bluuebunny/crossref_metadata_2025 huggingface dataset:
Phenolic acids in rapeseed and mustard
Authors: Kozlowska H. , Rotkiewicz D. A. , Zadernowski R. , Sosulski F. W.
Published: July 2007

The compositions of free phenolic acids in rapeseed flours of diverse origin and white mustard were highly variable but represented less than 10% of the total phenolic acids. Phenolic acids released from hydrolysis of soluble esters constituted the major fraction, with Polish varieties having higher levels than a Canadian variety or white mustard. Yellow Sarson contained low levels of phenolic acids. Sinapic acid isomers constituted over 94% of the 13 phenolic acids found in the rapeseed varieties. Only traces of several phenolic acids appeared to be structurally bound to rapeseed and mustard proteins and carbohydrates.
Analysis of sorbitan fatty acid esters by HPLC
Authors: Garti N. , Wellner E. , Aserin A. , Sarig S.
Published: July 2007

Sorbitan esters of several fatty acids have been analyzed by high pressure liquid chromatography (HPLC) using an RP‐18 column. No derivatization was necessary. Mono‐, di‐ and trisorbitan esters of palmitic, stearic, oleic, isostearic and sesquioleic acid have been separated using isopropanol/water as the elution mixture.
Hydrogen sulfide adducts of methyltrans,trans‐ 9,11‐octadecadienoate
Authors: Schwab A. W. , Rohwedder W. K. , Gast L. E.
Published: July 2007

Hydrogen sulfide was added to methyltrans, trans‐ 9,11‐octadecadienoate in benzene solution at 25 C with ultraviolet radiation. GC‐MS and GLC analysis of the reaction product showed the presence of methyl oleate, methyl stearate, geometric isomers of methyl 9,11‐octadecadienoate, methyl 9,12‐epoxy‐octadeca‐9, 11‐dienoate, an unknown compound with an apparent molecular weight of 306, methyl 8‐(2′,5′‐hexylthienyl) octanoate, an unidentified sul‐fur] containing C18 ester with an apparent molecular weight of 326, methyl 9,12‐epithiostearate, an adduct of methyltrans,trans‐ 9,11‐octadecadienoate and ben‐zene [bicyclo (4.4.0)‐deca‐2,5,7‐triene‐l‐(Ω‐carboxy‐methyl heptyl)‐4 hexyl] and a probable mixture of methyl 9,11‐epidithiostearate, methyl 9,12‐epidithio‐stearate, and methyl 10,12‐epidithiostearate.
Stability of emulsions containing sucrose esters
Authors: Osipow Lloyd , Snell Foster Dee , Ferencz Murray
Published: July 2007

Conclusions

The presence of either sucrose distearate or glyceryl monostearate will decrease the stability of preformed mineral oil‐in‐water emulsions containing sucrose monostearate. With adequate concentrations of emulsifier present the emulsion stability of milled emulsions passes through a maximum as the ratio of glyceryl monostearate to sucrose monostearate is increased. The data suggest that this increased stability results from a decrease in droplet size rather than from the formation of a more tenuous interfacial film.
Loss of fatty acid esters from grape surfaces during drying
Authors: Stafford A. E. , Fuller G. , Bolin H. R.
Published: July 2007

Fatty acid esters have been shown to reduce the drying time of grapes by interacting with the waxy surface of the grapes. Laboratory scale procedures were developed to determine the fate of esters during dehydration. Thompson seedless grapes were dipped in a water emulsion containing 2% fatty acid ester, 2% potassium carbonate and an emulsifier. Grapes were dried at ambient, 43 C and 71 C. Drying rates vs. fatty acid ester concentration on the grape surfaces were plotted. The fate of fatty acid esters during dehydration was determined by running the dryer exhaust through a cold trap and extracting the condensate. These studies showed that the large loss of esters during drying lowered the drying rate considerably. An additional dip during drying reduced the drying time significantly. The ester losses appeared to be caused by vapor distillation of the esters during drying.
“Sandwich” Plating for Intra-articular Distal Radius Fractures with Volar and Dorsal Metaphyseal Comminution
Authors: Day Charles S. , Kamath Atul F. , Makhni Eric , Jean-Gilles Jerome , Zurakowski David
Published: July 2007

Introduction Intra-articular distal radius fractures with volar and dorsal comminution present a special challenge to the hand surgeon.

Methods Ten patients formed the study cohort. All plates were low profile and stainless steel. Radiographic parameters, range of motion, and strength compared to the uninjured side were recorded. Functional outcome was evaluated by Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire and Gartland and Werley scoring system.

Results Median age at surgery was 58 years (range, 24 to 86). Mean follow-up was 17 months (range, 12 to 28). According to the AO classification system, there were three type C2 and seven type C3 fractures. Median preoperative dorsal angulation was 24 deg; median postoperative dorsal angulation was 3 deg. Eighty percent (8) of the fractures also had an intra-articular step-off or gap, all of which were corrected to neutral by the procedure. Compared with the contralateral side, mean extension and flexion were 73 and 75%, respectively, pronation and supination were 95 and 88%, respectively, and grip strength and thumb pinch were 72 and 87%, respectively. Mean postoperative DASH score was 16 points, and 70% (7) of the patients had Gartland and Werley scores of good or excellent. None of the patients needed to have their plates removed, and no extensor tendon rupture was reported.

Conclusions The “sandwich” plating technique is an effective method of regaining near-anatomic reconstruction of intra-articular, volarly and dorsally comminuted distal radius fractures. Results from this study demonstrate that patients can expect to regain about 80% of their range of motion and strength. Moreover, 70% of the patients will have good to excellent functional outcomes. This is the first study to examine range of motion and functional outcome of low-profile “sandwich” plating without plate removal.
The lindlar‐catalyzed reduction of methyl santalbate: a facile preparation of methyl 9‐cis,11‐trans‐Octadecadienoate‐9,10‐d2
Authors: Adlof Richard O.
Published: July 2007

Conjugated linoleic acid (CLA) has been associated with the reduction of chemically induced cancers in mice and rats and the suppression of atherosclerosis in rats. We have found seed oils to be a valuable source of precursors for the rapid preparation of gram quantities of deuterium‐labeled fats. Methyl santalbate (methyl 11‐trans‐octadecen‐9‐ynoate), obtained from Santalum album (Linn.) seed, was reduced with Lindlar catalyst, quinoline, and deuterium gas to produce, in yields of 65–75%, the gram quantities of methyl 9‐cis,11‐trans‐octadecadienoate‐9,10‐d2 (CLA‐d2) we required for metabolism and oxidation studies. Unlike monoacetylenic and methylene‐interrupted polyacetylenic fatty acid methyl esters, the conjugated system was reduced with no noticeable break in the rate of deuterium uptake. The quantity of poison (quinoline) present did influence the amount of CLA‐d2 produced, but the production of overreduced fatty acid methyl esters (perhaps because of the conjugated system) could not be prevented. Fractionation of the reaction mixture by silver resin chromatography resulted in the isolation of >99% chemically pure CLA‐d2 in yields of 60–70%.
Effects of dietary retinoids and carotenoids on immune development
Authors: Rühl Ralph
Published: July 2007

Carotenoids and retinoids are groups of nutritionally-relevant compounds present in many foods of plant origin (carotenoids) and animal origin (mainly retinoids). Their levels in human subjects vary depending on the diversity and amount of the individual's nutrient intake. Some carotenoids and retinoids have been investigated for their effects on the immune system bothin vitroandin vivo. It has been shown that retinoids have the potential to mediate or induce proliferative and differentiating effects on several immune-competent cells, and various carotenoids are known to be inducers of immune function. The immune-modulating effects of retinoids have been well documented, while the effects of carotenoids on the immune system have not been investigated as extensively, because little is known about their molecular mechanism of action. The present review will mainly focus on the molecular mechanism of action of retinoids and particularly carotenoids, their nutritional origin and intake, their transfer from the maternal diet to the child and their effects or potential effects on the developing immune system.
Bendixson's criterion for systems with non-C1 vector fields
Authors: Hou Zhanyuan
Published: July 2007

The generalized Bendixson's criterion for non-existence of non-constant periodic solutions of an autonomous system dx/dt = f(x), x ∈ D, is further extended to systems when the condition f ∈ C1(D, RN) is violated. In particular, the criterion can be applied to region-wise linear systems in RN.
Constructing an operator from a complete and minimal set
Authors: Nath Jiban
Published: July 2007

Let be a complete and minimal set in a Hilbert space X, which is not an unconditional basis. Then there exists an operator that is densely defined on X, does not have a good spectral behaviour and all the vectors {ei} are its eigenvectors.
Rough isometry and energy-finite solutions for the Schrödinger operator on Riemannian manifolds
Authors: Kim Seok Woo , Lee Yong Hah
Published: July 2007

In this paper, we prove that the dimension of the space of bounded energy-finite solutions for the Schrödinger operator is invariant under rough isometries between complete Riemannian manifolds satisfying the local volume condition, the local Poincaré inequality and the local Sobolev inequality. We also prove that the dimension of the space of bounded harmonic functions with finite Dirichlet integral is invariant under rough isometries between complete Riemannian manifolds satisfying the same local conditions. These results generalize those of Kanai, Grigor'yan, the second author, and Li and Tam.
Pencils of differential operators containing the eigenvalue parameter in the boundary conditions
Authors: Marletta Marco , Shkalikov Andrei , Tretter Christiane
Published: July 2007

The paper deals with linear pencils N − λP of ordinary differential operators on a finite interval with λ-dependent boundary conditions. Three different problems of this form arising in elasticity and hydrodynamics are considered. So-called linearization pairs (W, T) are constructed for the problems in question. More precisely, functional spaces W densely embedded in L2 and linear operators T acting in W are constructed such that the eigenvalues and the eigen- and associated functions of T coincide with those of the original problems. The spectral properties of the linearized operators T are studied. In particular, it is proved that the eigen- and associated functions of all linearizations (and hence of the corresponding original problems) form Riesz bases in the spaces W and in other spaces which are obtained by interpolation between D(T) and W.
Estimates of averages of Fourier transforms with respect to general measures
Authors: Sjölin Per , Soria Fernando
Published: July 2007

We study a connection between the L2 average decay of the Fourier transform of functions with respect to a given measure and the Hausdorff behaviour of that measure.
Stability of scalar delay differential equations with dominant delayed terms
Authors: Tang X. H. , Zou Xingfu
Published: July 2007

This paper deals with scalar delay differential equations with dominant delayed terms. Sufficient conditions are obtained for uniform stability, uniformly asymptotic stability and globally asymptotic stability of the equations. The criteria extend and improve some existing ones. The main results are applied to two physiological models. Some counterexamples are also given to show the invalidity of some existing results.
Bifurcation results for semilinear elliptic problems in RN
Authors: Badiale Marino , Pomponio Alessio
Published: July 2007

In this paper we obtain, for a semilinear elliptic problem in RN, families of solutions bifurcating from the bottom of the spectrum of −Δ. The problem is variational in nature and we apply a nonlinear reduction method that allows us to search for solutions as critical points of suitable functionals defined on finite-dimensional manifolds.
Multiple solutions for a non-homogeneous elliptic equation at the critical exponent
Authors: Clapp Mónica , Del Pino Manuel , Musso Monica
Published: July 2007

We consider the equation−Δu = |u|4/(N−2)u + εf(x) under zero Dirichlet boundary conditions in a bounded domain Ω in RN exhibiting certain symmetries, with f ≥ 0, f ≠ 0. In particular, we find that the number of sign-changing solutions goes to infinity for radially symmetric f, as ε → 0 if Ω is a ball. The same is true for the number of negative solutions if Ω is an annulus and the support of f is compact in Ω.
On a singularly perturbed wave equation with dynamic boundary conditions
Authors: Popescu Luminiţa , Rodriguez-Bernal Aníbal
Published: July 2007

In this paper we analyse a singular perturbation problem for linear wave equations with interior and boundary damping. We show how the solutions converge to the formal parabolic limit problem with dynamic boundary conditions. Conditions are given for uniform convergence in the energy space.
Stability of steady states and existence of travelling waves in a vector-disease model
Authors: Ruan Shigui , Xiao Dongmei
Published: July 2007

In this paper, a host-vector model is considered for a disease without immunity in which the current density of infectious vectors is related to the number of infectious hosts at earlier times. Spatial spread in a region is modelled in the partial integro-differential equation by a diffusion term. For the general model, we first study the stability of the steady states using the contracting-convex-sets technique. When the spatial variable is one dimensional and the delay kernel assumes some special form, we establish the existence of travelling wave solutions by using the linear chain trick and the geometric singular perturbation method.
Mumford–Shah-type functionals associated with doubling metric measures
Authors: Baldi Annalisa , Franchi Bruno
Published: July 2007

In this paper we study Mumford–Shah-type functionals associated with doubling metric measures or strong A∞ weights in the setting of the perimeter theory in the sense of Ambrosio and Miranda in metric spaces. We prove an existence theorem in a suitably defined class of special BV functions.
On Fredholm properties of Lu = u′ − A(t)u for paths of sectorial operators
Authors: di Giorgio Davide , Lunardi Alessandra
Published: July 2007

We consider a path of sectorial operators t ↦ A (t) ∈ Cα (R, L (D, X)), 0 < α < 1, in general Banach space X, with common domain D (A (t)) = D and with hyperbolic limits at ±∞. We prove that there exist exponential dichotomies in the half-lines (−∞, −T] and [T, +∞) for large T, and we study the operator (Lu)(t) = u′(t) − A(t)u(t) in the space Cα (R, D) ∩ C1+α (R, X). In particular, we give sufficient conditions in order that L is a Fredholm operator. In this case, the index of L is given by an explicit formula, which coincides to the well-known spectral flow formula in finite dimension. Such sufficient conditions are satisfied, for instance, if the embedding D ↪ X is compact.
Multiple positive solutions for a nonlinear Dirichlet problem with non-convex vector-valued response
Authors: Nowakowski Andrzej , Rogowski Andrzej
Published: July 2007

In this paper we establish the existence of many positive solutions to

with Vx a vector-valued nonlinearity.
Structure of boundary blow-up solutions for quasilinear elliptic problems I. Large and small solutions
Authors: Guo Zongming , Webb J. R. L.
Published: July 2007

Existence and uniqueness of large, boundary blow-up solutions are obtained for the quasilinear elliptic problem −Δpu = λf(u) in Ω, u = ∞ on ∂Ω via good boundary layer estimates for large λ, where Δp is the p-Laplacian (1 < p < ∞) and Ω ⊂ R N (N ≥ 2) is a bounded smooth domain. The nonlinear term f satisfies f(0) = f(z1) = f(z2) = 0 with 0 < z1 < z2, with z2 a zero of f of order k. It is shown that, if k ≥ p −1, the unique large solution ūλ is a boundary-layer solution which satisfies ūλ > z2 in Ω; if 0 < k < p −1, the unique large solution ūλ is a boundary-layer solution, but a flat core of ūλ occurs. Furthermore, for sufficiently large λ a small positive boundary blow-up solution is obtained and its asymptotic behaviour as λ → ∞ is discussed.
Travelling waves for a reaction–diffusion system in population dynamics and epidemiology
Authors: Ai Shangbing , Huang Wenzhang
Published: July 2007

The existence and uniqueness of travelling-wave solutions is investigated for a system of two reaction–diffusion equations where one diffusion constant vanishes. The system arises in population dynamics and epidemiology. Travelling-wave solutions satisfy a three-dimensional system about (u, u′, ν), whose equilibria lie on the u-axis. Our main result shows that, given any wave speed c > 0, the unstable manifold at any point (a, 0, 0) on the u-axis, where a ∈ (0, γ) and γ is a positive number, provides a travelling-wave solution connecting another point (b, 0, 0) on the u-axis, where b:= b(a) ∈ (γ, ∞), and furthermore, b(·): (0, γ) → (γ, ∞) is continuous and bijective
Proof of the Chen–Rubin conjecture
Authors: Alzer Horst
Published: July 2007

Let n ≥ 0 be an integer and let λ(n) be the median of the Gamma distribution of order n + 1 with parameter 1. In 1986, Chen and Rubin conjectured that n ↦ λ (n) − n (n = 0, 1, 2, …) is decreasing. We prove the following monotonicity theorem, which settles this conjecture.

Let α and β be real numbers. The sequence n ↦ λ (n) – αn (n = 0, 1, 2, …) is strictly decreasing if and only if α; ≥ 1. And n ↦ λ(n) − βn (n = 0, 1, 2, …) is strictly increasing if and only if β < λ(1) − log 2 = 0.98519….
Morrey–Campanato estimates for Helmholtz equations with two unbounded media
Authors: Fouassier Elise
Published: July 2007

We prove uniform Morrey–Campanato estimates for Helmholtz equations in the case of two unbounded inhomogeneous media separated by an interface. They imply weighted L2-estimates for the solution. We also prove a uniform L2-estimate without weight for the trace of the solution on the interface.
Volume, energy and generalized energy of unit vector fields on Berger spheres: stability of Hopf vector fields
Authors: Gil-Medrano Olga , Hurtado Ana
Published: July 2007

We study to what extent the known results concerning the behaviour of Hopf vector fields, with respect to volume, energy and generalized energy functionals, on the round sphere are still valid for the metrics obtained by performing the canonical variation of the Hopf fibration.
Composition operators on Bloch-type spaces
Authors: Hu Zhangjian , Wang Shushi
Published: July 2007

We characterize those holomorphic symbols ϕ: D → D for which the induced composition operator Cϕ: Bω → Bμ (respectively, Bω,0 → Bμ,0) is bounded or compact, where D is the unit disc in the complex plane C, ω is a normal function on [0, 1) and μ is a non-negative function on [0, 1) with μ(tn) > 0 for some sequence satisfying limn→∞tn= 1.
On Hilbert and quaternionic cusp forms
Authors: Arenas A.
Published: July 2007

The aim of this paper is to determine in a natural manner the subspace of the space of Hilbert modular newforms of level n which correspond to eigenforms of an appropriate quaternion algebra, in the sense of having the same eigenvalues with respect to the corresponding Hecke operators. This study may be seen as a particular case of the Jacquet–Langlands correspondence.
On the quasi-nodal map for the Sturm–Liouville problem
Authors: Cheng Y. H. , Law C. K.
Published: July 2007

We show that the space of Sturm–Liouville operators characterized by H = (q, α, β) ∈ L1 (0, 1) × [0, π)2 such that is homeomorphic to the partition set of the space of all admissible sequences which form sequences that converge to q, α, and β individually. This space, Γ, of quasi-nodal sequences is a superset of, and is more natural than, the space of asymptotically nodal sequences defined in Law and Tsay (On the well-posedness of the inverse nodal problem. Inv. Probl.17 (2001), 1493–1512). The definition of Γ relies on the L1 convergence of the reconstruction formula for q by the exactly nodal sequence.
Existence of solutions of the prescribed mean-curvature equation on unbounded domains
Authors: Jin Zhiren
Published: July 2007

The existence of solutions of the Dirichlet problems for the prescribed mean-curvature equation on some unbounded domains in Rn(n ≥ 2) is proved. The results are proved using a modified version of the Perron method, where a subsolution is a solution to the minimal surface equation, while a supersolution is not constructed; instead, the role played by a supersolution is replaced by the estimates on the uniform bounds on the liftings of subfunctions on compact sets.
3D–2D analysis of a thin film with periodic microstructure
Authors: Babadjian Jean-François , Baía Margarida
Published: July 2007

In this article we study the behaviour of a heterogeneous thin film whose microstructure oscillates on a scale that is comparable to that of the thickness of the domain. The argument is based on a three-dimensional–two-dimensional reduction through a Γ-convergence analysis, techniques of two-scale convergence and a decoupling procedure between the oscillating variable and the in-plane variable.
On maps that preserve orthogonality in normed spaces
Authors: Blanco A. , Turnšek A.
Published: July 2007

We show that every orthogonality-preserving linear map between normed spaces is a scalar multiple of an isometry. Using this result, we generalize Uhlhorn's version of Wigner's theorem on symmetry transformations to a wide class of Banach spaces.
Branches of solutions to semilinear biharmonic equations on RN
Authors: Deng Yinbin , Li Yi
Published: July 2007

For a large class of functions f, we consider the nonlinear biharmonic eigenvalue problem

We describe the behaviour of the branch of solutions emanating from an eigenvalue of odd multiplicity below the essential spectrum of the linearized problem. The discussion is based on the degree theory for C2 proper Fredholm maps developed by Fitzpatrick, Pejsachowicz and Rabier.
Wave pinning in strips
Authors: Matthies Karsten , Wayne C. E.
Published: July 2007

We consider the existence of stationary or pinned waves of reaction–diffusion equations in heterogeneous media. By combining averaging, homogenization and dynamical-systems techniques we prove under mild non-degeneracy conditions that if the heterogeneity is periodic with period ε, pinned solutions persist at most for intervals in parameter space whose length is O(e−c/√ε).
Entire solutions of reaction—diffusion equations with balanced bistable nonlinearities
Authors: Chen Xinfu , Guo Jong-Shenq , Ninomiya Hirokazu
Published: July 2007

This paper deals with entire solutions of a bistable reaction—diffusion equation for which the speed of the travelling wave connecting two constant stable equilibria is zero. Entire solutions which behave as two travelling fronts approaching, with super-slow speeds, from opposite directions and annihilating in a finite time are constructed by using a quasi-invariant manifold approach. Such solutions are shown to be unique up to space and time translations.
Periodic solutions for equations with distributed delays
Authors: Lin Guojian , Yuan Rong
Published: July 2007

A general theorem about the existence of periodic solutions for equations with distributed delays is obtained by using the linear chain trick and geometric singular perturbation theory. Two examples are given to illustrate the application of the general the general therom.
THE LITERARY PORTRAIT AS CENTERFOLD: FETISHISM IN MARY ELIZABETH BRADDON'SLADY AUDLEY'S SECRET
Authors: Felber Lynette
Published: July 2007

FROM “MY LAST DUCHESS”toThe Picture of Dorian Gray, portraits are ubiquitous in Victorian literature – lurking behind velvet curtains or stowed in locked attics, their canvases turned to the wall. The literary portrait, a variation on the copious nineteenth-century description typical of the Victorian novel, provides a verbal representation of physical appearance that most conspicuously functions to establish character. Literary portraits work vicariously, asking readers to conceptualize imaginatively what the characters actually see, requiring that they visualize a painting – see it in their mind's eye. Verbal and visual, private and portable, the literary portrait is a memento of an exciting reading experience. To better understand the appeal of literary portraits in the Victorian era, we might explore the effects of verbal description and the psychosexual impulses motivating the production of literary portraits. Victorian literary portraits commonly fetishize female subjects for a purportedly male gaze; even post-Freud, psychoanalysts view fetishism as a primarily masculine proclivity (Metz 89). Novels such as Mary Elizabeth Braddon'sLady Audley's Secret(1862), to name only one among many, present a fetishistic portrait that seems to be a classic illustration of Mulvey's observation that “[i]n a world ordered by sexual imbalance, pleasure in looking has been split between active/male and passive/female” (11). Film theory offers literary critics ways to theorize specularization – the behavior of “looking” – that precinematic viewers could not yet articulate.
GERTRUDE JEKYLL AND THE LATE-VICTORIAN GARDEN BOOK: REPRESENTING NATURE-CULTURE RELATIONS
Authors: Kehler Grace
Published: July 2007

THE VICTORIAN GARDEN BOOK ATTAINEDits peak popularity and status with the publications of Gertrude Jekyll, who, beginning in 1899, brought forth a total of fourteen books. Like those of her Victorian predecessors, Jekyll's garden books raise a series of questions about what it means to represent nature, for they expose a conflict: that between the human desire to forge a respectful connection with nature as an equal and the desire to exercise control over it. On the one hand, Victorian garden books, including Jekyll's, sought to encourage human knowledge of and interaction with the natural world. They built on the popularity of eighteenth-century botanical studies by disseminating detailed information about plants and their ecological habitats, frequently expressing wonder at nature's manifold and seemingly limitless creativity (Gates 36; Shteir 64–68). These admiring representations of nature cumulatively suggest a complex understanding of matter as dynamic and even purposeful, and the accompanying Victorian promotion of gardening as a hands-on, salutary activity for all classes at least tacitly positioned human development as inherently physical (Longstaffe-Gowan 151). On the other hand, gardening books not only attempted to aestheticize and manage nature, exerting rhetorical and visual control over physically powerful forces, but they also helped to consolidate nature's status as a commodity in Western culture as a site designed to regenerate, sooth, instruct, or sustain humans. From a twenty-first century point of view, the garden book constitutes an acute nature-culture problem because it so obviously relates to the issue of authority, specifically that of the individual writer whose public voice derives from her demonstrated ability to tend and to interpret the physical world. As ecocritics and postcolonial scholars justly charge, nature too often gets reduced to passive matter that is both available for and amenable to human cultivation and advancement. The garden book seemingly promotes such assumptions through its emphasis on the pleasures attendant on careful management of nature and through its idealized presentation of the gardener as an exemplar of self-disciplined creativity.
SPLIT ENDS? LITERATURE AND POLITICS AT THEFIN DE SIECLE
Authors: Macleod Jock
Published: July 2007

AS AN UNDERGRADUATE IN THE1970s, my introduction to the 1890s was perfunctory. Squeezed into a couple of weeks in the middle of a year-long course on “Victorian and Modern Literature,” the literature of the decade was reduced to aestheticism and decadence and presented as something of a preliminary to the real business of modernism. Such a focus reflected the scholarship of the time, in which thefin de sièclewas constructed as a moment of transition, one in which the political and socio-ethical dimensions so central to high Victorian literature were evacuated, as arguments for the autonomy of art came to dominate the literary cultural landscape. The organising principle was one of bifurcation: the separating out ofavant gardefrom bourgeois culture, the high from the low and, of particular relevance to this essay, literature from politics.
Atomic Force Spectroscopy on Poly(o-ethoxyaniline) Nanostructured Films: Sensing Nonspecific Interactions
Authors: Leite F.L. , Borato C.E. , da Silva W.T.L. , Herrmann P.S.P. , Oliveira O.N. , Mattoso L.H.C.
Published: July 2007

Atomic force spectroscopy (AFS) was used to measure interaction forces between the tip and nanostructured layers of poly(o-ethoxyaniline) (POEA) in pure water and CuSO4solutions. When the tip approach and retraction were carried out at low speeds, POEA chains could be physisorbed onto the Si3N4tip via nonspecific interactions. We conjecture that while detaching, POEA chains were stretched and the estimated chain lengths were consistent with the expected values from the measured POEA molecular weight. The effects from POEA doping could be investigated directly by performing AFS measurements in a liquid cell, with the POEA film exposed to liquids of distinct pH values. For pH ≥ 6.0, the force curves normally displayed an attractive region for POEA, but at lower pH values—where POEA is protonated—the repulsive double-layer forces dominated. Measurements in the liquid cell could be further exploited to investigate how the film morphology and the force curve are affected when impurities are deliberately introduced in the liquid. The shape of the force curves and the film morphology depended on the concentration of heavy metal in the liquid cell. AFS may therefore be used to study the interaction between film and analyte, with important implications for the understanding of mechanisms governing the sensing ability of taste sensors.
Mechanism of short-term ERK activation by electromagnetic fields at mobile phone frequencies
Authors: Friedman Joseph , Kraus Sarah , Hauptman Yirmi , Schiff Yoni , Seger Rony
Published: July 2007

The exposure to non-thermal microwave electromagnetic fields generated by mobile phones affects the expression of many proteins. This effect on transcription and protein stability can be mediated by the MAPK (mitogen-activated protein kinase) cascades, which serve as central signalling pathways and govern essentially all stimulated cellular processes. Indeed, long-term exposure of cells to mobile phone irradiation results in the activation of p38 as well as the ERK (extracellular-signal-regulated kinase) MAPKs. In the present study, we have studied the immediate effect of irradiation on the MAPK cascades, and found that ERKs, but not stress-related MAPKs, are rapidly activated in response to various frequencies and intensities. Using signalling inhibitors, we delineated the mechanism that is involved in this activation. We found that the first step is mediated in the plasma membrane by NADH oxidase, which rapidly generates ROS (reactive oxygen species). These ROS then directly stimulate MMPs (matrix metalloproteinases) and allow them to cleave and release Hb-EGF [heparin-binding EGF (epidermal growth factor)]. This secreted factor activates the EGF receptor, which in turn further activates the ERK cascade. Thus this study demonstrates for the first time a detailed molecular mechanism by which electromagnetic irradiation from mobile phones induces the activation of the ERK cascade and thereby induces transcription and other cellular processes.
Crucial roles of binding sites for NF-κB and C/EBPs in IκB-ζ-mediated transcriptional activation
Authors: Matsuo Susumu , Yamazaki Soh , Takeshige Koichiro , Muta Tatsushi
Published: July 2007

IκB-ζ [inhibitor of NF-κB (nuclear factor κB) ζ] is a nuclear protein that is induced upon stimulation of TLRs (Toll-like receptors) and IL (interleukin)-1 receptor. IκB-ζ harbours C-terminal ankyrin repeats that interact with NF-κB. Our recent studies have shown that, upon stimulation, IκB-ζ is essential for the induction of a subset of inflammatory genes, represented by IL-6, whereas it inhibits the expression of TNF (tumour necrosis factor)-α. In the present study, we investigated mechanisms that determine the different functions of IκB-ζ. We found that co-expression of IκB-ζ and the NF-κB subunits synergistically activates transcription of the hBD-2 (human β-defensin 2) and NGAL (neutrophil gelatinase-associated lipocalin) genes, whereas it inhibits transcription of E-selectin. Reporter analyses indicated that, in addition to an NF-κB-binding site, a flanking C/EBP (CCAAT/enhancer-binding protein)-binding site in the promoters is essential for the IκB-ζ-mediated transcriptional activation. Using an artificial promoter consisting of the NF-κB- and C/EBP-binding sites, transcriptional activation was observed upon co-transfection with IκB-ζ and NF-κB, indicating that these sequences are minimal elements that confer the IκB-ζ-mediated transcriptional activation. Chromatin immunoprecipitation assays and knockdown experiments showed that both IκB-ζ and the NF-κB subunits were recruited to the NGAL promoter and were essential for the transcriptional activation of the hBD-2 and NGAL promoters on stimulation with IL-1β. The activation of the NGAL promoter by transfection of IκB-ζ and NF-κB was suppressed in C/EBPβ-depleted cells. Thus IκB-ζ acts as an essential transcriptional activator by forming a complex with NF-κB on promoters harbouring the NF-κB- and C/EBP-binding sites, upon stimulation of TLRs or IL-1 receptor.
Age-associated perturbations in glutathione synthesis in mouse liver
Authors: Toroser Dikran , Sohal Rajindar S.
Published: July 2007

The nature of the mechanisms underlying the age-related decline in glutathione (GSH) synthetic capacity is at present unclear. Steady-state kinetic parameters of mouse liver GCL (glutamate–cysteine ligase), the rate-limiting enzyme in GSH synthesis, and levels of hepatic GSH synthesis precursors from the trans-sulfuration pathway, such as homocysteine, cystathionine and cysteine, were compared between young and old C57BL/6 mice (6- and 24-month-old respectively). There were no agerelated differences in GCL Vmax, but the apparent Km for its substrates, cysteine and glutamate, was higher in the old mice compared with the young mice (∼800 compared with ∼300 μM, and ∼710 compared with 450 μM, P<0.05 for cysteine and glutamate in young and old mice respectively). Amounts of cysteine, cystathionine and Cys-Gly increased with age by 91, 24 and 28% respectively. Glutathione (GSH) levels remained unchanged with age, whereas GSSG content showed an 84% increase, suggesting a significant pro-oxidizing shift in the 2GSH/GSSG ratio. The amount of the toxic trans-sulfuration/glutathione biosynthetic pathway intermediate, homocysteine, was 154% higher (P<0.005) in the liver of old mice compared with young mice. The conversion of homocysteine into cystathionine, a rate-limiting step in trans-sulfuration catalysed by cystathionine β-synthase, was comparatively less efficient in the old mice, as indicated by cystathionine/homocysteine ratios. Incubation of tissue homogenates with physiological concentrations of homocysteine caused an up to 4.4-fold increase in the apparent Km of GCL for its glutamate substrate, but had no effect on Vmax. The results suggest that perturbation of the catalytic efficiency of GCL and accumulation of homocysteine from the trans-sulfuration pathway may adversely affect de novo GSH synthesis during aging.
The iron-responsive element (IRE)/iron-regulatory protein 1 (IRP1)–cytosolic aconitase iron-regulatory switch does not operate in plants
Authors: Arnaud Nicolas , Ravet Karl , Borlotti Andrea , Touraine Brigitte , Boucherez Jossia , Fizames Cécile , Briat Jean-François , Cellier Françoise , Gaymard Frédéric
Published: July 2007

Animal cytosolic ACO (aconitase) and bacteria ACO are able to switch to RNA-binding proteins [IRPs (iron-regulatory proteins)], thereby playing a key role in the regulation of iron homoeostasis. In the model plant Arabidopsis thaliana, we have identified three IRP1 homologues, named ACO1–3. To determine whether or not they may encode functional IRP proteins and regulate iron homoeostasis in plants, we have isolated loss-of-function mutants in the three genes. The aco1-1 and aco3-1 mutants show a clear decrease in cytosolic ACO activity. However, none of the mutants is affected in respect of the accumulation of the ferritin transcript or protein in response to iron excess. cis-acting elements potentially able to bind to the IRP have been searched for in silico in the Arabidopsis genome. They appear to be very rare sequences, found in the 5′-UTR (5′-untranslated region) or 3′-UTR of a few genes unrelated to iron metabolism. They are therefore unlikely to play a functional role in the regulation of iron homoeostasis. Taken together, our results demonstrate that, in plants, the cytosolic ACO is not converted into an IRP and does not regulate iron homoeostasis. In contrast with animals, the RNA binding activity of plant ACO, if any, would be more likely to be attributable to a structural element, rather than to a canonical sequence.
Rhizavidin from Rhizobium etli: the first natural dimer in the avidin protein family
Authors: Helppolainen Satu H. , Nurminen Kirsi P. , Määttä Juha A. E. , Halling Katrin K. , Slotte J. Peter , Huhtala Tuulia , Liimatainen Timo , Ylä-Herttuala Seppo , Airenne Kari J. , Närvänen Ale , Jänis Janne , Vainiotalo Pirjo , Valjakka Jarkko , Kulomaa Markku S. , Nordlund Henri R.
Published: July 2007

Rhizobium etli CFN42 is a symbiotic nitrogen-fixing bacterium of the common bean Phaseolus vulgaris. The symbiotic plasmid p42d of R. etli comprises a gene encoding a putative (strept)avidin-like protein, named rhizavidin. The amino acid sequence identity of rhizavidin in relation to other known avidin-like proteins is 20–30%. The amino acid residues involved in the (strept)avidin–biotin interaction are well conserved in rhizavidin. The structural and functional properties of rhizavidin were carefully studied, and we found that rhizavidin shares characteristics with bradavidin, streptavidin and avidin. However, we found that it is the first naturally occurring dimeric protein in the avidin protein family, in contrast with tetrameric (strept)avidin and bradavidin. Moreover, it possesses a proline residue after a flexible loop (GGSG) in a position close to Trp-110 in avidin, which is an important biotin-binding residue. [3H]Biotin dissociation and ITC (isothermal titration calorimetry) experiments showed dimeric rhizavidin to be a high-affinity biotin-binding protein. Its thermal stability was lower than that of avidin; although similar to streptavidin, it was insensitive to proteinase K. The immunological cross-reactivity of rhizavidin was tested with human serum samples obtained from cancer patients exposed to (strept)avidin. No significant cross-reactivity was observed. The biodistribution of the protein was studied by SPECT (single-photon emission computed tomography) imaging in rats. Similarly to avidin, rhizavidin was observed to accumulate rapidly, mainly in the liver. Evidently, rhizavidin could be used as a complement to (strept)avidin in (strept)avidin–biotin technology.
Biosynthesis and metabolism of leukotrienes
Authors: Murphy Robert C. , Gijón Miguel A.
Published: July 2007

Leukotrienes are metabolites of arachidonic acid derived from the action of 5-LO (5-lipoxygenase). The immediate product of 5-LO is LTA4 (leukotriene A4), which is enzymatically converted into either LTB4 (leukotriene B4) by LTA4 hydrolase or LTC4 (leukotriene C4) by LTC4 synthase. The regulation of leukotriene production occurs at various levels, including expression of 5-LO, translocation of 5-LO to the perinuclear region and phosphorylation to either enhance or inhibit the activity of 5-LO. Several other proteins, including cPLA2α (cytosolic phospholipase A2α) and FLAP (5-LO-activating protein) also assemble at the perinuclear region before production of LTA4. LTC4 synthase is an integral membrane protein that is present at the nuclear envelope; however, LTA4 hydrolase remains cytosolic. Biologically active LTB4 is metabolized by ω-oxidation carried out by specific cytochrome P450s (CYP4F) followed by β-oxidation from the ω-carboxy position and after CoA ester formation. Other specific pathways of leukotriene metabolism include the 12-hydroxydehydrogenase/15-oxo-prostaglandin-13-reductase that forms a series of conjugated diene metabolites that have been observed to be excreted into human urine. Metabolism of LTC4 occurs by sequential peptide cleavage reactions involving a γ-glutamyl transpeptidase that forms LTD4 (leukotriene D4) and a membrane-bound dipeptidase that converts LTD4 into LTE4 (leukotriene E4) before ω-oxidation. These metabolic transformations of the primary leukotrienes are critical for termination of their biological activity, and defects in expression of participating enzymes may be involved in specific genetic disease.
Arterial stiffness: clinical relevance, measurement and treatment
Authors: Hamilton Paul K. , Lockhart Christopher J. , Quinn Cathy E. , Mcveigh Gary E.
Published: July 2007

Most traditional cardiovascular risk factors alter the structure and/or function of arteries. An assessment of arterial wall integrity could therefore allow accurate prediction of cardiovascular risk in individuals. The term ‘arterial stiffness’ denotes alterations in the mechanical properties of arteries, and much effort has focused on how best to measure this. Pulse pressure, pulse wave velocity, pulse waveform analysis, localized assessment of blood vessel mechanics and other methods have all been used. We review the methodology underlying each of these measures, and present an evidence-based critique of their relative merits and limitations. An overview is also given of the drug therapies that may prove useful in the treatment of patients with altered arterial mechanics.
Prognosis and prediction of response in breast cancer: the current role of the main biological markers
Authors: Ravaioli A. , Bagli L. , Zucchini A. , Monti F.
Published: July 2007

Abstract. In the medical literature there are frequently conflicting reports on the utility of biological tumour markers available in the clinical management of breast cancer. In this review we analyse current information on the relationships between the most widely investigated breast cancer biological markers including oestrogen and progesterone receptors, p53, Bcl‐2, c‐erbB‐2, cyclin expression, proliferative activity, DNA ploidy and the urokinase plasminogen activation system, as well as their relevance to prognosis and response to clinical treatment. By biological prognostic indicator, we mean a marker that correlates with survival and disease‐free survival; the term predictor marker indicates a marker that is capable of predicting tumour sensitivity or resistance to various therapies. Similarly to other authors' experiences, our analysis suggests that oestrogen receptors are weak prognostic indicators and good predictors of response to endocrine therapy. Furthermore, there are consistent data suggesting that proliferation indices are good indicators of prognosis, and that they are directly related to response to chemotherapy and closely related to response to hormonotherapy. On the contrary, there is no evidence or conflicting data for all of the other biological markers. These should be considered in the context of randomized trials in order to precisely define their prognostic and predictive roles. p53 and c‐erbB‐2 seem to be the most promising factors, but their use in routine practice still needs validation.
Mitogen‐activated protein kinase signalling pathways triggered by the hepatitis C virus envelope protein E2: implications for the prevention of infection
Authors: Zhao L.‐J. , Zhao P. , Chen Q.‐L. , Ren H. , Pan W. , Qi Z.‐T.
Published: July 2007

Abstract.  Objective: Hepatitis C virus (HCV) is a major pathogenic factor of liver diseases. During HCV infection, interaction of the envelope protein E2 of the virion, with target cells, is a crucial process for viral penetration into the cell and its propagation. We speculate that such interaction may trigger early signalling events required for HCV infection. Materials and methods: Human liver cell line L‐02 was treated with HCV E2. The kinase phosphorylation levels of mitogen‐activated protein kinase (MAPK) signalling pathways in the treated cells were analyzed by Western blotting. The proliferation of the E2‐treated cells was evaluated by MTT assay. Results: HCV E2 was shown to be an efficient activator for MAPK pathways. Levels of phosphorylation of upstream kinases Raf‐1 and MEK1/2 were seen to be elevated following E2 treatment and similarly, phosphorylation levels of downstream kinases MAPK/ERK and p38 MAPK also increased in response to E2 treatment, and specificity of kinase activation by E2 was confirmed. E2‐induced MAPK/ERK activation was inhibited by the MEK1/2 inhibitor U0126 in a concentration‐dependent manner. Blockage of relevant cellular receptors reduced activation of Raf‐1, MEK1/2, MAPK/ERK and p38 MAPK by E2, indicating efflux of the E2 signal from extracellular to the intracellular spaces. Thus, kinase cascades of MAPK pathways were continuously affected by E2 presence. Moreover, enhancement of cell proliferation by E2 appeared to be associated with the dynamic phosphorylation of MAPK/ERK and p38 MAPK. Conclusion: These results suggest that MAPK signalling pathways triggered by E2 may be a potential target for prevention of HCV infection.
Two newly identified SipA domains (F1, F2) steer effector protein localization and contribute to Salmonella host cell manipulation
Authors: Schlumberger Markus C. , Käppeli Rina , Wetter Michael , Müller Andreas J. , Misselwitz Benjamin , Dilling Sabrina , Kremer Marcus , Hardt Wolf‐Dietrich
Published: July 2007

Salmonella Typhimurium causes bacterial enterocolitis. The type III secretion system (TTSS)‐1 is a key virulence determinant of S. Typhimurium mediating host cell invasion and acute enterocolitis. The TTSS‐1 effector protein SipA is transported into host cells, accumulates in characteristic foci at the bacteria–host cell interface, manipulates signalling and affects virulence. Two functional domains of SipA have previously been characterized: The N‐terminal SipA region (amino acids 1–105) mediates TTSS‐1 transport and the C‐terminal SipA ‘actin‐binding’ domain (ABD; amino acids 446–685) manipulates F‐actin assembly. Little is known about the central region of SipA. In a deletion analysis we found that the central SipA region harbours two distinct functional domains, F1 and F2. They are involved in SipA focus formation and host manipulation. The F1 domain (amino acids 170–271) drives SipA focus formation and domain F2 (amino acids 280–394) enhances this process by mediating SipA–SipA interactions. SipA variants lacking the F1‐, the F2‐ or the actin binding domain were attenuated in virulence assays, namely host cell invasion and/or virulence in a mouse model for enterocolitis. Our results show that the newly identified SipA domains have distinct functions. Nevertheless, cooperation between the SipA domains F1, F2 and ABD is required to promote Salmonella virulence.