A note on the examination of isospin effects in multi-dimensional Langevin fission dynamics

AbstractIn [W. Ye, F. Wu, H.W. Yang, Phys. Lett. B 647 (2007) 118] prescission protons and α particles of high-isospin 206Pb were shown to be almost independent of the dissipation strength ks. Subsequently, in [P.N. Nadtochy, et al., Phys. Lett. B 685 (2010) 258] prescission light charged particles (LCPs) were shown to have approximately the same sensitivity as neutrons to ks for 206Pb and 204Hg nuclei. In this Letter we point out that the reason for the apparent contradictory conclusions is that the authors in the latter did not compute the changes in the absolute yields of prescission LCPs multiplicities with increasing ks and compare them with typical experimental uncertainties. It is shown that the expected changes are very small in the case of neutron-rich 206Pb and 204Hg systems, which are within experimental error bars. This indicates that, from the viewpoint of experiment, LCPs emission of 206Pb and 204Hg is insensitive to dissipation

Ranges of critical temperature and water potential values for the germination of species worldwide: Contribution to a seed trait database

Germination is the first essential stage in crop and food production, as well as for the establishment of trees and regeneration of wild species. Temperature and water potential are the primary environmental factors that control germination in all species, and affect both the rate and final percentage germination. A comprehensive description of intra- and inter-variations between groups of species (perennials and annuals, trees, grasses, crops and wild species) helps understand where these species are currently able to grow on earth and will be in the future. By collecting germination trait data on 243 species from the literature and unpublished data, we provide a wide spectrum of species’ seed germination traits, in the form of a set of parameter values describing germination responses to variations in temperature and water potential. Major differences in germination traits were seen to depend on the climatic conditions where the species grow or originated, with species able to germinate on ice and others unable to germinate below 18 °C. By contrast, within the different plant groups, similar ranges of threshold values were found, linked to the species geo-climatic origin. Crops however germinate faster, their range of threshold temperatures and water potential values is wider, and some crops have higher optimum and maximum temperatures as well as lower water potential threshold values. This is likely the result of human selection for rapid germination and for species able to grow in the wide range of environmental conditions where agriculture was developed. Our analyses revealed correlation between traits: negative correlations appeared between germination speed and temperature thresholds, and between temperature and water potential thresholds. The collected data also form a valuable database, enabling plant establishment to be better taken into account in modeling and simulation studies of vegetation boundaries (wild or cultivated) under changing land-use and climate

Initiation of an early mobilisation programme in intensive care units—A preliminary report

The Tropical Agriculturalist series Livestock product/on systems examines how individual species of domestic livestock can be integrated into the whole concept of sustainable agriculture in the tropics. The main part of the book is devoted to a series of case studies covering most, if not all, of the systems of livestock husbandry used in the tropics. The reasons why these systems have been developed are outlined, their limitations highlighted and the ways in which they could be improved are discussed. This part of the book is a useful short reference work presenting the main features of the extremely varied livestock production systems found across the tropics. Readers of the book will obtain a good insight into how livestock and crop husbandry can be linked in the wetter regions of the tropics to improve the use of resources. In the dry regions of the tropics, where crop husbandry is not an option, animal husbandry is the best way of utilizing these regions for the benefit of people. The book shows how livestock are essential for the development of ecologically sound systems of food production. All types of livestock are covered including buffalo, camels and poultry. Livestock production systems by Trevor Wilson 1995 141pp ISBN 0 333 60012 6 Animal health volume/explains the causes of animal diseases, how they are spread and the means available for their control. It covers not only diseases caused by micro-organisms, arthropods and helminths, but also deals with metabolic diseases and those caused by toxins. The signs of health and the symptoms to look for when an animal is suspected of being diseased are clearly presented using simple diagnostic keys. Tables are included to assist in diagnosis of diseases in the major farm animals found in the tropics. The book concludes by dealing with general veterinary procedures, including the administration of medicines. The book is a valuable guide for anyone involved with maintaining and establishing the health of animals in tropical and subtropical countries. It should be read in conjunction with volume 2 (which appeared earlier) and those volumes in the series which deal with individual animal species. Animal health volume l: general principles by Archie Hunter 1996 167pp ISBN 0 333 61202 7 Avocado is a succinct guide to the cultivation and marketing of a fruit of growing commercial importance throughout the world. It covers the plant's origins and distribution, botany, and selection and breeding. as well as providing more detailed guidance on the field operations needed to grow this sensitive crop successfully. Land preparation, the choice of cultivars and rootstocks, grafting techniques, irrigation requirements, and major pests and diseases are some of the topics covered. Lastly, the book turns to harvesting and processing considerations, with special emphasis on the requirements for export. A wealth of photographs, line drawings, tables and charts support the text, which is based on the authors' 20 years of experience as well as extensive reference to the global literature. Avocado by J P Gaillard and d Godefroy 1995 120pp ISBN 0 333 57468 0 The above titles are part of the Macmillan The Tropical Agriculturalist series which is published in association with, and are available from, CTA.The Tropical Agriculturalist seriesLivestock product/on systems examines how individual species of domestic livestock can be integrated into the whole concept of sustainable agriculture in the tropics. The main part of the book is devoted to a..

Oscillating flames in open tubes

When a flame passes along a tube that is open at both ends a self induced fluctuating pressure/flow field is created which the flame has to traverse. Here fuel rich (1.1 < ϕ < 1.4) propane-air flames have been filmed travelling along a 20 mm internal diameter quartz tube. Fluctuations in the flame’s progression were observed to increase as the flame propagated, achieving a maximum oscillation amplitude of ±10 mm at 220 Hz that decayed as the flame progressed further towards the end of the tube. The impact of the periodic pressure gradients on the flame shape could be discerned with tongues of unburned reactants pushed into the products as well as the corresponding rapid acceleration of the flame into the unburned mixture. The impact of the fluctuations on flame chemistry was monitored by capturing the CH∗ and C2 chemiluminescence using a high speed colour camera. The CH∗/C2∗ ratio was observed to decrease as the flame was pulled back towards the burned mixture; and increased when the flame was pushed forwards. This was consistent throughout the flame progress even when small oscillations in the flame position were measured. This could be a significant feature of flames in this environment

A Generalized Circle Theorem on Zeros of Partition Function at Asymmetric First Order Transitions

We present a generalized circle theorem which includes the Lee-Yang theorem for symmetric transitions as a special case. It is found that zeros of the partition function can be written in terms of discontinuities in the derivatives of the free energy. For asymmetric transitions, the locus of the zeros is tangent to the unit circle at the positive real axis in the thermodynamic limit. For finite-size systems, they lie off the unit circle if the partition functions of the two phases are added up with unequal prefactors. This conclusion is substantiated by explicit calculation of zeros of the partition function for the Blume-Capel model near and at the triple line at low temperatures.Comment: 10 pages, RevTeX. To be published in PRL. 3 Figures will be sent upon reques

Crystal structure of (La, Ca) MnO 3 ultrathin films deposited on SrTiO 3 substrates

Quantum Matter and Optic

Quantifying the levitation picture of extended states in lattice models

The behavior of extended states is quantitatively analyzed for two dimensional lattice models. A levitation picture is established for both white-noise and correlated disorder potentials. In a continuum limit window of the lattice models we find simple quantitative expressions for the extended states levitation, suggesting an underlying universal behavior. On the other hand, these results point out that the Quantum Hall phase diagrams may be disorder dependent.Comment: 5 pages, submitted to PR

New Results for the Correlation Functions of the Ising Model and the Transverse Ising Chain

In this paper we show how an infinite system of coupled Toda-type nonlinear differential equations derived by one of us can be used efficiently to calculate the time-dependent pair-correlations in the Ising chain in a transverse field. The results are seen to match extremely well long large-time asymptotic expansions newly derived here. For our initial conditions we use new long asymptotic expansions for the equal-time pair correlation functions of the transverse Ising chain, extending an old result of T.T. Wu for the 2d Ising model. Using this one can also study the equal-time wavevector-dependent correlation function of the quantum chain, a.k.a. the q-dependent diagonal susceptibility in the 2d Ising model, in great detail with very little computational effort.Comment: LaTeX 2e, 31 pages, 8 figures (16 eps files). vs2: Two references added and minor changes of style. vs3: Corrections made and reference adde

Wigner Crystals Phases in Bilayer Quantum Hall Systems

(This is a substantially shortened version of the original abstract:) The Wigner crystal phase diagram of the bilayer systems have been studied using variational methods. Five crystal phases are obtained. As the layer spacing increases, the system will undergo a sequence of phase transitions. A common feature of most bilayer Wigner crystals is that they have mixed (pseudo-spin) ferromagnetic and antiferromagnetic order.Comment: 19 figures. Figures will be provided upon request. Submitted in PRB in Nov 94

Vertical Confinement and Evolution of Reentrant Insulating Transition in the Fractional Quantum Hall Regime

We have observed an anomalous shift of the high field reentrant insulating phases in a two-dimensional electron system (2DES) tightly confined within a narrow GaAs/AlGaAs quantum well. Instead of the well-known transitions into the high field insulating states centered around $\nu = 1/5$, the 2DES confined within an 80\AA-wide quantum well exhibits the transition at $\nu = 1/3$. Comparably large quantum lifetime of the 2DES in narrow well discounts the effect of disorder and points to confinement as the primary driving force behind the evolution of the reentrant transition.Comment: 5 pages, 4 figure