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International audience; This paper provides compact vector and matrix forms of the nonlinear dynamics of class-1 and class-k tensegrity systems with fluid forces incorporated. Firstly, the equation of motion (both translation and rotation) of a single rod is modeled. Then, the fluid forces by fluid particles interacting with the rod are modeled and added to the derived dynamic equations of the rod. Then, by stacking all the governing equations of motion for each rod, compact vector and matrix forms of class-1 and class-k tensegrity dynamics are formulated. Finally, three examples based on a three-dimensional prism model with and without considering fluid forces, with and without fluid inlet velocity, and landing to the ground with and without fluid influence are simulated and compared. Results show that the simulations match well with physics. The fluid provides significant damping to the dynamics of the structure. This work enables the ability to do fluid-structure interaction studies of any tensegrity structures. The principles developed here can also be used for analyzing various kinds of tensegrity structures operating in the air or underwater.

In recent years, the use of large diameter reverse osmosis (RO) elements has gained some considerable momentum as a potential means of lowering the overall cost of desalination by membrane treatment. By the beginning of 2008, a number of systems have been installed so operating experience exists. Along with some design issues, this paper will review some of the currently operating installations and discuss why large diameter elements were selected for specific projects. The commercial availability of large diameter elements also offers opportunities for alternative system and building layouts. These considerations have implications for cost and space savings. This paper will also review the design approach for large volume systems using the large diameter elements, looking at factors such as the array and rack designs, plant layout and pump sizing.

This paper argues that although there has been an increasing use of the term 'empowerment' in the nursing literature, the word is sometimes employed uncritically and in inappropriate contexts. The origins of the expression in community development work are noted, in an effort to set the activity of empowerment in its political context and to discuss the implications of this for the relative power of health professionals and service users. A distinction is drawn between the meaning of the term at the individual and the community level and an outline strategy is discussed for nurses who may wish to think through what empowering patients or clients will entail.

Rather than the traditional vector differential equation, this paper introduces rigid body dynamics in a new form, as a matrix differential equation. For a system of nb rigid bodies, the forces are characterized in terms of network theory, and the kinematics are characterized in terms of a directed graph of the connections of all members. The dynamics are characterized by a second order differential equation in a 3 × 2nb configuration matrix. The first contribution of the paper is the dynamic model of a broad class of systems of rigid bodies, characterized in a compact form, requiring no inversion of a variable mass matrix. The second contribution is the derivation of all equilibria as linear in the control variable. The third contribution is the derivation of a linear model of the system of rigid bodies. One significance of these equations is the exact characterization of the statics and dynamics of all class 1 tensegrity structures, where rigid bar lengths are constant and the string force densities are control variables. The form of the equations allow much easier integration of structure and control design since the control variables appear linearly. This is a significant help to the control design tasks.

It is argued that the prevalence of AIDS is substantially under-represented in existing national AIDS data. Thus although official statistics demonstrate significant recent shifts in transmission routes for HIV, health educators are faced with a problem because it is difficult to develop preventive strategies against a syndrome whose prevalence can only be estimated. Problems of the true extent of the prevalence of HIV are compounded when there is a lack of knowledge about the specifics of heterosexual behaviour. It is unwise to assume that the protective strategies developed by gay men in the face of HIV are routinely available for adoption by heterosexuals, who are characterised by social divisions of age, gender and relative amounts of social power. These concerns represent a problem for health educators. To date, sociological work may not have made the most effective contribution in its support of intervention strategies against HIV/AIDS. Examination of the empirical literature on lay concepts of health and illness reveals a pessimistic stance on the part of some researchers about the ability of individuals to modify behaviour. More positive readings of their own data are possible. The traditional concerns to emphasise the socio-economic determinants of health and behaviour, now also shared by some health educators, should not obscure a concern for the fate of individuals. The most effective contribution that health promotion may be able to make to the control of HIV in the heterosexual population is to assist in the development of strategies of empowerment and ‘horizontal intervention’.

This section concerns raw jade finds in Europe and their uses, both ancient and modern. The main sites are listed below. Geological reports over the past few decades have included notices of small finds in situ in France, Germany and Finland but they are negligible in both quality and quantity. Many other pieces of both nephrite and jadeite, as rough stones and as finished objects, have been found all over Europe but the areas mentioned here are those where only verified local finds have been made. Others found may be of random occurrence as a result of natural causes such as the movement of glaciers or of human migrations.

Although the countries of the Islamic Near East v; inherited the technology for working hardstones J S from the ancient empires of Western Asia such as Sassanian Iran and Byzantium, it was not until the early 15th century that we find these skills being consistently applied to the working of nephrite jade.1 Prior to this, the most spectacular Islamic hardstone objects were the superb rock crystal vessels produced for the Fatimid rulers of Egypt during the 10th and 11th centuries ad.2 Less ambitious, but far more prolific than these rarities were the amulets and personal seals made from various hardstones and used throughout the lands of Islam down to the present time.3 This widespread tradition of seal engraving ensured that the technical means of working materials of similar hardness to jade was readily available throughout the region. Therefore it remained only for Muslim hard-stone workers (hakkak) to gain access to adequate supplies of nephrite for the art of jade-carving to develop.

The recent commercialization of cross flow microfiltration in the food industry includes such applications as; the clarification of highly colored fruit juices (grape, cranberry, cherry, etc.); the clarification of gelatin prior to concentration by ultrafiltration; and the filtration of liquid sweeteners for the beverage industry. Cross flow filtration shows particularly attractive economics in the displacement of diatomaceous earth filtration as had already been proven in the 80’s, in the apple juice industry, worldwide. Higher and more consistent product clarity, lower operating costs, and ease of operation compared to rotary vacuum filtration, as well as elimination of the need to buy (frequently import) and subsequently dispose of used filtration aids (diatomaceous earth, etc.), have provided the incentive to switch to cross flow microfiltration.