Direct observations of structural phase transitions in planar crystallized ion plasmas

Laser-cooled 9Be+ ions confined in two-dimensionally extended lattice planes were directly observed, and the images were used to characterize the structural phases of the ions. Five different stable crystalline phases were observed, and the energetically favored structure could be sensitively tuned by changing the areal density of the confined ions. The experimental results are in good agreement with theoretical predictions for the planar (infinite in two dimensions) one-component plasma. Qualitatively similar structural phase transitions occur, or are predicted to occur, in other experimentally realizable planar systems.     

An approximately 15,000-year record of El Nino-driven alluviation in southwestern ecuador

Debris flows have deposited inorganic laminae in an alpine lake that is 75 kilometers east of the Pacific Ocean, in Ecuador. These storm-induced events were dated by radiocarbon, and the age of laminae that are less than 200 years old matches the historic record of El Nino events. From about 15,000 to about 7000 calendar years before the present, the periodicity of clastic deposition is greater than or equal to 15 years; thereafter, there is a progressive increase in frequency to periodicities of 2 to 8.5 years. This is the modern El Nino periodicity, which was established about 5000 calendar years before the present. This may reflect the onset of a steeper zonal sea surface temperature gradient, which was driven by enhanced trade winds.     

High-level gentamicin-resistant and vancomycin-resistant Enterococcus faecium isolated from a wound in a dog

This report describes the first clinical case, in Europe, of a high-level gentamicin-resistant and vancomycin-resistant Enterococcus faecium infection in a dog. The aim of this report is to alert the veterinary profession to high-level gentamicin-resistant and vancomycin-resistant Enterococcus faecium in companion animal patients. Multi-drug resistant strains of this pathogen are the cause of considerable problems in human hospitals and for community healthcare professionals worldwide. The potential for a similar impact within veterinary medicine is discussed.     

Clinical behavior of intraocular teratoid medulloepithelioma in two‐related Quarter Horses

The objective of this paper is to describe clinical behavior, histopathologic features, and immunohistochemical staining of two‐related horses with intraocular teratoid medulloepithelioma. Two‐related Quarter Horses with similar intraocular masses presented to the UF‐CVM Comparative Ophthalmology Service for evaluation and treatment. The first horse, a 3‐year‐old gelding, had glaucoma and a cyst‐like mass in the anterior chamber. Enucleation was performed. Histopathology revealed a teratoid medulloepithelioma. The tumor was considered to be completely excised. Fifteen months later, the gelding presented with swelling of the enucleated orbit and local lymph nodes with deformation of the skull. Cytology revealed neuroectodermal neoplastic cells. Necropsy confirmed tumor metastasis. Six weeks later, a 9‐year‐old mare, a full sibling to the gelding, presented for examination. An infiltrative mass of the iris and ciliary body was found that extended into the anterior, posterior, and vitreal chambers. Uveitis was present, but secondary glaucoma was not noted. Enucleation was performed and the histopathologic diagnosis was also teratoid medulloepithelioma. The mare has had no recurrence to date, 2 years following enucleation. Metastasis of intraocular teratoid medulloepithelioma is possible. Staging is recommended in cases where the diagnosis of teratoid medulloepithelioma is confirmed. Surveillance of full siblings is recommended until more information regarding etiology is known.     

Mitral valve repair in dogs using an ePTFE chordal implantation device: a pilot study

Objective

Mitral valve (MV) regurgitation due to degenerative MV disease is the leading cause of cardiac death in dogs. We carried out preliminary experiments to determine the feasibility and short-term effects of beating-heart MV repair using an expanded polytetrafluorethylene (ePTFE) chordal implantation device (Harpoon TSD-5) in dogs.

High-flux solar-driven thermochemical dissociation of CO2 and H2O using nonstoichiometric ceria

Because solar energy is available in large excess relative to current rates of energy consumption, effective conversion of this renewable yet intermittent resource into a transportable and dispatchable chemical fuel may ensure the goal of a sustainable energy future. However, low conversion efficiencies, particularly with CO(2) reduction, as well as utilization of precious materials have limited the practical generation of solar fuels. By using a solar cavity-receiver reactor, we combined the oxygen uptake and release capacity of cerium oxide and facile catalysis at elevated temperatures to thermochemically dissociate CO(2) and H(2)O, yielding CO and H(2), respectively. Stable and rapid generation of fuel was demonstrated over 500 cycles. Solar-to-fuel efficiencies of 0.7 to 0.8% were achieved and shown to be largely limited by the system scale and design rather than by chemistry.     

Changes of Connexin43 Expression in Non‐pregnant Porcine Myometrium Correlate with Progesterone Concentration During Oestrous Cycle

Connexin43 (Cx43) is a major protein of myometrial gap junctions. The number of Cx43 gap junctions increase dramatically with the onset of labour in association with development of synchronized uterine contractions. The formation of myometrial gap junctions follows an increase in the oestrogen to progesterone ratio indicating an important role of steroid hormones in regulating Cx43 expression at term. However, no relationship has been established between the expression of Cx43 in the non‐pregnant myometrium and concentration of steroid hormones during the oestrous cycle. Here, we used immunofluorescence and Western blotting to analyse the expression of Cx43 gap junctions in the myometrium of pre‐pubertal pigs (n = 7) and mature pigs at pre‐ovulatory (n = 7), luteal (n = 5) and late luteal (n = 3) stages of the oestrous cycle. The number of Cx43 gap junctions calculated per 1 mm² of the myometrial section was low in pre‐pubertal pigs and significantly higher (p < 0.022) in pre‐ovulatory animals. In relation to pre‐ovulatory animals the number of myometrial gap junctions was significantly lower (p < 0.019) at the luteal phase and correlated with significantly higher (p < 0.005) concentration of endogenous progesterone. Phosphorylated isoforms of Cx43 protein were expressed in the myometrium of pre‐pubertal pigs and mature animals at pre‐ovulatory and late luteal phases, while they were down regulated at the luteal stage. These results indicate that changes of Cx43 expression in the porcine myometrium during the oestrous cycle may be regulated by progesterone concentration and may contribute to the modulation of uterine motility.     

Localization of Transforming Growth Factor Beta3 in Squamous Metaplasia of the Porcine Oviduct: a Case Report

Squamous metaplasia of the oviduct epithelium is a rare disorder of reproductive organs. We noted squamous metaplasia of the oviduct epithelium in a sow routinely slaughtered at day 2 of the oestrous cycle. Expression of transforming growth factor beta3 (TGF beta3) in the metaplastic epithelia was evaluated by immunohistochemistry, because TGF beta3 appears to play a key role as regulator of a variety of tissue remodelling events. Our results show that TGF beta3 immunostaining was specifically localized to foci of squamous metaplasia of the epithelial linings. Non‐metaplastic epithelial cells of the oviduct were not immunostained with anti‐TGF beta3 antibody. At the subcellular level, TGF beta3‐labelled cells occasionally showed signs of apoptotic cell death. It is concluded that signals produced by TGF beta3 in metaplastic lesions of the oviduct are potentially involved in pathophysiological processes.     

Multiple‐drug resistant Acinetobacter baumannii bronchopneumonia in a colt following intensive care treatment

This report describes a case of a multiple‐drug resistant strain of Acinetobacter baumannii associated with bronchopneumonia in a horse. A 6‐month‐old Thoroughbred colt was examined for a chronic lower respiratory tract disease. Prior to presentation to the University Veterinary Teaching Hospital (UVTH), the colt had been treated intensively in a private equine hospital for presumed antimicrobial‐induced enterocolitis following treatment with azithromycin and rifampin, and had been discharged on treatment of doxycycline for continued lower airway abnormalities. At the UVTH, investigation of the lower airway disease included a culture of a percutaneous transtracheal wash, which identified a multiple‐drug resistant strain of A. baumannii as the causative agent with sensitivity only to fluoroquinolones and trimethoprim sulphonamides. Following treatment with marbofloxacin there was full resolution of the bronchopneumonia. A. baumannii is a major nosocomial pathogen associated with infections in both animals and man and reports of multiple‐drug resistant strains have been documented worldwide. Outbreaks of A. baumannii infections have been reported to occur in very ill human patients housed in healthcare settings such as intensive care units, and are characterised by the rapid development of resistance to the majority of antimicrobials. The difficulties in the treatment of such cases as well as the potential risk of transmission within a veterinary clinical setting are discussed.