Quick attach and release fluid coupling assembly is self-aligning, self-sealing

Fluid coupling assembly that is self-aligning, self-sealing and contains a bellow ball and socket coupling for quick attach and release is highly reliable and can handle cryogenic fluids where icing is encountered. The fluid coupling assembly is used in many fluid systems but is particularly applicable to cryogenic systems

Estimating Drift Parameters in a Fractional Ornstein Uhlenbeck Process with Periodic Mean

We construct a least squares estimator for the drift parameters of a fractional Ornstein Uhlenbeck process with periodic mean function and long range dependence. For this estimator we prove consistency and asymptotic normality. In contrast to the classical fractional Ornstein Uhlenbeck process without periodic mean function the rate of convergence is slower depending on the Hurst parameter $H$, namely $n^{1-H}$

A suite of mathematical models to simulate the water and salt circulation in the Vaal River water supply system

A thesis submitted to the Faculty of Engineering University of the Witwatersrand Johannesburg ' for the degree of Doctor of Philosophy September 1981The Pretoria-Witwatersrand-Vereeniging (PW) complex relies for water supply on the resources of the Vaal basin# supplemented by Importation from the Tugela river. Most of the water supplied to the region is abstracted from the Vaal Barrage# which is also the sink for much of the water-borne pollution generated in the southern portion of the PWV complex. This feature of the system has led to an ever-increasing build-up of total dissolved solids (TDS) in the water supplies# resulting in substantial economic loss to consumers. Increasing mineralization is ascribable mainly to return of effluents to the Vaal Barrage where the concentrated salts are re-introduced to the Rand Water Board distribution system. The problem is exacerbated by the washoff, during the wet season# of enormous diffuse-source salt loads# leading to intolerably high peak TDS concentrations. A suite of deterministic mathematical models has been developed, and successfully tested, with the aim of predicting the anticipated severity of mineralization problems of the future and of facilitating objective comparison of the merits of various ameliorative measures. The first of the suite is the daily washoff model, designed to simulate daily catchment runoffs and associated daily diffusesource salt washoff. Basic input is daily meteorological data. In the model account is taken of both surface and sub-surface flow processes. Calibration of the model parameters for each of the twelve sub-catchments comprising the southern PWV region was effected with records of discharge and water quality at key monitoring points. A relationship was established between industrial water consumption and diffuse-source salt generation rates by means of which pollution levels likely to arise in the future could be predicted. Daily fluctuations of discharge and salt concentration at any point in the tributaries of the southern PWV region and in the Vaal Barrage, as well as water and salt storages in the major impoundments of the Vaal basin are simulated by means of the daily feed-back model. A feed-back element is incorporated which accounts for the mixing of water distributed to each of 27 sub-regions of the southern PWV catchment, the addition of salts through usage and the routing of effluents, together with diffuse-source washoff generated by the first model, through the tributary system back into the Barrage. The transmission of pollutants through the Barrage is simulated by means of a one-dimensional, cell-type level-pool model. This model was used to check the reliability of calibrated parameter values used in the daily washoff model by comparing simulated daily salt concentrations in the Vaal Barrage with those observed at the Rand Water Board Barrage intakes. The third model, a simplified version of the daily feed-back model designed to operate at a monthly computational time step, was developed to facilitate preliminary comparisons of the various options. This coarse tlme-etep model is relatively cheaper to run and makes pos-lble the testing of each option with several different hydrological sequences. Economic factors relating salt concentration in water supply to costs to consumers have also been incorporated. The two feed-back models were designed in such a way that a wide variety of planning and management options could be modelled with the minimum of programming changes. Procedures for comparing, with the aid of the models, the merits of various planning and management options to improve water quality have been evolved and are illustrated by way of example

Clinical and functional characterisation of a novel TNFRSF1A c.605T > A/V173D cleavage site mutation associated with tumour necrosis factor receptor-associated periodic fever syndrome (TRAPS), cardiovascular complications and excellent response to etanercept treatment.

Objectives: To study the clinical outcome, treatment response, T-cell subsets and functional consequences of a novel tumour necrosis factor (TNF) receptor type 1 (TNFRSF1A) mutation affecting the receptor cleavage site. Methods: Patients with symptoms suggestive of tumour necrosis factor receptor-associated periodic syndrome (TRAPS) and 22 healthy controls (HC) were screened for mutations in the TNFRSF1A gene. Soluble TNFRSF1A and inflammatory cytokines were measured by ELISAs. TNFRSF1A shedding was examined by stimulation of peripheral blood mononuclear cells (PBMCs) with phorbol 12-myristate 13-acetate followed by flow cytometric analysis (FACS). Apoptosis of PBMCs was studied by stimulation with TNFa in the presence of cycloheximide and annexin V staining. T cell phenotypes were monitored by FACS. Results: TNFRSF1A sequencing disclosed a novel V173D/ p.Val202Asp substitution encoded by exon 6 in one family, the c.194–14G.A splice variant in another and the R92Q/p.Arg121Gln substitution in two families. Cardiovascular complications (lethal heart attack and peripheral arterial thrombosis) developed in two V173D patients. Subsequent etanercept treatment of the V173D carriers was highly effective over an 18-month follow-up period. Serum TNFRSF1A levels did not differ between TRAPS patients and HC, while TNFRSF1A cleavage from monocytes was significantly reduced in V173D and R92Q patients. TNFa-induced apoptosis of PBMCs and T-cell senescence were comparable between V173D patients and HC. Conclusions: The TNFRSF1A V173D cleavage site mutation may be associated with an increased risk for cardiovascular complications and shows a strong response to etanercept. T-cell senescence does not seem to have a pathogenetic role in affected patients

Pressure-induced enhancement of superconductivity and superconducting-superconducting transition in CaC_6\_6

We measured the electrical resistivity, $\varrho(T)$, of superconducting CaC$\_6$ at ambient and high pressure up to 16 GPa. For $P \leq$8 GPa, we found a large increase of $T\_c$ with pressure from 11.5 up to 15.1 K. At 8 GPa, $T\_c$ drops and levels off at 5 K above 10 GPa. Correspondingly, the residual $\varrho$ increases by $\approx$ 200 times and the $\varrho(T)$ behavior becomes flat. The recovery of the pristine behavior after depressurization is suggestive of a phase transition at 8 GPa between two superconducting phases with good and bad metallic properties, the latter with a lower $T\_c$ and more static disorder