover, patterns of host disruption cannot be explained simply by variation in replication rate across parasite genotypes or the severity of anaemia each parasite genotype causes. It is well known that disruption to circadian rhythms is associated with non-infectious diseases, including cancer, type 2 diabetes, and obesity. Our results reveal that disruption of host circadian rhythms is a genetically variable virulence trait of pathogens with implications for host health and disease tolerance

Adaptive periodicity in the infectivity of malaria gametocytes to mosquitoes

Daily rhythms in behaviour, physiology, and molecular processes are expected to enable organisms to appropriately schedule activities according to consequences of the daily rotation of the Earth. For parasites, this includes capitalizing on periodicity in transmission opportunities and for hosts/vectors, this may select for rhythms in immune defence. We examine rhythms in the density and infectivity of transmission forms (gametocytes) of rodent malaria parasites in the host’s blood, parasite development inside mosquito vectors, and potential for onwards transmission. Furthermore, we simultaneously test whether mosquitoes exhibit rhythms in susceptibility. We reveal that at night, gametocytes are twice as infective, despite being less numerous in the blood. Enhanced infectiousness at night interacts with mosquito rhythms to increase sporozoite burdens four-fold when mosquitoes feed during their rest phase. Thus, changes in mosquito biting time (due to bed nets) may render gametocytes less infective, but this is compensated for by the greater mosquito susceptibility

A Characterisation of the Weylian Structure of Space-Time by Means of Low Velocity Tests

The compatibility axiom in Ehlers, Pirani and Schild's (EPS) constructive axiomatics of the space-time geometry that uses light rays and freely falling particles with high velocity, is replaced by several constructions with low velocity particles only. For that purpose we describe in a space-time with a conformal structure and an arbitrary path structure the radial acceleration, a Coriolis acceleration and the zig-zag construction. Each of these quantities give effects whose requirement to vanish can be taken as alternative version of the compatibility axiom of EPS. The procedural advantage lies in the fact, that one can make null-experiments and that one only needs low velocity particles to test the compatibility axiom. We show in addition that Perlick's standard clock can exist in a Weyl space only.Comment: to appear in Gen.Rel.Gra

On the Hamilton-Jacobi Theory for Singular Lagrangian Systems

We develop a Hamilton-Jacobi theory for singular lagrangian systems using the Gotay-Nester-Hinds constraint algorithm. The procedure works even if the system has secondary constraints.Comment: 36 page

Friedmann Robertson-Walker model in generalised metric space-time with weak anisotropy

A generalized model of space-time is given, taking into consideration the anisotropic structure of fields which are depended on the position and the direction (velocity).In this framework a generalized FRW-metric the Raychaudhouri and Friedmann equations are studied.A long range vector field of cosmological origin is considered in relation to the physical geometry of space-time in which Cartan connection has a fundamental role.The generalised Friedmann equations are produced including anisotropic terms.The variation of anisotropy $z_t$ is expressed in terms of the Cartan torsion tensor of the Finslerian space-time.A possible estimation of the anisotropic parameter $z_t$ can be achieved with the aid of the de-Sitter model of the empty flat universe with weak anisotropy. Finally a physical generalisation for the model of inflation is also studied.Comment: 21 pages- to appear in GR