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In our recent reassessment we explored the risk of MS by age at immigration in 258 migrants from United Kingdom and Ireland (UKI) to four states of Australia (New South Wales, Queensland, South Australia, and Western Australia) in the period 1947-1981 (Group II). In the present report we have compared their characteristics with 44 cases who migrated before 1947 (Group I), divided into two subsets: Group Ia (15 cases) was rather similar to Group II in age at immigration (means of 20 and 23 years), age at onset (39 and 33 years), and duration from immigration to onset (19 and 10 years). Group Ib (29 cases) was significantly different from Group II, with mean ages of 4 years at immigration and 40 years at onset, for a mean interval of some 35 years between immigration and onset. All onsets in Group Ib occurred after 1947. We concluded that the Group Ib cases had most probably acquired their MS in Australia. Immigrants from high MS risk countries, including UKI, were modest in number before 1947, but some 770,000 entered from 1947-1981. They may have been the source of MS for the Group Ib migrants. [ABSTRACT FROM AUTHOR]

We have investigated the electronic structure and the Fermi surface of SnO using density functional theory calculations within recently proposed exchange-correlation potential (PBE + mBJ) at ambient conditions and high pressures up to 19.3 GPa where superconductivity was observed. It was found that the Sn valence states (5 s, 5 p, and 5 d are strongly hybridized with the O 2 p states, and that our density functional theory calculations are in good agreement with O K-edge X-ray spectroscopy measurements for both occupied and empty states. It was demonstrated that the metallic states appearing under pressure in the semiconducting gap stem due to the transformation of the weakly hybridized O 2 p-Sn 5 sp subband corresponding to the lowest valence state of Sn in SnO. We discuss the nature of the electronic states involved in chemical bonding and formation of the hole and electron pockets with nesting as a possible way to superconductivity. [ABSTRACT FROM AUTHOR]

We consider mass-conserving self-similar solutions for Smoluchowski's coagulation equation with kernel K( ξ, η)=( ξη) with λ∈(0,1/2). It is known that such self-similar solutions g( x) satisfy that x g( x) is bounded above and below as x→0. In this paper we describe in detail via formal asymptotics the qualitative behavior of a suitably rescaled function h( x)= h x g( x) in the limit λ→0. It turns out that $h \sim 1+ C x^{\lambda/2} \cos(\sqrt{\lambda} \log x)$ as x→0. As x becomes larger h develops peaks of height 1/ λ that are separated by large regions where h is small. Finally, h converges to zero exponentially fast as x→∞. Our analysis is based on different approximations of a nonlocal operator, that reduces the original equation in certain regimes to a system of ODE. [ABSTRACT FROM AUTHOR]

previous study of the prevalence of multiple sclerosis (MS) in 1981 among immigrants from the United Kingdom and Ireland to Australia found that the prevalence for those with age at immigration (AAI) under 15 years of age did not differ from the older immigrants. We have reanalysed the original materials as well as census data for 1901-1981 for UKI and other high MS risk country immigrants. There was a highly significant trend in the prevalence rates of all Australians from New South Wales (NSW) to South Australia (SA) to Western Australia (WA) to Queensland (QLD). Rates by state among the Australian-born were almost identical to these, but there was no prevalence gradient for the UKI-born. The denominator population at risk of MS by AAI was calculated from special census tables of length of residence in Australia by age 0-79 in 1981 for UKI immigrants 1947-1981. The numerator was limited to the subset of 258 MS (Group II) also immigrating in 1947 and later, and age 0-79 in 1981. The absolute risk of MS for these migrants to the four states entering at age 0-14 was 22/100,000, significantly less than for all older age groups; age 15-39 immigrants had a risk of 54/100,000. Similar risk ratios for 0-14 versus 15-39 by state were 31 versus 61 (NSW), 29 versus 44 (QLD), 11 versus 50 (SA), 15 versus 51 (WA). [ABSTRACT FROM AUTHOR]

We consider an equation for the evolution of growing and dividing cells, and show, using a result of Kato and McLeod, that the probability density function for the stationary size distribution is necessarily unimodal. [ABSTRACT FROM AUTHOR]

Objectives: Pharmacodynamic effects of nateglinide, a novel antidiabetic agent, were investigated in patients with type-2 diabetes mellitus. Methods: Ten patients participated in this single-center, double-blind, crossover study. Plasma glucose and insulin levels were measured over 24 h following five 7-day treatment periods with nateglinide (30, 60, or 120 mg) or placebo given three times daily before breakfast, lunch, and dinner. A fifth treatment consisted of 120 mg nateglinide four times daily, with the fourth dose given before an evening snack. Results: Taken 10 min before meals, doses of 30–120 mg nateglinide caused dose-dependent increases in plasma insulin levels that were significantly greater than with placebo. Higher doses were more effective and had a longer duration of action than lower doses. Nateglinide was also significantly better than placebo in lowering plasma glucose levels; the 60-mg and 120-mg doses were similarly effective and superior to the 30-mg nateglinide treatment. Following the fourth 120-mg dose, the glucose-lowering effects of treatment were maintained through the night. No serious adverse events occurred during the study. There were no events of hypoglycemia and no clinically meaningful changes in safety parameters. Conclusions: Nateglinide produced rapid, short-lived, dose-related increases in plasma insulin that significantly lowered mealtime glucose excursions compared with placebo with no incidence of hypoglycemia. The decrease in mealtime glucose levels produced a significant improvement in overall 24-h glycemia. [ABSTRACT FROM AUTHOR]

We consider the second Painlevé transcendent It is known that if y(x) ∼ k Ai (x) as x → + ∞, where −1< k<1 and Ai ( x) denotes Airy's function, then where the constants d, c depend on k. This paper shows that , which confirms a conjecture by Ablowitz & Segur. [ABSTRACT FROM AUTHOR]

The paper is concerned with the asymptotic behavior as t → ∞ of solutions u(x,t) of the equation $$u_t - u_{xx} - f\left( u \right) = 0, x \in \left( { - \infty ,\infty } \right),$$ in the case f(0)= f(1)=0, with f(u) non-positive for u(>0) sufficiently close to zero and f(u) non-negative for u(<1) sufficiently close to 1. This guarantees the uniqueness (but not the existence) of a travelling front solution u;U(x−ct), U(−∞);0, U(∞);, and it is shown in essence that solutions with monotonic initial data converge to a translate of this travelling front, if it exists, and to a 'stacked' combination of travelling fronts if it does not. The approach is to use the monotonicity to take u and t as independent variables and p = u as the dependent variable, and to apply ideas of sub- and super-solutions to the diffusion equation for p. [ABSTRACT FROM AUTHOR]

The differential equation considered is $$y'' - xy = y|y|^\alpha $$ . For general positive α this equation arises in plasma physics, in work of De Boer & Ludford. For α=2, it yields similarity solutions to the well-known Korteweg-de Vries equation. Solutions are sought which satisfy the boundary conditions (1) y(∞)=0 (2) It is shown that there is a unique such solution, and that it is, in a certain sense, the boundary between solutions which exist on the whole real line and solutions which, while tending to zero at plus infinity, blow up at a finite x. More precisely, any solution satisfying (1) is asymptotic at plus infinity to some multiple kA i(x) of Airy's function. We show that there is a unique k(α) such that when k=k(α) the condition (2) is also satisfied. If 0k then the solution blows up at a finite x. For the special case α=2 the differential equation is classical, having been studied by Painlevé around the turn of the century. In this case, using an integral equation derived by inverse scattering techniques by Ablowitz & Segur, we are able to show that k=1, confirming previous numerical estimates. [ABSTRACT FROM AUTHOR]

The paper is concerned with the asymptotic behavior as t → ∞ of solutions u(x, t) of the equation u-u-∞;(u)=O, x∈(-∞, ∞) , in the case ∞(0)=∞(1)=0, ∞′(0)<0, ∞′(1)<0. Commonly, a travelling front solution u=U(x-ct), U(-∞)=0, U(∞)=1, exists. The following types of global stability results for fronts and various combinations of them will be given. [ABSTRACT FROM AUTHOR]

The paper discusses conditions under which the formally self-adjoint elliptic differential operator in R given by has a unique self-adjoint extension. The novel feature is that the major conditions on the coefficients have to be imposed only in an increasing sequence of shell-like regions surrounding the origin. On the other hand it is shown that if these shells are broken so as to allow a tube extending to infinity in which the conditions on the coefficients are too weak, then, regardless of the coefficients elsewhere, there may not be a unique self-adjoint extension. The mathematical theorems are linked to the quantum-mechanical interpretation of essential self-adjointness (in the case that τ is the Schrödinger operator), that there is a unique self-adjoint extension if the particle cannot escape to infinity in a finite time. [ABSTRACT FROM AUTHOR]

We consider operator equations of the form , (1) where A, B are linear operators between real Banach spaces and N(λ, u) is a nonlinear operator with the property that N(λ, 0)=0 for all real λ. Assuming that λ, a specific value of λ, is an isolated eigenvalue of A − λB of multiplicity m, we study the phenomenon of bifurcation for equation (1), where it is merely assumed that N(λ, u) is Lipschitz continuous in u near u=0 with a small Lipschitz constant. It is shown that when (1) has a variational structure, for each suitable normalization of u, two non-zero solutions ( λ, u) occur near (λ,0) ( m pairs occur if N is odd in u). Further results concern the existence of branches of solutions when m is odd and the asymptotic behavior of solutions in terms of the size of the Lipschitz constant. The motivation for the study and the main application of the results concerns buckling of a von Kármán plate resting on a foundation. [ABSTRACT FROM AUTHOR]

This paper studies the boundary-value problem arising from the behaviour of a fluid occupying the region -1≦x≦1 between two rotating disks, rotating about a common axis perpendicular to their planes when the disks are rotating with the same speed Ω but in the opposite sense. The equations which describe the axially symmetric similarity solutions of this problem are with the boundary conditions where ɛ=v/2Ω and v is the kinematic viscosity. The existence of an odd solution is established. This particular solution satisfies many special conditions, for example, G′ (x, ɛ)>0. Moreover, precise estimates are obtained on the size and behaviour of the solution as ɛ ↓ 0. [ABSTRACT FROM AUTHOR]

We study the equations for two-dimensional irrotational motion induced in a rectangular tank of water which is forced to oscillate horizontally in a periodic fashion ('shallow water sloshing'). The problem reduces to a second-order non-autonomous ordinary differential equation. We rigorously show the existence of many solutions obtained previously by numerical computations, and in addition we show that there are many other bounded solutions. We use simple shooting to obtain irregular solutions of the kind obtained by the methods of dynamical systems. In addition, we obtain a kind of 'kneading' theory whereby we can order the initial conditions according to the pattern of 'spikes' exhibited by the solutions. [ABSTRACT FROM AUTHOR]

We consider the Einstein/Yang-Mills equations in 3+1 space time dimensions with SU(2) gauge group and prove rigorously the existence of a globally defined smooth static solution. We show that the associated Einstein metric is asymptotically flat and the total mass is finite. Thus, for non-abelian gauge fields the Yang-Mills repulsive force can balance the gravitational attractive force and prevent the formation of singularities in spacetime. [ABSTRACT FROM AUTHOR]

In this work we propose a new method for investigating connection problems for the class of nonlinear second order differential equations known as the Painlevé equations. Such problems can be characterized by the question as to how the asymptotic behaviours of solutions are related as the independent variable is allowed to pass towards infinity along different directions in the complex plane. Connection problems have been previously tackled by a variety of methods. Frequently these are based on the ideas of isomonodromic deformation and the matching of WKB solutions. However, the implementation of these methods often tends to be heuristic in nature and so the task of rigorising the process is complicated. The method we propose here develops uniform approximations to solutions. This removes the need to match solutions, is rigorous, and can lead to the solution of connection problems with minimal computational effort. Our method relies on finding uniform approximations of differ ential equations of the generic form $$ \frac{{\text d}^2\phi}{{\text d}\eta^2} = - \xi^2F(\eta,\xi)\phi $$ as the complex valued parameter $\xi \to \infty$ . The details of the treatment rely heavily on the locations of the zeros of the function F in this limit. If they are isolated, then a uniform approximation to solutions can be derived in terms of Airy functions of suitable argument. On the other hand, if two of the zeros of F coalesce as $|\xi| \to \infty$ , then an approximation can be derived in terms of parabolic cylinder functions. In this paper we discuss both cases, but illustrate our technique in action by applying the parabolic cylinder case to the “classical” connection problem associated with the second Painlevé transcendent. Future papers will show how the technique can be applied with very little change to the other Painlevé equations, and to the wider problem of the asymptotic behavio ur of the general solution to any of these equations. [ABSTRACT FROM AUTHOR]

We study the dynamics of pattern formation in the one-dimensional partial differential equation proposed recently by Ball, Holmes, James, Pego & Swart [BHJPS] as a mathematical 'cartoon' for the dynamic formation of microstructures observed in various crystalline solids. Here W is a double-well potential like 1/4(( u) −1). What makes this equation interesting and unusual is that it possesses as a Lyapunov function a free energy (consisting of kinetic energy plus a nonconvex 'elastic' energy, but no interfacial energy contribution) which does not attain a minimum but favours the formation of finer and finer phase mixtures: Our analysis of the dynamics confirms the following surprising and striking difference between statics and dynamics, conjectured in [BHJPS] on the basis of numerical simulations of Swart & Holmes [SH]: Moreover, in order to understand the finer details of why the dynamics fails to mimic the behaviour of minimizing sequences and how solutions select their limiting pattern, we present a detailed analysis of the evolution of a restricted class of initial data - those where the strain field u has a transition layer structure; our analysis includes proofs that [ABSTRACT FROM AUTHOR]

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Objective: To evaluate the steady-state pharmacokinetics (PK) and dose proportionality of the selective 5-HT4 receptor partial agonist tegaserod (HTF 919) in healthy subjects. Methods: Eighteen subjects were given 2, 6, or 12-mg doses of tegaserod twice daily (b.i.d.) for 5 days, with PK and safety assessments made during the 12 h or 24 h following first administration, and 12 h after the final dose. Results: Tegaserod was rapidly absorbed [time to reach measured maximum plasma concentration after multiple administrations (tmax,ss) 1 h]. Steady-state PK were consistent with single-dose PK characteristics supporting that there was no accumulation of tegaserod in plasma based on systemic exposure. Mean measured maximum plasma concentration after multiple administrations (Cmax,ss) and area under the plasma concentration–time curve over one dosing interval (τ, 0–12 h after drug administration, AUCτ) were between 0.7±0.3 ng/ml and 5.6±2.9 ng/ml and 2.4±1.3 h·ng/ml and 20.4±14.0·h ng/ml, respectively, indicating dose-proportional PK of tegaserod in the range 2–12 mg b.i.d. Tegaserod was safe and well tolerated. No serious adverse events were reported. Conclusion: Tegaserod exhibits no accumulation and dose-proportional PK after multiple doses. [ABSTRACT FROM AUTHOR]

Crawlers of the new generation with environmentally friendly (magnetic) driving systems are described. A magnetic system for finding crawlers inside a pipe developed by the authors is described. Results of operational tests of crawlers equipped with the new driving system are given. [ABSTRACT FROM AUTHOR]

12-O-tetradecanoylphorbol-13-acetate (TPA, 1 to 30 ng/ml) produced a dose-related inhibition of substance P (SP)-induced histamine release from rat peritoneal mast cells. TPA itself induced some histamine release over this concentration range (maximum release about 20% of total). Maximum inhibition of SP-induced release by TPA required preincubation with TPA for at least 10 min. The inhibitory action of TPA was observed in the absence as well as in the presence of extracellular calcium (0.4 m M). Inhibition of diacylglycerol kinase by R 59022 or of diacylglycerol lipase by RHC 80267 reduced SP-induced histamine release. Oleolylacetylglycerol (OAG, 50 μ M) inhibited histamine release induced by SP but was less potent than TPA. It is concluded that protein kinase C activation in rat peritoneal mast cells is associated with inhibition of SP-induced histamine release. [ABSTRACT FROM AUTHOR]

Objective: The objective of the Children's Oral Health Initiative (COHI) is to increase access to preventive oral health services provided to First Nations and Inuit (FN/I) children living on federal reserves and in remote communities., Participants: COHI targets preschool children; 5-7-year-olds; pregnant women; and parents/caregivers in FN/I communities., Setting: The program was piloted in 2004 by Health Canada and is potentially available to all FN/I communities. However, the community must consent to the program's implementation and agree to support a community member to be trained as a COHI aide., Intervention: Dental therapists and hygienists screen eligible children, apply fluoride varnish and sealants to children's teeth, and stabilize active dental caries with glass ionomer. An innovation was the development of a community oral health worker, the COHI Aide. The COHI Aide is a community member who serves as an advocate for preventive oral health in the community and provides instruction to children, parent/caregivers and expectant mothers in preventing dental caries., Results: COHI was piloted in 41 communities in 2004. By 2014, the program had expanded to 320 FN/I communities, which represents 55% of all eligible FN/I communities. In 2012, 23,085 children had received COHI preventive oral health services., Conclusion: The results demonstrate COHI's success as a preventive oral health care delivery model in remote communities. Implementation and delivery of preventive oral health services has been enhanced by the sustained presence of a community-based COHI Aide.