Field Theoretical Analysis of On-line Learning of Probability Distributions

On-line learning of probability distributions is analyzed from the field theoretical point of view. We can obtain an optimal on-line learning algorithm, since renormalization group enables us to control the number of degrees of freedom of a system according to the number of examples. We do not learn parameters of a model, but probability distributions themselves. Therefore, the algorithm requires no a priori knowledge of a model.Comment: 4 pages, 1 figure, RevTe

Inpatient case fatality rates improvements in children under 5: Diarrhoeal disease, pneumonia and severe acute malnutrition

Data on the number of admissions and deaths in children aged under 5 years from diarrhoea, pneumonia and severe acute malnutrition are routinely collected through the District Health Information System. These data, and the associated case fatality rates, are available for all public sector hospitals in South Africa (SA), and can be compared over time, as well as across different settings. This article presents these data for the period 2011/12 - 2016/17. It reflects on the remarkable improvements in these case fatality rates, and the likely reasons for their declines across all provinces. The article concludes by identifying the actions that need to be taken to ensure that SA achieves the Sustainable Development Goal aim of ending preventable child deaths by 2030

Three-day changes in resting metabolism after a professional young rugby league match

Professional collision-sport athletes report uniquely large energy expenditures across the season (1-4), as determined by gold standard assessment of resting metabolic rate (RMR (5)) and total energy expenditure (TEE (6)). Such expenditures are possibly a consequence of strenuous match demands, which repeatedly expose players to substantial exercise-and collision-induced muscle damage (7). Recovery from such large perturbations of homeostasis (8) are likely to be energetically expensive (9), in part determining the distinct in-season energetic demands of professional collision-sport athletes. Aim. Accurately determining the effect of match play on resting metabolism is essential to optimise acute manipulation of energy balance, player recovery and long-term athlete development. Therefore, for the first time this case report investigated the metabolic cost of a professional young rugby league match

The Effect of Larval Diet and Sex on Nectar Nicotine Feeding Preferences in Manduca Sexta (Lepidoptera: Sphingidae)

The article offers information on the study conducted regarding the implication of larval diet and nectar nicotine feeding to the sexual behavior of Manduca Sexta. Researchers found that many of these lepidoptera interact with the same plant species, both herbivorous larvae and nectar-feeding adults. Moreover, they found that the said behavior paves the way to influence both pollination and herbivory in floral and foliar tissue

The investigation of absolute proper motions of the XPM Catalogue

The XPM-1.0 is the regular version of the XPM catalogue. In comparison with XPM the astrometric catalogue of about 280 millions stars covering entire sky from -90 to +90 degrees in declination and in the magnitude range 10^m<B<22^m is something improved. The general procedure steps were followed as for XPM, but some of them are now performed on a more sophisticated level. The XPM-1.0 catalogue contains star positions, proper motions, 2MASS and USNO photometry of about 280 millions of the sources. We present some investigations of the absolute proper motions of XPM-1.0 catalogue and also the important information for the users of the catalogue. Unlike previous version, the XPM-1.0 contains the proper motions over the whole sky without gaps. In the fields, which cover the zone of avoidance or which contain less than of 25 galaxies a quasi absolute calibration was performed. The proper motion errors are varying from 3 to 10 mas/yr, depending on a specific field. The zero-point of the absolute proper motion frame (the absolute calibration) was specified with more than 1 million galaxies from 2MASS and USNO-A2.0. The mean formal error of absolute calibration is less than 1 mas/yr.Comment: 11 pages, 9 figures, accepte

Nonreciprocal Directional Dichroism and Toroidalmagnons in Helical Magnets

We investigate a dynamical magnetoelectric effect due to a magnetic resonance in helical spin structures through the coupling between magnetization and electric polarization via a spin current mechanism. We show that the magnon has both the dynamical magnetic moment $\Delta M^\omega$ and the electric moment $\Delta P^\omega$ ($\perp \Delta M^\omega$), i.e., a dynamical toroidal moment, under external magnetic fields, and thus it is named the {\em toroidalmagnon}. The toroidalmagnon exists in most conical spin structures owing to the generality of the spin current mechanism. In the absorption of electromagnetic waves, the toroidalmagnon excitation process generally induces a nonreciprocal directional dichroism as a consequence of an interference of the magnetic and electric responses.Comment: 5 pages, 2 figure

Reducing neonatal deaths in South Africa: Progress and challenges

Although current levels of the neonatal mortality rate (NMR) are within reach of the Sustainable Development Goal (SDG) target of 12 per 1 000 live births, the absolute number of deaths is unacceptably high for a lower-middle-income country such as South Africa (SA). Neonatal mortality over the last decade has declined very slowly, and is not commensurate with the level of government investment in healthcare. The recent neonatal mortality rate of 21 per 1 000 live births reported by the SA Demographic Health Survey is of major concern. This paper reviews recent efforts to reduce the neonatal mortality rate, including support for the implementation of neonatal policies and plans, and strengthening programmes to deliver low-cost, high-impact interventions. We review recent estimates of the NMR and causes of neonatal deaths, and discuss how the mortality from preventable causes of death could be reduced. If SA is to meet the SDG target, special attention should be given to the availability of high-impact interventions, providing an adequate number of appropriately trained healthcare providers and a more active role played by ward-based community health workers and district clinical specialist teams

Chiral discrimination in optical trapping and manipulation

When circularly polarized light interacts with chiral molecules or nanoscale particles powerful symmetry principles determine the possibility of achieving chiral discrimination, and the detailed form of electrodynamic mechanisms dictate the types of interaction that can be involved. The optical trapping of molecules and nanoscale particles can be described in terms of a forward-Rayleigh scattering mechanism, with trapping forces being dependent on the positioning within the commonly non-uniform intensity beam profile. In such a scheme, nanoparticles are commonly attracted to local potential energy minima, ordinarily towards the centre of the beam. For achiral particles the pertinent material response property usually entails an electronic polarizability involving transition electric dipole moments. However, in the case of chiral molecules, additional effects arise through the engagement of magnetic counterpart transition dipoles. It emerges that, when circularly polarized light is used for the trapping, a discriminatory response can be identified between left- and right-handed polarizations. Developing a quantum framework to accurately describe this phenomenon, with a tensor formulation to correctly represent the relevant molecular properties, the theory leads to exact analytical expressions for the associated energy landscape contributions. Specific results are identified for liquids and solutions, both for isotropic media and also where partial alignment arises due to a static electric field. The paper concludes with a pragmatic analysis of the scope for achieving enantiomer separation by such methods

Algebraic varieties with automorphism groups of maximal rank

We confirm, to some extent, the belief that a projective variety X has the largest number (relative to the dimension of X) of independent commuting automorphisms of positive entropy only when X is birational to a complex torus or a quotient of a torus. We also include an addendum to an early paper though it is not used in the present paper.Comment: Mathematische Annalen (to appear