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The purpose of this paper is to provide a solution for Reynolds equation with both throttling term and reverse throttling term and provides a reference for changing damping of hydrostatic bearing.

The reverse throttling term is introduced into the Reynolds equation, and the adaptive damping factor is used in the Newton iteration method to improve convergence of numerical calculations. The static and dynamic performances of this bearing are numerically investigated by the finite-element method.

The results indicate that the reflux orifices lead to a decrease in load capacity at a high eccentricity ratio. Additionally, the mass inflow rate is increased; however, the additional inflow increase can be controlled by enhanced backpressure of the reflux orifice. Nevertheless, the bearing with the reflux orifice shows superiority in resisting high-frequency disturbances and enhances direct damping by 20% under a high backpressure.

This work presents an adaptive Newton damping iterative method for solving Reynolds equation with both throttling term and reverse throttling term. This work also provides a new idea for bearing structure design in improving damping.

This paper aims to provide an insight into recent advancements and developments of robotics for Natural Orifice Transluminal Surgery (NOTES) procedures.

Following an introduction that highlights the evolution from Minimally Invasive Surgery (MIS) to NOTES in the medical field, this paper reviews the main robotics systems that have been designed and implemented for MIS and NOTES, summarising their advantages and limitations and remarking the technological challenges and the requirements that still should be addressed and fulfilled.

The state-of-the-art presented in this paper shows that the majority of the platforms created for NOTES are laboratory prototypes, and their performances are still far from being optimal. New solutions are required to solve the problems confronted by the proposed systems such as the limited number of DOFs, the limited resolution, the optimal fixation and stiffening of the instruments for enabling stable and precise operation, the effective transmission of forces to the tip tools, the improvement of the force feedback feeling and the proper visualization and spatial orientation of the surgical field. Advances in robotics can contribute significantly to the development and future implementation of the NOTES procedure.

This paper highlights the current trends and challenges ahead in robotics applied to NOTES procedure.

Corrosion in one or more of its various forms is attendant in almost every stage of operation in the petroleum and petrochemical industries and is recognised as a major cost item. There is general recognition in these industries of the vast savings that can be made by the judicious selection of materials to combat corrosion, and considerable effort is expended in the evaluation of materials of construction likely to provide economic solutions to many corrosion problems.

The first part of this article dealing with Degrees of Vacuum, Pump Design, Use of Cold Traps, etc., appeared in our October issue.

A large number of resins and polymers are used as film formers. These have been undergoing modifications to meet the growing demand. One of the modifications involves chlorination and products like chlorinated rubber, chlorinated biphenyls, chlorinated paraffins, chlorinated poly(vinyl chloride), chlorinated polyethylene, chlorinated polypropylene and chlorinated polyether are the result. Besides these well‐established chlorinated products, chlorinated drying and semi‐drying alkyds, chlorinated epoxy esters and chlorinated acrylic polymers have also been studied.

Globalization, advanced by technologies of production and information, created seamless world markets with profound impacts on the world economy. Vast amounts of wealth have been created, but that wealth has been unequally distributed. Such inequality has meant that large numbers of young people have not been able to find the kinds of jobs and careers that provide the “goods” life extolled in a consumer society. Nor do the dominant values of rationality, neo-liberalism or secularism hold much appeal. These conditions have encouraged the emergence of a number of subcultures of transgression, identity-granting communities of meaning which provide members with a sense of community with recognition and empowerment. As many such subcultures repudiate dominant norms, we note how they resemble the medieval carnival, which Bakhtin showed was a time and place of inversion, transgression, and celebration of the grotesque. It allowed the common people encapsulate realms of agency to articulate disdain and resistance. Yet this served to reproduce the dominant system.

In much the same way, insofar as globalization is intimately tied to cities, we have seen the growing importance of cities as nodal points for global commerce as well as sites for entertainment and tourism. These factors, together with the longstanding anonymity and toleration of the city, have become focal points for the emergence of a number of oppositional subcultures. They include those who embrace extreme body modification, numerous forms of body adornment through piercings (rings, posts, studs), tattoos, and surgical modifications such as implanted horns, furrows, or split tongues. Following Simmel, adornment can be seen as a means of inclusion within a group and differentiation from others. The practitioners of extreme body modification label themselves “urban primitives,” who see themselves rejecting global modernity, the occupation-based status hierarchies of the dominant occupational system and its shallow, materialistic culture. They see themselves as a moment of the “transvaluation of values” in which Dionysian passion triumphs over Apollonian control and restraint. This is especially evident in various genital decorations in which what heretofore has been private and exposure was a matter of shame. There has been a “cultural transformation of the pubic sphere.” While such groups find community, identity and recognition, they must also be understood as a key ingredient of the city in a global age in which diversity, cosmopolitanism, and the offbeat constitute essential moments of urban ambience.

The purpose of this paper is to present a rationale for increasing initiatives for early intervention of emotional and behaviour difficulties.

The authors draw on existing literature regarding rates of emotional and behavioural difficulties together with risk factors and processes related to the development of such difficulties.

Rates of emotional and behavioural difficulties amongst children with learning and developmental difficulties are high. A combination of factors relating to the child, the family system, and wider social contexts is likely to account for this.

Increased attempts to provide early intervention to children with learning and developmental disabilities together with their families are warranted. Recommendations are made regarding how the development of such supports might best be taken forward.

Whilst drawing on pre-existing literature, the value of this paper is the way in which this has been drawn together to provide an overview of risk and development of behavioural and other difficulties amongst children with learning/developmental disabilities.

To prevent the formation of ice on aircraft, the air‐stream for cooling the engine enters through a diverging inlet and after becoming heated by the engine, which may be of either air‐cooled or liquid‐cooled type, passes along conduits, at the leading edges of the wings or at other parts, and leaves by converging outlets. The kinetic energy of the stream is thus first converted into pressure energy and then reconverted to kinetic energy, the air heated by the engine or radiator being taken from a point at low pressure and velocity. Air enters at diverging inlets 13 above the two engines, and after passing over the radiators 11 passes by converging conduits 14, 15 to outlets 17, IS. In Fig. 4 (not shown), the aircraft has a single engine in the nose with a single radiator below it, and in Fig. 6 (not shown) a single engine has two radiators. The engine oil‐cooler, if provided, may also be situated in the passage.

In October, 1902, the Secretary of the Mineral Water Bottle Exchange and Trade Protection Society addressed a letter to the Clerk of the London County Council stating that aerated and mineral waters are, in many instances, manufactured under insanitary conditions, and suggesting that the Council should take action in the matter. The Public Health Committee of the Council thereupon directed that a number of premises where aerated waters are manufactured should be inspected, and, in February, 1903, Dr. Shirley Murphy, the Medical Officer to the Council, presented a report drawn up by Dr. Hamer, the Assistant Medical Officer, by whom the inspections ordered were carried out. Dr. Hamer came to the conclusion that it was most desirable in the interests of the consumer that the manufacture of aerated waters in London should be regulated and controlled. The quantity of aerated water sold in London is very large, and Dr. Hamer's inspection of numerous premises showed that there are many possible sources of dangerous contamination of the water used during the process of the manufacture. We are in a position to state that Dr. Hamer was thoroughly justified in drawing the conclusions which appear in his report. The enormous growth in popularity during recent years of aerated and mineral waters, while unquestionably fraught with a most important influence for good, has brought a number of firms into existence who manufacture more or less inferior and, in some instances, positively injurious and dangerous waters, and who place their products on the market at “cutting” prices, with the result that the honest and careful manufacturer on the one hand, and the public on the other, are made to suffer. Unfair “competition” of the kind referred to exists, of course, in every trade, and only by the authoritative approval of the good and, by implication, the authoritative condemnation of the bad, can such “competition” be effectively checked. But where the health of the consumer is directly threatened or affected, as it particularly is by the supply of inferior or actually injurious aerated waters, the necessity for adequate regulation and control is immediately obvious. The matter cannot be dealt with under the Sale of Food and Drugs Acts. It is not one involving analysis only but, so far as analysis is concerned, the provisions of the Acts make it impossible to carry out the analytical investigations that would be required. In addition to the official registration of all manufacturers of mineral and aerated waters, a combination of inspection and analysis by an authoritative bedy of some kind, or by a recognised individual authority, is necessary to supply a sufficient guarantee to the public and efficient protection to the manufacturer and vendor of pure and high‐class waters.

The purpose of this study is to prepare new pigments derived from Red Lake C (RLC) to be applied in the inks industry and to identify their chemical nature, as well as their physical properties.

A number of pigments that could be applied in special printing were prepared via the reactions of RLC with appropriate Ni(II) and Zn(II) salts in aqueous and ethanolic solutions. The obtained pigments were prepared as solid compounds and characterized using different instrumental analysis such as Ultraviolet-Visible, Fourier Transform Infrared Spectroscopy, ¹H NMR spectra and magnetic measurements. The physical properties of these pigments were investigated using “American Standard Testing Methods” (ASTM). After that, the pigments were applied in ink formulations to test their performance and open the way to their real applications in the printing inks industry.

The results of this work revealed that the performance of the new prepared pigments is closer to the performance of the commercial pigments which are already used in ink industry.

Red lake C, as well as the new pigments, can be applied in other different industries such as coated papers, crayons, rubber and baking enamels.

The prepared pigments will be economically feasible and a good alternative to the original expensive commercial pigments which are already used in the inks industry.