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In the Miocene, a large wetland extended from the Andean foothills into western Amazonia. This system plays an important part in current biogeographic models and is thought to have acted as an evolutionary ‘cradle’ for aquatic species and an ‘inhibitor’ for terrestrial taxa. The generating mechanisms of this system are not fully understood, but dynamic topography, Andean uplift and eustasy are all thought to have controlled deposition. Orbital forcing is likely an additional driver that could explain the succession of shallowing upwards cycles that characterize the sedimentary record. In this study we investigated the presumed cyclicity at the Los Chorros (Colombia), a site that constitutes a representative example for the sedimentary record in the Miocene wetland system. We integrated lithological, palynological and malacological data from a sequence biostratigraphic perspective. In this approach, the Los Chorros succession is visualised to be composed of a series of flood-fill packages, with a rapid initial flood, with marine-influenced conditions at the time of maximum flood, and followed by a longer regressive infill phase. Based on the palynology we could differentiate local vegetation, such as swamps, from sources of regional origin such as terra firme vegetation (non-flooded Amazonian Forest) and montane forest (Andean), while also separating local and regional sediment sources. Marine influences are intermittently evident in this section, based on the occurrence of short-lived maxima of mangrove pollen, foraminiferal test linings, dinoflagellate cysts, some mollusc species, and an episodic decline in terrestrial biomarkers. At the times of flooding, the lacustrine conditions in the wetland system were characterized by the presence of algae, floating ferns, and mollusc assemblages that indicate alternating oligotrophic and eutrophic conditions, while intervening subaquatic debris points to proximal submerged lowlands. The palynology also shows that the shallow lakes were fringed by a succession of Mauritiinae palm swamps, ferns, and grasses, with a diverse rainforest in the wider periphery. The sequence biostratigraphic evaluation suggests that the deposition of this sediment sequence took place prior to the 13.8 Ma global sea level fall, and most likely the period just after 14.5 Ma, towards the end of the Middle Miocene Climatic Optimum. We propose that the studied succession comprises eight 41 ka obliquity-driven depositional cycles, with rapid phases of transgression, and that mangrove elements would have colonised within the timeframe of each sea level rise.

Complex foot infections involving bone and soft tissue in patients with co-morbidities such as diabetes and peripheral arterial disease (PAD) are a cause of significant hospital admission. They are associated with substantial economic costs to health services worldwide. Historically, severe foot infection has been treated with surgical debridement and prolonged courses of systemic antibiotics. Prolonged systemic antibiotic use increases the risk of drug side effects, antimicrobial resistance and Clostridium difficile infection. The purpose of this study was to investigate whether surgical debridement and implantation of antibiotic loaded calcium sulfate is effective in the resolution of foot infection and wound healing. A retrospective cohort study of 137 consecutive cases of osteomyelitis (127) or significant soft tissue infection (10) over 62 months from 02/2013 to 04/2018 was conducted following local ethical approval. All cases of infection were treated with surgical debridement and local antibiotic-loaded calcium sulfate. The primary outcomes of infection resolution, time to healing and duration of postoperative antibiotics were measured. In 137 cases, 88.3% of infections resolved. Infection was eradicated in 22 patients without postoperative systemic antibiotics. About 82.5% of wounds healed, with an average healing time of 11.3 weeks. Healing time was significantly increased for the co-morbidities of diabetes and PAD (p =< .05) and for those requiring prolonged systemic postoperative antibiotics. Conservative surgical debridement and implantation of local antibiotic impregnated calcium sulfate is safe and effective in managing complex foot infections. We advocate early surgical intervention before deeper tissue involvement to help preserve lower limb structure and function.

Rapid access chest pain clinics have been introduced nationally to identify patients with new onset chest pain, thought to be angina, and investigate and treat according to evidence-based guidelines. The service improvement model used in this study has shown a dramatic reduction in waiting times for medium and high risk patients in referral for angiography and percutaneous coronary intervention using specific electrocardiographic criteria linked to the Bruce Protocol exercise tolerance test. Outcome data has shown that by using these criteria, patients can be listed directly for planned revascularization from the rapid access chest pain clinic thereby considerably reducing waiting times.

Treating diabetic foot infection is costly, time consuming and challenging for the patient and clinician alike. It requires a multidisciplinary approach to provide a favourable outcome but all too often results in amputation. We present a patient with Type 2 diabetes who attended clinic with a limb threatening foot infection complicated by osteomyelitis and requiring emergency surgery and antibiotic administration. Our patient underwent surgery by means of an incision and drainage procedure with local antibiotic administration to augment systemic antibiotics. The wound was packed with calcium sulphate (Stimulan(®) Biocomposites Ltd.) impregnated with gentamicin and vancomycin to enable high antibiotic concentrations at the site of infection. The patient made a full recovery at four months requiring only minimal bone excision to maintain a functional foot. This case demonstrates an alternative route for antibiotic administration to overcome some of the limitations of systemic administration including penetration at the site of infection, systemic toxicity, prolonged hospital admission and cost. This route of administration is being increasingly used as an alternative to systemic antibiotics at our centre.

The intercalation of n -propylamine, n -butylamine and ethylenediamine by the layered compound α-zirconium phosphate has been examined. Each of the amines forms a number of phases whose interlayer spacings are indicative of the orientation of the amines within the layers. At low uptakes of the n -alkyl amines, they appear to lie parallel to the layers. At higher contents a double layer forms with the carbon chain backbone roughly inclined at a 60° angle to the plane of the layer. A maximum of one n -alkyl amine molecule per phosphate group is intercalated. Half as much ethylenediamine is intercalated which constitutes the same number of amine-groups. The interlayer spacings indicate, however, that the ethylenediamine chain always lies parallel to the layer but in at least four different orientations, giving rise to as many phases.

The matching cloze procedure, which does not require language production skills and which is simple enough for the classroom teacher to construct unaided, was originally developed to measure reading skills of elementary English‐second‐language pupils. The results of this pilot study with opportunity school children indicate the validity of the procedure as an evaluation technique for slow learning children.

The study of buoyancy effects in enclosed jet systems is a much neglected field of combustion aerodynamics, research. Although theoretical analyses exist,little experimental data has been collected and this experimental investigation sets out to study the influence of various input momentum parameters on the deflection experienced by an enclosed buoyant jet. Due to the difficulty of modelling the jet under buoyant forces of sufficient magnitude,a technique has been used which was originally developed for free jet buoyancy studies. A slurry of finely ground Magnetite was used as a primary jet source whilst water was the fluid used for the general stream. Density ratios (Primary to secondary) of up to 2.7 have been used in the study whilst the velocity ratio was varied between 5 and 50, giving a range of Curtet numbers between 0.3 and 1.4. The resulting turbulent jet was photographed with a high speed 16mm. cine camera. From the film, measurements of jet enclosed angle, length of potential core, axial velocity and jet deflection were made. At the lower densities the jet angle was found to be constant for each density ratio, thus supporting the common assumption of constant entrainment rate, in jet systems where the variation in density of the jet fluid is small. However as the density ratio increased then it was found that the constant entrainment assumption was conditional on higher velocity ratios. Generally the assump tion only held for Curtet Numbers less than 0. 35. The axial velocity was found to decay significantly faster in the enclosed buoyant jet than predicted by the free jet theory. That this decay was a result of mixing and not input momentum was shown in the fact that varying the velocity ratio had a much greater effect than varying the density ratio. Greater mixing levels exist in the enclosed jet as compared to the free jet, a fact further borne out by the similarity of the potential core velocity ratio relation ship to that found in jets in cross streams where increased mixing is also experienced, although possibly not for the same reasons. An expression has been derived which can be used to predict, with some caution, the path of a jet issuing horizontally into an enclosed space with an initial density difference, up to the point where buoyancy control ceases, and the jet is no longer deflected. This point was found by experiment to be at s = 2.3/k. where k is an empirical constant from the expression for the axial velocity ratio. An attempt was made to model a flame envelope near the mixing tube wall and using the assumption that the envelope was enclosed by the half jet angle it was found that for velocity ratios less than approximately 10, this half jet contour would strike the mixing tube wall whilst the jet was still under the influence of the buoyancy forces.

The intercalation behaviour of α-zirconium phosphate, Zr(HPO4)2·H2O, towards n-alkylamines has been examined. Amines with small carbon chains (C1–C4) initially form a phase in which the chain backbone lies parallel to the zirconium phosphate layers. As more amine is intercalated the amines form a bilayer in which the carbon chains incline at roughly 60° to the zirconium phosphate layers. Methyl and propylamine form disordered gels at intermediate levels of intercalation but recrystallize at high levels of amie uptake. The longer-chain amines form a bilayer even at low uptakes. The wet intercalates contain 10–12 mol water per formula weight, mostly as interparticle water rearrangement. On drying to the monohydrates, the interlayer spacings do not change when the solids have a high amine content. At lower amine contents the amine rearranges to yield phases with lower interlayer spacings.