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This study aims to test the reliability of ultrasound to graduate synovitis in static and video images, evaluating separately grayscale and power Doppler (PD), and combined. Thirteen trained rheumatologist ultrasonographers participated in two separate rounds reading 42 images, 15 static and 27 videos, of the 7-joint count [wrist, 2nd and 3rd metacarpophalangeal (MCP), 2nd and 3rd interphalangeal (IPP), 2nd and 5th metatarsophalangeal (MTP) joints]. The images were from six patients with rheumatoid arthritis, performed by one ultrasonographer. Synovitis definition was according to OMERACT. Scoring system in grayscale, PD separately, and combined (GLOESS-Global OMERACT-EULAR Score System) were reviewed before exercise. Reliability intra- and inter-reading was calculated with Cohen's kappa weighted, according to Landis and Koch. Kappa values for inter-reading were good to excellent. The minor kappa was for GLOESS in static images, and the highest was for the same scoring in videos (k 0.59 and 0.85, respectively). Excellent values were obtained for static PD in 5th MTP joint and for PD video in 2nd MTP joint. Results for GLOESS in general were good to moderate. Poor agreement was observed in 3rd MCP and 3rd IPP in all kinds of images. Intra-reading agreement were greater in grayscale and GLOESS in static images than in videos (k 0.86 vs. 0.77 and k 0.86 vs. 0.71, respectively), but PD was greater in videos than in static images (k 1.0 vs. 0.79). The reliability of the synovitis scoring through static images and videos is in general good to moderate when using grayscale and PD separately or combined.

The filtered tailings technology consists in reducing the water content of tailings ahead of their final disposal and later storing them in stacks with no containment structures. Since the stability of the waste storage facility (WSF) partly relies on the increase of strength due to suction, the unsaturated condition should be always preserved. Therefore, limiting the water content by the time of burying the tailings under the next lifts of the stack and preventing the infiltration of rainfall water into the already buried tailings becomes essential. This paper presents two field column tests performed with the Casposo Mine tailings material. The initial desiccation process and the effects of a number of rainfall events at the actual mine site conditions were observed during a period of 14 months. The columns were 1 m high and the water content was monitored at five different depths. In one of the columns, a gravel layer made of crushed waste rock was intercalated between tailings layers, simulating the layered structure of the actual WSF. In this case, capillary barrier effect developed at the tailings layer-waste rock interphase. This effect is availed in the WSF design for preventing the infiltration of rain water into the lower layers, keeping it close to the deposit top surface for ease of evaporation and preserving the unsaturated condition of the deposit. The water storage capacity of the top tailings layer is evaluated, both analytically and experimentally, in order to study how likely would be the infiltration of water into the deep layers of the deposit.

In the context of research into deep nuclear waste disposal, various works have concerned the hydromechanical behavior of Boom clay, a stiff plastic clay extracted in the SCK-CEN Underground Research Laboratory near the Mol City (Belgium), at a depth of 223 m. Due to some amount of smectite minerals in the clay fraction, Boom clay exhibits swelling properties when hydrated under low stresses. To investigate some aspects of the hydromechanical behavior of Boom clay, oedometer compression tests were carried out on samples of Boom clay close to saturation and submitted to an initial suction. During oedometer compression, the changes in suction with increased vertical stress are monitored by means of a high capacity tensiometer installed at the bottom of the sample. Some aspects related to hydromechanical couplings are examined through the investigation of the changes in suction during oedometer compression, a somewhat delicate and poorly documented experimental approach. A comparison is also made with a completely different soil sample under suction, i.e. a statically compacted unsaturated low plasticity silt. Some technical difficulties typical of this new experimental approach are first described in detail so as to optimize the interpretation of the data obtained. The experiment allows the determination of the point at which suction is changed to positive pressure during compression. Below this point, the ratio between the vertical stress and the change in suction are determined. Above this point, the data show that positive pore pressures are dissipated in a common way. The suction/stress behavior during unloading is also described and discussed. Finally, an interpretation in terms of microstructure effects is provided for both samples. The experimental approach initiated here seems to provide interesting further application to better understand hydromechanical couplings in natural soils in relation with suction increase during stress release.

This paper studies the structure of order-isomorphisms between the cones of strictly-positive-valued elements of subspaces of two spaces of continuous functions; a complete description is obtained in some cases. Conditions are also found that ensure that such an order-isomorphism is linear provided it is homogeneous along at least one ray.

A genuine faceless cone is a non-empty linear cone that is open in some linear topology and includes no line. This paper describes all assignments of metrics to genuine faceless cones such that every linear mapping between cones is a contraction.

We consider a homogeneous linear differential equation with delays u.+Mu=0,where u takes values in a Banach space and M is a memory with bounded recall under natural Caratheodory conditions, i.e., a linear mapping from the continuous to the locally Bochner-integrable functions such that Mu on [a, b] depends only on u on [a−l, b] for a suitable recall bound l, and M satisfies a reasonable boundedness condition. The presence of the conditional exponential stability behaviour called an exponential dichotomy—which is known to be related to the existence of bounded solutions of the inhomogeneous equation for right-hand sides in a suitable function space — is examined when the equation is periodic; it is shown to be equivalent to a splitting of the spectrum of the transition operators corresponding to a period. More detailed results are obtained when the equation is autonomous.

James [4] introduced the concept of a uniformly non-square unit ball and certain other geometric properties of Banach spaces, all related to reflexivity. The purpose of this paper is to focus attention on a similar property, a generalized (negation ot) uniform non-squareness, and show that it can be expressed in terms of the "girth" of the unit ball, as introduced by Sch~iffer [5], i.e., the infimum of the lengths of centrally symmetric simple closed rectifiable curves in its boundary. Specifically, it is shown that a Banach space is reflexive if the girth of its unit ball is not 4.

It is proved that every centrally symmetric simple closed curve on the boundary of a centrally symmetric convex body in a three-dimensional linear space possesses an inscribed concentric affinely regular hexagon. This result is used to settle affirmatively a conjecture in [2] about the metric structure of the unit spheres of three-dimensional normed space.

An increasing sequence of closed subsets of the unit interval is constructed, such that no set in the sequence is essentially covered by a finite union of translates of the set preceding it. The result is applied to construct a pathological right-translation-invariant ideal of the Banach latticeL ∞ onR +.

It is shown that any two points on the surface of the unit ball ofL 1(μ), where the measureμ is non-atomic, may be joined in the surface by a curve whose length is equal to the straight-line distance between its endpoints. This property is contrasted with the metric properties of the unit sphere in other L-spaces.

During the writing of the author's doctoral dissertation on almost periodic differential equations, he received valuable suggestions from ProfessorB. L. van der Waerden concerning the theory of stability of linear equations; these suggestions became an important germ of the author's contribution to the series of papers to which this is the latest addition. It is but fitting that, the wheel having come full circle, this chapter on almost periodic equations should be dedicated

The analogy between differential equations and difference equations has been recognized and exploited very frequently. Thus, shortly after the publication of PERRON'S paper on stability [5], there appeared a corresponding paper by TALI [3], a student of PERRON'S, with an almost identical title, in which similar methods were used to obtain analogous results for difference equations. In both papers a central concern is the relationship, for linear equations, between the condition that the non-homogeneous equation have some bounded solution for every bounded "second member" on the one hand, and a certain form of behaviour of the solutions of the homogeneous equation on the other. PERRON'S results for linear differential equations are the starting point of extensive later developments; some recent ones are found in a series of papers by MASSERA and SCH~FFER, later continued by SCH~,FFER, and brought together in a monograph [4] (see also [1], Chs. 12 and 13). The purpose of the present paper is to provide for linear difference equations the analogues of the most central results for linear differential equations in that theory.