bluuebunny/crossref_metadata_2025 huggingface dataset:
Spectrophotometric studies of rice bran oil and mustard oil mixtures: II
Authors: Jha J. S.
Published: July 2007

Visible spectra, between 400 to 500 nm range, of rice bran oil, mustard oil and their 7 mixtures, diluted 10 times in carbon tetrachloride, are reported. Mustard oil spectra shows three characteristic bands centered at wavelength 428, 453 and 482 nm, while no such band has been observed in rice bran oil spectra in this range. Intensity of 428 nm band increases as the rice bran oil percentage increases in the mixture of two oils. Five indices, R1 to R5, have been suggested for the approximate determination of rice bran oil adulteration in mustard oil. Plots of R2 and R3 against percentage of rice bran oil in the mixture have been found to be straight lines. The index R3, equal to 1000(A428‐A482), has been found to be the most useful for this approximate estimation of rice brain oil in mustard oil.
Cytoreductive Surgery and Intraperitoneal Chemohyperthermia for Chemoresistant and Recurrent Advanced Epithelial Ovarian Cancer: Prospective Study of 81 Patients
Authors: Cotte Eddy , Glehen Olivier , Mohamed Faheez , Lamy Franck , Falandry Claire , Golfier François , Gilly Francois Noel
Published: July 2007

Purpose

There is no standardized treatment for patients with chemoresistant or recurrent advanced ovarian cancer. Locoregional treatments combining cytoreductive surgery and intraperitoneal chemohyperthermia (HIPEC) may improve survival for locoregional disease.

Patients and methods

A prospective single center study of 81 patients with recurrent or chemoresistant peritoneal carcinomatosis from ovarian cancer was performed. Patients were treated by maximal cytoreductive surgery combined with HIPEC (with cisplatinum at 20 mg/m²/L). A total of 47 patients were included for their third, fourth, fifth, sixth, or seventh surgical look. Altogether, 54 patients presented with extensive carcinomatosis (malignant nodules of >5 mm).

Results

Complete macroscopic resection (CCR‐0) was achieved in 45 patients. Mortality and morbidity rates were 2.5% and 13.6%, respectively. With a median follow‐up of 47.1 months, the overall and disease‐free median survivals were 28.4 and 19.2 months, respectively. Carcinomatosis extent and completeness of cytoreduction (p = 0.02 and p <0.001, respectively) were identified as independent prognostic factors. For CCR‐0 patients, overall and disease‐free survivals were 54.9 and 26.9 months, respectively.

Conclusion

Salvage therapy combining optimal cytoreductive surgery and HIPEC may achieve long‐term survival in selected patients with recurrent or chemoresistant ovarian cancer. This strategy may be most effective in patients with limited carcinomatosis or when cytoreductive surgery provides sufficient downstaging.
Pilot‐plant fractionation of soybean glycinin and β‐conglycinin
Authors: Wu Shaowen , Murphy Patricia A. , Johnson Lawrence A. , Fratzke Alfred R. , Reuber Mark A.
Published: July 2007

A laboratory process for separating glycinin and β‐conglycinin from soybean flakes was successfully scaled up to the pilot‐plant scale (15 kg soy flakes). Average yields of the glycinin and β‐conglycinin fractions were both 9.4% on a dry basis (db). The protein contents of glycinin and β‐conglycinin fractions were 92.8 and 97.7% db, respectively. The glycinin and β‐conglycinin purities were 90.4 and 72.7% of the protein content, respectively, which were very comparable to those of the laboratory‐scale process. The total sulfhydryl plus half cystine content of the glycinin fraction was 37.8 mol/mol protein and 14.8 mol/mol protein for the β‐conglycinin fraction. The native glycinin structure loss in the glycinin fraction was negligible. The native β‐conglycinin loss in the β‐conglycinin fraction was 10%, as estimated by rocket immunoelectrophoresis analysis. Hydrophobicity index value showed that hydrophobic properties of the pilot‐plant protein fraction were ordered, from high to low: β‐conglycinin fraction > glycinin fraction > intermediate mixture fraction.
Effect of extraction conditions on sensory quality of virgin olive oil
Authors: Morales M. T. , Aparicio R.
Published: July 2007

The extraction conditions of virgin olive oil have a great influence on its sensory quality. During the centrifugation process, temperature and time of malaxing can be altered to potentially affect quality. Malaxing times (15, 30, 45, 60, and 90 min) and temperatures (25 and 35°C) were studied in an experimental oil mill. Volatile compounds, produced through the lipoxygenase pathway (hexanal, Z‐3‐hexenal, E‐2‐hexenal, hexyl acetate, Z‐3‐hexenyl acetate, hexan‐1‐ol, E‐3‐hexen‐1‐ol, Z‐3‐hexen‐1‐ol, and E‐2‐hexen‐1‐ol), were analyzed by dynamic headspace gas chromatography, gas chromatographymass spectrometry, and gas chromatography‐olfactometry. Different amounts of volatiles responsible for positive attributes of green aroma and negative attributes of astringent mouthfeel of virgin olive oil were determined. The results, after applying mathematical procedures, showed that a temperature of 25°C and a malaxing time between 30 and 45 min produced volatile compounds that contribute to the best sensory quality. High temperature (T≥35°C) with minimum values of time (t<30 min) could also be useful as an alternative way to obtain pleasant green virgin olive oils.
Effects of free fatty acids on oxidative stability of vegetable oil
Authors: Frega N. , Mozzon M. , Lercker G.
Published: July 2007

The effect of free fatty acid (FFA) content on the susceptibility to thermooxidative degeneration of vegetable oils was determined by Rancimat analysis. A prooxidant effect of FFA was observed in all filtered oils, independently of lipidic substrate and of its state of hydrolytic and oxidative alteration. The intensity of this effect was related to FFA concentration, but regression analysis of the experimental data did not show a general correlation law between FFA concentration and induction time (It). Different results were obtained for freshly processed virgin olive oils, characterized by postpressing natural suspension‐dispersion: opposite behavior was observed of FFA content as regards oxidative stability, depending on the presence of suspended‐dispersed material. This fact is of interest because the dispersed particles play a double stabilizing effect on both oxidative and hydrolytic degradation. These results showed that avoidance of oil filtration is highly desirable to extend olive oil's shelf life.
Effects of natural and synthetic antioxidants on changes in refined, bleached, and deodorized palm olein during deep‐fat frying of potato chips
Authors: Che Man Y. B. , Tan C. P.
Published: July 2007

The effects of antioxidants on the changes in quality characteristics of refined, bleached, and deodorized (RBD) palm olein during deep‐fat frying (at 180°C) of potato chips for 3.5 h/d for seven consecutive days in five systems were compared in this study. The systems were RBD palm olein without antioxidant (control), with 200 ppm butylated hydroxytoluene (BHT), 200 ppm butylated hydroxyanisole (BHA), 200 ppm oleoresin rosemary, and 200 ppm sage extract. Fried oil samples were analyzed for peroxide value (PV), thiobarbituric acid (TBA) value, iodine value (IV), free fatty acid (FFA) content, polymer content, viscosity, E1%1 cm at 232 and 268 nm, color, fatty acid composition, and C18:2/C16:0 ratio. Sensory quality of the potato chips fried in these systems prior to storage was also evaluated. The storage stability of fried potato chips for 14 wk at ambient temperature was also determined by means of the TBA values and sensory evaluation for rancid odor. Generally, in the oil, oleoresin rosemary gave the lowest rate of increase of TBA value, polymer content, viscosity, E1%1 cm at 232 and 268 nm compared to control and three other antioxidants. The order of effectiveness (P<0.05) in inhibiting oil oxidation in RBD palm olein was oleoresin rosemary > BHA > sage extract > BHT > control. Prior to storage, the sensory evaluation of fried potato chips for each system showed that there was no significant (P>0.05) difference in terms of flavor, odor, texture, and overall acceptability. The same order of effectiveness (P<0.05) of antioxidants was observed for storage stability study of fried potato chips by TBA values. However, there was no significant (P > 0.05) difference in sensory evaluation for rancid odor during storage periods.
Protein and the critically ill; do we know what to give?
Authors: Stroud Mike
Published: July 2007

The National Institute for Health and Clinical Excellence (NICE) has recommended that nutrition support in seriously-ill or injured patients should start at ⩽50% of the estimated target energy and protein needs. This recommendation has caused some concern, since taking the NICE approach leads to these sick individuals receiving an initial N provision of only ⩽0·12 g N/kg per d, as opposed to levels of approximately 0·25 g N/kg per d that have been widely recommended by other expert groups. The basis of the recommendation for higher levels of N provision is that feeding at levels of ≥0·25 g N/kg per d reduces the inevitable net N loss of catabolism and hence minimises overall lean tissue wasting. However, although it has always been assumed that better N balance must equate with better outcome, there are teleological arguments that question the wisdom of providing more N to sicker patients and studies that imply that best N balance might not equate with best clinical progress. Furthermore, current evidence suggests that in most critical illness low initial intakes of both energy and N lead to improved survival. It therefore seems logical to aim, in the first instance, to feed the seriously ill at only modest levels. Further research is required to determine whether lower-energy higher-N feeding would prove better or worse than this approach in terms of clinical benefit rather than just better N retention. Investigations to explore the use of feeds that are specifically designed to match the amino acid needs of illness are also required.
Session 1: Feeding and infant development Breast-feeding and immune function
Authors: Hanson Lars Å.
Published: July 2007

The newborn receives, via the placenta, maternal IgG antibodies against the microbes present in its surroundings, but such antibodies have a pro-inflammatory action, initiating the complement system and phagocytes. Although the host defence mechanisms of the neonate that involve inflammatory reactivity are somewhat inefficient, this defence system can still have catabolic effects. Breast-feeding compensates for this relative inefficiency of host defence in the neonate by providing considerable amounts of secretory IgA antibodies directed particularly against the microbial flora of the mother and her environment. These antibodies bind the microbes that are appearing on the infant's mucosal membranes, preventing activation of the pro-inflammatory defence. The major milk protein lactoferrin can destroy microbes and reduce inflammatory responses. The non-absorbed milk oligosaccharides block attachment of microbes to the infant's mucosae, preventing infections. The milk may contain anti-secretory factor, which is anti-inflammatory, preventing mastitis in mothers and diarrhoea in infants. Numerous additional factors in the milk are of unknown function, although IL-7 is linked to the larger size of the thymus and the enhanced development of intestinal Tγδ lymphocytes in breast-fed compared with non-breast-fed infants. Several additional components in the milk may help to explain why breast-feeding can reduce infant mortality, protecting against neonatal septicaemia and meningitis. It is therefore important to start breast-feeding immediately. Protection is also apparent against diarrhoea, respiratory infections and otitis media. There may be protection against urinary tract infections and necrotizing enterocolitis, and possibly also against allergy and certain other immunological diseases, and tumours. In conclusion, breast-feeding provides a very broad multifactorial anti-inflammatory defence for the infant.
Session 7: Early nutrition and later health Early developmental pathways of obesity and diabetes risk
Authors: Dunger D. B. , Salgin B. , Ong K. K.
Published: July 2007

Size at birth and patterns of postnatal weight gain have been associated with adult risk for the development of type 2 diabetes in many populations, but the putative pathophysiological link remains unknown. Studies of contemporary populations indicate that rapid infancy weight gain, which may follow fetal growth restriction, is an important risk factor for the development of childhood obesity and insulin resistance. Data from the Avon Longitudinal Study of Pregnancy and Childhood shows that rapid catch-up weight gain can lead to the development of insulin resistance, as early as 1 year of age, in association with increasing accumulation of central abdominal fat mass. In contrast, the disposition index, which reflects the β-cells ability to maintain insulin secretion in the face of increasing insulin resistance, is much more closely related to ponderal index at birth than postnatal catch-up weight gain. Infants with the lowest ponderal index at birth show a reduced disposition index at aged 8 years associated with increases in fasting NEFA levels. The disposition index is also closely related to childhood height gain and insulin-like growth factor-I (IGF-I) levels; reduced insulin secretory capacity being associated with reduced statural growth, and relatively short stature with reduced IGF-I levels at age 8 years. IGF-I may have an important role in the maintenance of β-cell mass, as demonstrated by recent studies of pancreatic β-cell IGF-I receptor knock-out and adult observational studies indicating that low IGF-I levels are predictive of subsequent risk for the development of type 2 diabetes. However, as insulin secretion is an important determinant of IGF-I levels, cause and effect may be difficult to establish. In conclusion, although rapid infancy weight gain and increasing rates of childhood obesity will increase the risk for the development of insulin resistance, prenatal and postnatal determinants of β-cell mass may ultimately be the most important determinants of an individual's ability to maintain insulin secretion in the face of increasing insulin resistance, and thus risk for the development of type 2 diabetes.
Comparison results for PDEs with a singular potential
Authors: Dávila Juan , Dupaigne Louis
Published: July 2007

Several comparison results are obtained for solutions to linear elliptic and parabolic equations with a singular potential. Solutions to these equations are singular in many cases, and our results roughly say that they all have comparable singularities, provided that they belong to an appropriate space. We formulate the hypothesis on the potential in terms of an inequality, which in the case of the well-known inverse-square potential, is a consequence of an improvement of Hardy's inequality due to Vázquez and Zuazua.
The projection of a rectifiable Legendrian set is C2-rectifiable: a simplified proof
Authors: Delladio Silvano
Published: July 2007

We provide a simplified proof of the following well-known theorem. The projection to Rn + 1of an n-dimensional rectifiable Legendrian subset of Rn+1 × Snis C2-rectifiable. Such a result generalizes the following simple fact. Let M be a hypersurface whose Gauss map has graph of class C1. Then M is of class C2.
Stability enhancement of output for a class of linear parabolic systems
Authors: Nambu Takao
Published: July 2007

In regular state stabilization of a class of linear parabolic systems, the number of the sensors wk and the actuators hk are required to be greater than or equal to the maximum of the multiplicities of the unstable eigenvalues. In this paper, we ask what control theoretic results we can establish with smaller numbers of wk and hk. The enhancement of stability of output or the output stabilization, a concept weaker than regular state stabilization, gives an answer to the question. Conditions of a fairly different nature than those for regular state stabilization appear; these are the rank conditions of the products of the observability and controllability matrices. The result is applied to a parabolic system with boundary observation/control via two different approaches.
Asymptotics toward the diffusion wave for a one-dimensional compressible flow through porous media
Authors: Nishihara Kenji
Published: July 2007

Consider the Cauchy problem for a one-dimensional compressible flow through porous media,

Hsiao and Liu showed that the solution (υ, u) behaves as the diffusion wave (ῡ, ū), i.e. the solution of the porous-media equation due to the Darcy law. The optimal convergence rates have been obtained by Nishihara and co-workers. When υ0(x) has the same constant state at x = ±∞, the convergence rate ‖(υ − ῡ)(·,t)‖L∞ = O(t−1) obtained is ‘optimal’, since ‖ῡ(·,t)‖∞ = O(t−1/2). However, this ‘optimal’ convergence rate is less sufficient to determine the location of the diffusion wave. Our aim in this paper is to obtain the ‘truly optimal’ convergence rate by choosing suitably located diffusion waves.
A remark on concentration of the error between a function and its best polynomial approximants
Authors: Zhou S. P.
Published: July 2007

By a new approach and different techniques, the present paper will give an essential generalization of a main theorem of Hasson. We also show that there do exist functions that satisfy the condition in our theorem, which we suggest to replace Hasson's condition (H1) or (H2) (for k = 1), but do not satisfy Hasson's condition. This gives a negative answer to a question raised by Hasson.
Constructing the symplectic Evans matrix using maximally analytic individual vectors
Authors: Bridges Thomas J. , Derks Gianne
Published: July 2007

For linear systems with a multi-symplectic structure, arising from the linearization of Hamiltonian partial differential equations about a solitary wave, the Evans function can be characterized as the determinant of a matrix, and each entry of this matrix is a restricted symplectic form. This variant of the Evans function is useful for a geometric analysis of the linear stability problem. But, in general, this matrix of two-forms may have branch points at isolated points, shrinking the natural region of analyticity. In this paper, a new construction of the symplectic Evans matrix is presented, which is based on individual vectors but is analytic at the branch points—indeed, maximally analytic. In fact, this result has greater generality than just the symplectic case; it solves the following open problem in the literature: can the Evans function be constructed in a maximally analytic way when individual vectors are used? Although the non-symplectic case will be discussed in passing, the paper will concentrate on the symplectic case, where there are geometric reasons for evaluating the Evans function on individual vectors. This result simplifies and generalizes the multi-symplectic framework for the stability analysis of solitary waves, and some of the implications are discussed.
Extensions of multilinear operators and Banach space properties
Authors: Gutiérrez Joaquín M. , Villanueva Ignacio
Published: July 2007

A new characterization of the Dunford–Pettis property in terms of the extensions of multilinear operators to the biduals is obtained. For the first time, multilinear characterizations of the reciprocal Dunford–Pettis property and Pełczyński's property (V) are also found. Polynomial and holomorphic versions of these properties are given as well.
On two functionals connected to the Laplacian in a class of doubly connected domains
Authors: Kesavan S.
Published: July 2007

Let B1 be a ball of radius R1 in RN with centre at the origin and let B0 be a smaller ball of radius R0 contained inside it. Let u be the solution of the problem −Δu = 1 in B1\B0 vanishing on the boundary. It is shown that

is minimal if and only if the balls are concentric. It is also shown that the first (Dirichlet) eigenvalue of the Laplacian in B1\B0 is maximal if and only if the balls are concentric. Generalizations are indicated.
Exact multiplicity for semilinear elliptic Dirichlet problems involving concave and convex nonlinearities
Authors: Tang Moxun
Published: July 2007

Let B be the unit ball in Rn, n ≥ 3. Let 0 < p < 1 < q ≤ (n + 2)/(n − 2). In 1994, Ambrosetti et al. found that the semilinear elliptic Dirichlet problem

admits at least two solutions for small λ > 0 and no solution for large λ. In this paper, we prove that there is a critical number Λ > 0 such that this problem has exactly two solutions for λ ∈ (0, Λ), exactly one solution for λ = Λ and no solution for λ > Λ.
Some beta-function inequalities
Authors: Alzer Horst
Published: July 2007

We present several new inequalities for Euler's beta function, B(x, y). One of our results states that the beta function can be approximated on (0, 1] × (0, 1] by rational functions as follows,

with the best possible constants α = 1 and β = ⅔π2 − 4 = 2.579 73 ….
On Povzner–Wienholtz-type self-adjointness results for matrix-valued Sturm–Liouville operators
Authors: Clark Steve , Gesztesy Fritz
Published: July 2007

We derive Povzner–Wienholtz-type self-adjointness results for m × m matrix-valued Sturm–Liouville operators

in L2((a, b);R dx)m, m ∈ N, for (a, b) a half-line or R.
Uniform asymptotic expansions for associated Legendre functions of large order
Authors: Dunster T. M.
Published: July 2007

Uniform asymptotic expansions are obtained for the associated Legendre functions and , and the Ferrers functions and , as the order μ → ∞. The approximations are uniformly valid for 0 ≤ ν + ½ ≤ μ(1 − δ), where δ ∈ (0, 1) is fixed, x ∈ (−1, 1) in the real-variable case and Re z ≥ 0 in the complex-variable case. Explicit error bounds are available for all approximations. In the complex-variable case, expansions are obtained by an application of two existing general asymptotic theories to the associated Legendre differential equation: the first case (in which ν is fixed) applies to regions containing an isolated simple pole; and the second case (in which 0 ≤ ν + ½ ≤ μ(1 − δ)) applies to regions containing a coalescing turning point and double pole. In both cases, the expansions involve modified Bessel functions. In the real-variable case (in which 0 ≤ ν + ½ ≤ μ(1 − δ)), asymptotic expansions of Liouville–Green type are obtained, which involve elementary functions.
Axial symmetry of solutions to semilinear elliptic equations in unbounded domains
Authors: Montefusco Eugenio
Published: July 2007

In this paper we study the problem of the axial symmetry of solutions of some semilinear elliptic equations in unbounded domains. Assuming that the solutions have Morse index one and that the nonlinearity is strictly convex in the second variable, we are able to prove several symmetry results in Rn and in the exterior of a ball. The case of some bounded domains is also discussed.
On an elliptic problem with boundary blow-up and a singular weight: the radial case
Authors: Chuaqui M. , Cortázar C. , Elgueta M. , Flores C. , Letelier R. , García-Melián J.
Published: July 2007

In this work we consider the non-autonomous problem Δu = a(x)um in the unit ball B ⊂ RN, with the boundary condition u|∂B = +∞, and m > 0. Assuming that a is a continuous radial function with a(x) ˜ C0 dist(x, ∂B)−γ as dist(x, ∂B) → 0, for some C0 > 0, γ > 0, we completely determine the issues of existence, multiplicity and behaviour near the boundary for radial positive solutions, in terms of the values of m and γ. The case 0 < m ≤ 1, as well as estimates for solutions to the linear problem m = 1, are a significant part of our results.
A counter-example in G-convergence of non-divergence elliptic operators
Authors: D'Onofrio Luigi , Greco Luigi
Published: July 2007

In a planar domain, to each function w ∈ W2,2 satisfying a suitable condition we associate a non-divergence elliptic differential operator 𝔏 such that 𝔏w = 0. For a given converging sequence {wk}, we study G-convergence of the corresponding sequence {𝔏k} of operators.
Topologically trivial holomorphic vector bundles on infinite-dimensional projective varieties
Authors: Ballico E.
Published: July 2007

Let V be an infinite-dimensional locally convex complex space, X a closed subset of P(V) defined by finitely many continuous homogeneous equations and E a holomorphic vector bundle on X with finite rank. Here we show that E is holomorphically trivial if it is topologically trivial and spanned by its global sections and in a few other cases.
Estimates for the energy of the solutions to elliptic Dirichlet problems on convex domains
Authors: Crasta Graziano
Published: July 2007

We provide an estimate of the energy of the solutions to the Poisson equation with constant data and Dirichlet boundary conditions in a convex domain Ω ⊂ Rn. This estimate is obtained by restricting the variational formulation of the problem to the space of functions depending only on the distance from the boundary of Ω. The main tool in the proof is an isoperimetric inequality for convex domains, which is a consequence of the Brunn-Minkowski theorem.
An existence result on positive solutions for a class of semilinear elliptic systems
Authors: Hai D. D. , Shivaji R.
Published: July 2007

Consider the system

where λ is a positive parameter and Ω is a bounded domain in RN. We prove the existence of a large positive solution for λ large when limx → ∞ (f(Mg(x))/x) = 0 for every M > 0. In particular, we do not need any monotonicity assumptions on f, g, nor any sign conditions on f(0), g(0).
Connection formulae for spectral functions associated with singular Dirac equations
Authors: Riehl S. M.
Published: July 2007

We consider the Dirac equation given by

with initial condition y1 (0) cos α + y2(0) sin α = 0, α ε [0; π ) and suppose the equation is in the limit-point case at infinity. Using to denote the derivative of the corresponding spectral function, a formula for is given when is known and positive for three distinct values of α. In general, if is known and positive for only two distinct values of α, then is shown to be one of two possibilities. However, in special cases of the Dirac equation, can be uniquely determined given for only two values of α.
Global and exponential attractors for nonlinear reaction–diffusion systems in unbounded domains
Authors: Efendiev M. , Miranville A. , Zelik S.
Published: July 2007

We study the long-time behaviour of solutions of autonomous and non-autonomous reaction-diffusion equations in unbounded domains of R3. It is shown that, under appropriate assumptions on the nonlinear interaction function and on the external forces, these equations possess compact global (uniform) attractors in the corresponding phase space. Estimates for Kolmogorov's ε-entropy of these attractors in terms of Kolmogorov's entropy of the external forces are given. Moreover, (infinite-dimensional) exponential attractors with the same entropy estimate as that of the corresponding global (uniform) attractor are also constructed.
Some elliptic semilinear indefinite problems on RN
Authors: Giacomoni Jacques , Lucia Marcello , Ramaswamy Mythily
Published: July 2007

This paper deals with the existence and the behaviour of global connected branches of positive solutions of the problem

The function f is allowed to change sign and has an asymptotically linear or a superlinear behaviour.
Strict convexity of level sets of solutions of some nonlinear elliptic equations
Authors: Gladiali Francesca , Grossi Massimo
Published: July 2007

In this paper we study the convexity of the level sets of solutions of the problem

where f is a suitable function with subcritical or critical growth. Under some assumptions on the Gauss curvature of ∂Ω, we prove that the level sets of the solution of (0.1) are strictly convex.
Asymptotic stability of travelling waves for Nicholson's blowflies equation with diffusion
Authors: Mei Ming , So Joseph W.-H. , Li Michael Y. , Shen Samuel S.P.
Published: July 2007

This paper considers the nonlinear stability oftravelling wavefronts of a time-delayed diffusive Nicholson blowflies equation. We prove that, under a weighted L2 norm, ifa solution is sufficiently close to a travelling wave front initially, it converges exponentially to the wavefront as t → ∞. The rate ofconvergence is also estimated.
Fixed points of composite meromorphic functions and normal families
Authors: Bergweiler Walter
Published: July 2007

We show that there exists a function f, meromorphic in the plane C, such that the family of all functions g holomorphic in the unit disc D for which f ∘ g has no fixed point in D is not normal. This answers a question of Hinchliffe, who had shown that this family is normal if Ĉ\f(C) does not consist of exactly one point in D. We also investigate the normality of the family of all holomorphic functions g such that f(g(z)) ≠ h(z) for some non-constant meromorphic function h.
On a heat problem involving the perturbed Hardy–Sobolev operator
Authors: Chaudhuri Nirmalendu , Sandeep Kunnath
Published: July 2007

Let Ω be a bounded domain in Rn, n ≥ 3 and 0 ∈ Ω. It is known that the heat problem ∂u/∂t + Lλ*u = 0 in Ω × (0, ∞), u(x, 0) = u0 ≥ 0, u0 ≢ 0, where Lλ* := −Δ − λ*/|x|2, λ* := ¼(n − 2)2, does not admit any solutions for any t > 0. In this paper we consider the perturbation operator Lλ*q := −Δ − λ*q(x)/|x|2 for some suitable bounded positive weight function q and determine the border line between the existence and non-existence of positive solutions for the above heat problem with the operator Lλ*q. In dimension n = 2, we have similar phenomena for the critical Hardy–Sobolev operator L* := −Δ − (1/4|x|2)(log R/|x|)−2 for sufficiently large R.
New additive results for the g-Drazin inverse
Authors: González N. Castro , Koliha J. J.
Published: July 2007

This paper studies additive properties of the generalized Drazin inverse (g-Drazin inverse) in a Banach algebra and finds an explicit expression for the g-Drazin inverse of the sum a + b in terms of a and b and their g-Drazin inverses under fairly mild conditions on a and b.
Existence and non-existence of global solutions of diffusion systems with nonlinear boundary conditions
Authors: Qi Yuanwei , Wang Mingxin , Wang Zejun
Published: July 2007

This paper deals with existence and non-existence of global solutions of certain fast–slow diffusion systems with nonlinear boundary conditions. Necessary and sufficient conditions for global existence of positive solutions are obtained in terms of various parameters which appear explicitly in the definition of the systems.
Oscillation and variation for the Gaussian Riesz transforms and Poisson integral
Authors: Harboure E. , Macías R. A. , Menárguez M. T. , Torrea J. L.
Published: July 2007

For the family of truncations of the Gaussian Riesz transforms and Poisson integral we study their rate of convergence through the oscillation and variation operators. More precisely, we search for their Lp (dγ)-boundedness properties, where dγ denotes the Gauss measure. We achieve our results by looking at the oscillation and variation operators from a vector-valued point of view.
Lp-estimates for the wave equation with time-dependent dissipation
Authors: Matsuyama Tokio
Published: July 2007

We are interested in Lp-estimates and scattering rates for the dissipative wave equation with time-dependent coefficients in an exterior domain outside a star-shaped obstacle. We want to notice the case that the support of dissipation expands strictly less than the wave speed. We develop a new cut-off method, which is time dependent. For this, we shall obtain the local energy decay over the time-dependent subdomain
Absence of high-energy spectral concentration for Dirac systems with divergent potentials
Authors: Eastham M. S. P. , Schmidt K. M.
Published: July 2007

It is known that one-dimensional Dirac systems with potentials q which tend to −∞ (or ∞) at infinity, such that 1/q is of bounded variation, have a purely absolutely continuous spectrum covering the whole real line. We show that, for the system on a half-line, there are no local maxima of the spectral density (points of spectral concentration) above some value of the spectral parameter if q satisfies certain additional regularity conditions. These conditions admit thrice-differentiable potentials of power or exponential growth. The eventual sign of the derivative of the spectral density depends on the boundary condition imposed at the regular end-point.
Very hyperbolic polynomials in one variable
Authors: Kostov Vladimir Petrov
Published: July 2007

A real polynomial in one real variable is called hyperbolic if it has only real roots. The polynomial f is called a primitive of order ν of the polynomial g if f(ν) = g. A hyperbolic polynomial is called very hyperbolic if it has hyperbolic primitives of all orders. In the paper we prove some geometric properties of the set D of values of the parameters ai for which the polynomial xn + a1xn−1 + … + an is very hyperbolic. In particular, we prove the Whitney property (the curvilinear distance to be equivalent to the Euclidean one) of the set D ∩{a1 = 0, a2 ≥ −1}.
A new proof of the characterization of the weighted Hardy inequality
Authors: Bernardis A. L. , Martí;n-Reyes F. J. , Salvador P. Ortega
Published: July 2007

Maz'ja and Sinnamon proved a characterization of the boundedness of the Hardy operator from Lp(v) into Lq(w) in the case 0 < q < p, 1 < p < ∞. We present here a new simple proof of the sufficiency part of that result.
Global continuation of nonlinear waves in a ring of neurons
Authors: Guo Shangjiang , Huang Lihong
Published: July 2007

In this paper, we consider a ring of neurons with self-feedback and delays. As a result of our approach based on global bifurcation theorems of delay differential equations coupled with representation theory of Lie groups, the coexistence of its asynchronous periodic solutions (i.e. mirror-reflecting waves, standing waves and discrete waves), bifurcated simultaneously from the trivial solution at some critical values of the delay, will be established for delay not only near to but also far away from the critical values. Therefore, we can obtain wave solutions of large amplitudes. In addition, we consider the coincidence of these periodic solutions.
Interval oscillation criteria for self-adjoint matrix Hamiltonian systems
Authors: Yang Qigui , Tang Yun
Published: July 2007

By using a monotonic functional on a suitable matrix space, some new oscillation criteria for self-adjoint matrix Hamiltonian systems are obtained. They are different from most known results in the sense that the results of this paper are based on information only for a sequence of subintervals of [t0, ∞), rather than for the whole half-line. We develop new criteria for oscillations involving monotonic functionals instead of positive linear functionals or the largest eigenvalue. The results are new, even for the particular case of self-adjoint second-differential systems which can be applied to extreme cases such as
Conical shock waves for an isentropic Euler system
Authors: Chen Shuxing , Li Dening
Published: July 2007

Conical shock waves are generated as sharp conical solid projectiles fly supersonically in the air. We study such conical shock waves in steady supersonic flow using an isentropic Euler system. The stability of such attached conical shock waves for non-symmetrical conical projectiles and non-uniform incoming supersonic flow is established. Meanwhile, the existence of the solution to the Euler system with such attached conical shock as a free boundary is also proved for solid projectiles close to a regular solid cone.
On convex representatives of polyconvex functions
Authors: Bevan Jonathan
Published: July 2007

The properties of convex representatives of polyconvex functions W : R2×2 → R are studied. The structure of the largest convex representative ϕW : R5 → R is given, and this is used to derive a representation formula for ϕW when W is C1 and satisfies a mild growth condition. The regularity of ϕW is discussed when W is C1; in particular, when W is C1, grows super-quadratically and is strictly polyconvex, it is shown that W has a C1 convex representative.
Continuous invertibility of minimal Sturm–Liouville operators in Lebesgue spaces
Authors: Brown R. C. , Cook J.
Published: July 2007

Using a standard theory of differential operators in Lebesgue spaces, we re-prove and generalize some results of Chernyavskaya and Shuster, giving (mostly sufficient) conditions that minimal operators determined by expressions of the form −(ry′)′ + qy with domain and range in possibly different Lp spaces on intervals with at least one singular endpoint have bounded inverses.
Integral and S-factorizable multilinear mappings
Authors: Cilia Raffaella , Gutiérrez Joaquın M.
Published: July 2007

We prove that several definitions of integral multilinear mappings given in the literature are equivalent. We show that what we call S-factorizable multilinear mappings are integral, but that the converse is not true (contrary to earlier claims). Using S-factorizable polynomials we give characterizations of L∞-spaces, Asplund spaces, spaces not containing ℓ1 and spaces with the compact range property. Some of these characterizations seem to be new even for linear operators.
A special case of the Sturm–Liouville inverse problem by three spectra: uniqueness results
Authors: Pivovarchik Vyacheslav
Published: July 2007

A three spectral inverse Sturm–Liouville problem is considered arising in the theory of vibrating strings. It is shown that in some special cases the solution of this problem is unique.
Zeta invariants for sequences of spectral type, special functions and the Lerch formula
Authors: Spreafico Mauro
Published: July 2007

We discuss the spectral properties of a class of sequences of what we call ‘spectral’ type. We introduce an effective method to calculate the zeta invariants for this type of sequence. Such invariants are given in terms of some new and old special functions, and we consider a number of examples in which we study the properties of these special functions.
Hardy's inequalities for monotone functions on partly ordered measure spaces
Authors: Arcozzi Nicola , Barza Sorina , Garcia-Domingo J. L. , Soria Javier
Published: July 2007

We characterize the weighted Hardy inequalities for monotone functions in In dimension n = 1, this recovers the standard theory of Bp weights. For n > 1, the result was previously only known for the case p = 1. In fact, our main theorem is proved in the more general setting of partly ordered measure spaces.
Bigraded structures and the depth of blow-up algebras
Authors: Colomé-Nin Gemma , Elias Juan
Published: July 2007

Let R be a Cohen–Macaulay local ring, and let I ⊂ R be an ideal with minimal reduction J. In this paper we attach to the pair (I, J) a non-standard bigraded module ΣI, J. The study of the bigraded Hilbert function of ΣI, J allows us to prove an improved version of Wang's conjecture and a weak version of Sally's conjecture, both on the depth of the associated graded ring grI(R). The module ΣI, J can be considered as a refinement of the Sally module introduced previously by Vasconcelos.
High burden of invasive β-haemolytic streptococcal infections in Fiji
Authors: STEER A. C. , JENNEY A. J. W. , OPPEDISANO F. , BATZLOFF M. R. , HARTAS J. , PASSMORE J. , RUSSELL F. M. , KADO J. H. H. , CARAPETIS J. R.
Published: July 2007

We undertook a 5-year retrospective study of group A streptococcal (GAS) bacteraemia in Fiji, supplemented by a 9-month detailed retrospective study of β-haemolytic streptococcal (BHS) infections. The all-age incidence of GAS bacteraemia over 5 years was 11·6/100 000. Indigenous Fijians were 4·7 times more likely to present with invasive BHS disease than people of other ethnicities, and 6·4 times more likely than Indo-Fijians. The case-fatality rate for invasive BHS infections was 28%. emm-typing was performed on 23 isolates: 17 different emm-types were found, and the emm-type profile was different from that found in industrialized nations. These data support the contentions that elevated rates of invasive BHS and GAS infections are widespread in developing countries, and that the profile of invasive organisms in these settings reflects a wide diversity of emm-types and a paucity of types typically found in industrialized countries.
Estimating the coverage of a targeted mobile tuberculosis screening programme among illicit drug users and homeless persons with truncated models
Authors: VAN HEST N. A. H. , De VRIES G. , SMIT F. , GRANT A. D. , RICHARDUS J. H.
Published: July 2007

Truncated models are indirect methods to estimate the size of a hidden population which, in contrast to the capture–recapture method, can be used on a single information source. We estimated the coverage of a tuberculosis screening programme among illicit drug users and homeless persons with a mobile digital X-ray unit between 1 January 2003 and 31 December 2005 in Rotterdam, The Netherlands, using truncated models. The screening programme reached about two-third of the estimated target population at least once annually. The intended coverage (at least two chest X-rays per person per year) was about 23%. We conclude that simple truncated models can be used relatively easily on available single-source routine data to estimate the size of a population of illicit drug users and homeless persons. We assumed that the most likely overall bias in this study would be overestimation and therefore the coverage of the targeted mobile tuberculosis screening programme would be higher.
Dose- and time-dependent effects of TNFα and actinomycin D on cell death incidence and embryo growth in mouse blastocysts
Authors: Fabian D. , Juhás S. , Il'ková G. , Koppel J.
Published: July 2007

This study was undertaken to obtain information about characteristics of different types of induced apoptosis in preimplantation embryos. Freshly isolated mouse blastocysts were culturedin vitrowith the addition of two apoptotic inductors – TNFα and actinomycin D – at various doses and times. The average number of nuclei and the percentage of dead cells were evaluated in treated embryos. Classification of dead cells was based on morphological assessment of their nuclei evaluated by fluorescence microscopy, the detection of specific DNA degradation (TUNEL assay), the detection of active caspase-3 and cell viability assessed by propidium iodide staining. The addition of both apoptotic inductors into culture media significantly increased cell death incidence in blastocysts. Their effects were dose and time dependent. Lower concentrations of inductors increased cell death incidence, usually without affecting embryo growth after 24 h culture. Higher concentrations of inductors caused wider cell damage and also retarded embryo development. In all experiments, the negative effect of actinomycin D on blastomere survival and blastocyst growth was greater than the effect of TNFα. Furthermore, the addition of actinomycin D into culture media increased cell death incidence even after 6 h culture. Differences resulted probably from diverse specificity of apoptotic inductors. The majority of dead cells in treated blastocysts were of apoptotic origin. Morphological and biochemical features of apoptotic cell death induced by both TNFα and actinomycin D were similar and had homologous profile. In blastomeres, similarly to somatic cells, the biochemical pathways of induced apoptosis included activation of caspase-3 and internucleosomal DNA fragmentation.
UN NATURAL HISTORY: WARD'S GLASS CASES
Authors: Darby Margaret Flanders
Published: July 2007

IN 1829, NATHANIEL BAGSHAW WARD buried a sphinx moth chrysalis in some soil – he called it “mould” – in a closed glass bottle. While he waited to observe the insect's metamorphosis, his attention shifted to something quite unintended and unexpected: a tiny fern and a few blades of grass emerged in the mould and continued to grow without the addition of more water to the bottle. Thanks to this diminutive event, an unsuccessful gardener was empowered, and his frustrated desire was liberated into a genesis story of radical potential in the least forgiving of circumstances.
Measurement of Cation Exchange Capacity (CEC) of Plant Cell Walls by X-Ray Microanalysis (EDX) in the Transmission Electron Microscope
Authors: Fritz Eberhard
Published: July 2007

Cation exchange capacity (CEC) characterizes the number of fixed negative charges of plant cell walls and is an important parameter in studies dealing with the uptake of ions into plant tissues, especially in roots. Conventional methods of CEC determination use bulk tissue, the results are the mean of many cells, and differences in the CEC of different tissue types are masked. Energy-dispersive microanalysis (EDX) in the transmission electron microscope allows CEC determinations on much finer scales. Shoot and fine root tissue ofPicea abieswas acid washed to remove exchangeable cations. Tissue blocks or semithin tissue sections were loaded with 0.2 mM CaCl2, AlCl3, or Pb(NO3)2at pH 4.0. The amount of Ca, Al, or Pb adsorbed to the exchange sites of cell walls was determined by EDX. The CEC of cell walls of different tissue types was highly different, ranging in shoot tissues from 0 to 856 mM Ca and 5.8 to 1463 mM Al (block loading) or 4.3 to 1116 mM Ca and 0 to 2830 mM Al (section loading). In root tissue, Pb adsorption to semithin sections yielded CEC values between 29.1 and 954 mM Pb. In mostP. abiesshoot tissues, the binding capacity was clearly higher for Al than for Ca.
Polyamine analogues: potent inducers of nucleosomal array oligomerization and inhibitors of yeast cell growth
Authors: Carruthers Lenny M. , Marton Laurence J. , Peterson Craig L.
Published: July 2007

Polyamines are naturally occurring intracellular polycations that are essential for viability and growth of eukaryotes. Dysregulation of polyamine metabolism is a hallmark of cancer and the carcinogenic process, and consequently development of polyamine analogues has emerged as a viable strategy for therapeutic intervention. Previously, we showed that the naturally occurring polyamines spermidine and spermine were quite effective at inducing the oligomerization of nucleosomal arrays in vitro, suggesting that polyamines may play a key role in regulating higher order chromatin structures in vivo. Here, we analyse the ability of a number of synthetic polyamine analogues to potentiate formation of higher order chromatin structures in vitro. We find that a class of long-chain polyamines called oligoamines are potent inducers of nucleosomal array oligomerization in vitro and that these same polyamine analogues rapidly block yeast cell growth.
Effects of pro-opiomelanocortin (POMC) on food intake and body weight: mechanisms and therapeutic potential?
Authors: Coll Anthony P.
Published: July 2007

POMC (pro-opiomelanocortin) is a complex polypeptide precursor which is cleaved into smaller biologically active peptides such as the melanocortins, α-, β- and γ-melanocyte-stimulating hormone. Data from human genetic and murine studies convincingly show that an intact central melanocortin signalling pathway is critical for normal energy homoeostasis. Not only does a loss of normal melanocortin signalling lead to obesity, but there are also data implicating increased melanocortin activity in the pathogenesis of cachexia. The study of POMC biology has lead to some fundamental insights into the mechanisms controlling food intake and body weight. This increased understanding of the physiological roles of the melanocortin system has opened up the potential for the design and development of rational therapies to treat perturbations in energy homoeostasis.