944 resultados para fibered knots and links open book decomposition surgerycontact structures contact forms


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Nutrition is central to health and children's diets can be an important influence now and in the future. Stop, Look and Cook is a new recipe book for use by catering staff in all grant-aided nursery, primary and post-primary schools in Northern Ireland.�Recipes have been collected from school caterers across the region. These recipes have been checked to ensure that they are compliant with nutritional standards for school lunches and have been tested in schools for taste and suitability. In addition all the recipes have been analysed by the PHA using a nutritional software package, with a particular focus on fat, salt and sugar.�This recipe book provides approximately 280 recipes, giving schools more choice for menus. It also contains useful advice for dealing with food allergies and supplying alternative meals for pupils from other cultures.For more information on Stop, Look and Cook please contact the school meals catering manager at your local Education and Library Board.�

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In recent years there has been growing interest in the question of how the particular topology of polymeric chains affects their overall dimensions and physical behavior. The majority of relevant studies are based on numerical simulation methods or analytical treatment; however, both these approaches depend on various assumptions and simplifications. Experimental verification is clearly needed but was hampered by practical difficulties in obtaining preparative amounts of knotted or catenated polymers with predefined topology and precisely set chain length. We introduce here an efficient method of production of various single-stranded DNA knots and catenanes that have the same global chain length. We also characterize electrophoretic migration of the produced single-stranded DNA knots and catenanes with increasing complexity.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The aim of this study was to calibrate the CENTURY, APSIM and NDICEA simulation models for estimating decomposition and N mineralization rates of plant organic materials (Arachis pintoi, Calopogonium mucunoides, Stizolobium aterrimum, Stylosanthes guyanensis) for 360 days in the Atlantic rainforest bioma of Brazil. The models´ default settings overestimated the decomposition and N-mineralization of plant residues, underlining the fact that the models must be calibrated for use under tropical conditions. For example, the APSIM model simulated the decomposition of the Stizolobium aterrimum and Calopogonium mucunoides residues with an error rate of 37.62 and 48.23 %, respectively, by comparison with the observed data, and was the least accurate model in the absence of calibration. At the default settings, the NDICEA model produced an error rate of 10.46 and 14.46 % and the CENTURY model, 21.42 and 31.84 %, respectively, for Stizolobium aterrimum and Calopogonium mucunoides residue decomposition. After calibration, the models showed a high level of accuracy in estimating decomposition and N- mineralization, with an error rate of less than 20 %. The calibrated NDICEA model showed the highest level of accuracy, followed by the APSIM and CENTURY. All models performed poorly in the first few months of decomposition and N-mineralization, indicating the need of an additional parameter for initial microorganism growth on the residues that would take the effect of leaching due to rainfall into account.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Comment on: Witz G, et al. Proc Natl Acad Sci USA 2011; 108:3608-11.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We address the general question of the extent to which the hydrodynamic behaviour of microscopic freely fluctuating objects can be reproduced by macrosopic rigid objects. In particular, we compare the sedimentation speeds of knotted DNA molecules undergoing gel electrophoresis to the sedimentation speeds of rigid stereolithographic models of ideal knots in both water and silicon oil. We find that the sedimentation speeds grow roughly linearly with the average crossing number of the ideal knot configurations, and that the correlation is stronger within classes of knots. This is consistent with previous observations with DNA knots in gel electrophoresis.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background: Some countries have recently extended smoke-free policies to particular outdoor settings; however, there is controversy regarding whether this is scientifically and ethically justifiable. Objectives: The objective of the present study was to review research on secondhand smoke (SHS) exposure in outdoor settings. Data sources: We conducted different searches in PubMed for the period prior to September 2012. We checked the references of the identified papers, and conducted a similar search in Google Scholar. Study selection: Our search terms included combinations of"secondhand smoke,""environmental tobacco smoke,""passive smoking" OR"tobacco smoke pollution" AND"outdoors" AND"PM" (particulate matter),"PM2.5" (PM with diameter ≤ 2.5 µm),"respirable suspended particles,""particulate matter,""nicotine,""CO" (carbon monoxide),"cotinine,""marker,""biomarker" OR"airborne marker." In total, 18 articles and reports met the inclusion criteria. Results: Almost all studies used PM2.5 concentration as an SHS marker. Mean PM2.5 concentrations reported for outdoor smoking areas when smokers were present ranged from 8.32 to 124 µg/m3 at hospitality venues, and 4.60 to 17.80 µg/m3 at other locations. Mean PM2.5 concentrations in smoke-free indoor settings near outdoor smoking areas ranged from 4 to 120.51 µg/m3. SHS levels increased when smokers were present, and outdoor and indoor SHS levels were related. Most studies reported a positive association between SHS measures and smoker density, enclosure of outdoor locations, wind conditions, and proximity to smokers. Conclusions: The available evidence indicates high SHS levels at some outdoor smoking areas and at adjacent smoke-free indoor areas. Further research and standardization of methodology is needed to determine whether smoke-free legislation should be extended to outdoor settings.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Tutkimuksessa tarkastellaan OBA:n soveltamisen hyötyjä ja haasteita erityyppisissä yritysten välisissä suhteissa.Tutkimuksen tavoitteena on vastata kysymykseen, mitä erilaisia tavoitteita liiketoimintasuhteiden taustalla esiintyy, tyypitellä liiketoimintasuhteet tavoitteiden ja yritysten välisten toimintojen näkökulmasta ja arvioida miten OBA voi auttaa erityyppisien suhteiden johtamista tukevan informaation tuottamisessa ja hyödyntämisessä. Markkinaperustaisissa suhteissa vaihdannan avulla tavoitellaan tehokkuutta jonka perustana on markkinoilla vallitsevan kilpailun tehokkuus. Neuvotteluvoimaan perustuvissa suhteissa tavoitteena on hankkia resursseja sisäisiä tuotantokustannuksia edullisemmin markkinavoimaa hyväksikäyttämällä. Yhteistyösuhteissa toimittajan kyky tuottaa resurssi sisäisiin tuotantokustannuksiin nähden kilpailukykyisellä hinnalla perustuu vallitseviin mittakaavaetuihin tai erikoistumisen tuomaan osaamiseen ja niissä pyritään saavuttamaan kilpailuetua yritysten osaamista ja resursseja yhdistämällä. Yhteistyösuhteet voidaan jakaa operatiivisiin, taktisiin ja strategisiin yritysten välisten toimintojen integroituneisuuden ja strategisen merkityksen perusteella. Tutkimus antaa viitteitä siitä että OBA:n soveltamisen suurin potentiaali liittyy taktisiin ja strategisiin yhteistyösuhteisiin, koska niissä yritysten välisten toimintojen määrä on merkittävä ja yhteiset tavoitteet lisäävät yritysten välistä luottamusta.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Kirjallisuusarvostelu

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The book is bound in a leather case with a clasp in the front. Inside is printed "S.D. Woodruff, St. Catharines, C.W." in the front of the book and there is a label which says "Band, 74 De Vere Gardens, Toronto 20, Ontario". A full text version of this book is available at the following link: https://archive.org/details/haswellsengineer00hasw

Relevância:

100.00% 100.00%

Publicador:

Resumo:

UANL

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In this thesis we are studying possible invariants in hydrodynamics and hydromagnetics. The concept of flux preservation and line preservation of vector fields, especially vorticity vector fields, have been studied from the very beginning of the study of fluid mechanics by Helmholtz and others. In ideal magnetohydrodynamic flows the magnetic fields satisfy the same conservation laws as that of vorticity field in ideal hydrodynamic flows. Apart from these there are many other fields also in ideal hydrodynamic and magnetohydrodynamic flows which preserves flux across a surface or whose vector lines are preserved. A general study using this analogy had not been made for a long time. Moreover there are other physical quantities which are also invariant under the flow, such as Ertel invariant. Using the calculus of differential forms Tur and Yanovsky classified the possible invariants in hydrodynamics. This mathematical abstraction of physical quantities to topological objects is needed for an elegant and complete analysis of invariants.Many authors used a four dimensional space-time manifold for analysing fluid flows. We have also used such a space-time manifold in obtaining invariants in the usual three dimensional flows.In chapter one we have discussed the invariants related to vorticity field using vorticity field two form w2 in E4. Corresponding to the invariance of four form w2 ^ w2 we have got the invariance of the quantity E. w. We have shown that in an isentropic flow this quantity is an invariant over an arbitrary volume.In chapter three we have extended this method to any divergence-free frozen-in field. In a four dimensional space-time manifold we have defined a closed differential two form and its potential one from corresponding to such a frozen-in field. Using this potential one form w1 , it is possible to define the forms dw1 , w1 ^ dw1 and dw1 ^ dw1 . Corresponding to the invariance of the four form we have got an additional invariant in the usual hydrodynamic flows, which can not be obtained by considering three dimensional space.In chapter four we have classified the possible integral invariants associated with the physical quantities which can be expressed using one form or two form in a three dimensional flow. After deriving some general results which hold for an arbitrary dimensional manifold we have illustrated them in the context of flows in three dimensional Euclidean space JR3. If the Lie derivative of a differential p-form w is not vanishing,then the surface integral of w over all p-surfaces need not be constant of flow. Even then there exist some special p-surfaces over which the integral is a constant of motion, if the Lie derivative of w satisfies certain conditions. Such surfaces can be utilised for investigating the qualitative properties of a flow in the absence of invariance over all p-surfaces. We have also discussed the conditions for line preservation and surface preservation of vector fields. We see that the surface preservation need not imply the line preservation. We have given some examples which illustrate the above results. The study given in this thesis is a continuation of that started by Vedan et.el. As mentioned earlier, they have used a four dimensional space-time manifold to obtain invariants of flow from variational formulation and application of Noether's theorem. This was from the point of view of hydrodynamic stability studies using Arnold's method. The use of a four dimensional manifold has great significance in the study of knots and links. In the context of hydrodynamics, helicity is a measure of knottedness of vortex lines. We are interested in the use of differential forms in E4 in the study of vortex knots and links. The knowledge of surface invariants given in chapter 4 may also be utilised for the analysis of vortex and magnetic reconnections.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The paper will consist of three parts. In part I we shall present some background considerations which are necessary as a basis for what follows. We shall try to clarify some basic concepts and notions, and we shall collect the most important arguments (and related goals) in favour of problem solving, modelling and applications to other subjects in mathematics instruction. In the main part II we shall review the present state, recent trends, and prospective lines of development, both in empirical or theoretical research and in the practice of mathematics instruction and mathematics education, concerning problem solving, modelling, applications and relations to other subjects. In particular, we shall identify and discuss four major trends: a widened spectrum of arguments, an increased globality, an increased unification, and an extended use of computers. In the final part III we shall comment upon some important issues and problems related to our topic.