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We describe a technique using a focused ion beam instrument to fabricate high quality plan-view specimens for transmission electron microscopy studies. The technique is simple, site-specific and is capable of fabricating multiple large, >100µm² electron transparent windows within epitaxially grown thin films. A film of La0.67Sr0.33MnO3 is used to demonstrate the technique and its structural and functional properties are surveyed by high resolution imaging, electron spectroscopy, atomic force microscopy and Lorentz electron microscopy. The window is demonstrated to have good thickness uniformity and a low defect density that does not impair the film's Curie temperature. The technique will enable the study of in-plane structural and functional properties of a variety of epitaxial thin film systems. [ABSTRACT FROM AUTHOR]

We have developed a chlorine based dry etching process for nanopatterning the ferromagnetic oxide La0.7Sr0.3MnO3 (LSMO). Large arrays of millions of identical structures have been fabricated from thin LSMO films by electron-beam lithography and reactive ion etching. SQUID magnetometry demonstrates that patterned nanostructures with lateral dimensions down to 100 nm retain their full magnetization and the Curie temperature of the bulk layer. In addition, their shape anisotropy is sufficient to overcome the crystalline anisotropy of the bulk. High resolution scanning transmission electron microscopy shows that crystallinity is preserved even at the edges of the nanostructures. [ABSTRACT FROM AUTHOR]

The adipokine adiponectin is decreased in severe obesity and is inversely associated with adipose mass. Adiponectin is associated with insulin sensitivity and cardioprotection. Obesity frequently results in the development of a “cardiometabolic syndrome” characterized by increased circulating insulin and leptin, and cardiac hypertrophy and dysfunction. This study examined if adiponectin-deficiency affects the development of metabolic and cardiac abnormalities in response to modest obesity. Mice were studied under normal conditions and with mild cardiac pressure-overload induced by abdominal aortic banding. After surgery, wild type and adiponectin-deficient mice were fed a high-fat diet for 8 weeks (45% energy from fat vs. 10%). In wild type mice the high-fat diet increased fat and whole body mass, which corresponded with elevated circulating insulin and leptin and a decrease the glucose/insulin ratio. On the other hand, in adiponectin-deficient mice the high-fat diet had less impact on body mass and no effect on fat mass, insulin, leptin, or glucose/insulin. There was modest cardiac hypertrophy with aortic banding, but no cardiac dysfunction or effects of adiponectin deficiency or diet. The results suggest that the increase in adipose mass, leptin and insulin induced by a high fat diet is dependent on adiponectin. The lack of accelerated cardiac hypertrophy and dysfunction in the adiponectin-deficient mice subjected to aortic banding and the high-fat diet suggest that adiponectin may not play a major role in protecting the heart during the early stages of diet-induced obesity. [ABSTRACT FROM AUTHOR]

We report on the onset of turbulence in normal and superfluid He using several 13.5 μm diameter vibrating wire resonators placed in a cell, filtered from the surrounding helium bath. We measured the force-velocity characteristics of the wires in normal and superfluid helium over a velocity range up to several meters per second. The transition from laminar to turbulent behavior can be clearly identified. Surprisingly we find that, depending on the cooling history, turbulence in the superfluid does not always develop fully. [ABSTRACT FROM AUTHOR]

BACKGROUND AND AIMS: An epidemiological analysis of cases of spontaneous community acquired septic arthritis in an elderly population at a university teaching hospital. METHODS: Confirmed cases of spontaneous septic arthritis in the over-65 population were studied. Patients with prosthetic joint infections were excluded from the study. Analysed data included initial presenting complaint and clinical examination, hematological and microbiological tests together with ultimate patient outcome. RESULTS: There were 7 confirmed cases of spontaneous septic arthritis in the over 65 population in the past 6 months (2 hips, 5 knees). The mean age was 72.14 (range 65-82) with a mean length of stay of 49 days. Those with septic arthritis of the knee presented with swelling, pain and immobility. Hip cases presented with pain and immobility. All patients were systemically well at the time of presentation, with no other foci of infection detected after septic screening. All patients had confirmed aspirate and arthroscopic/arthrotomy infection. Staphylococcus aureus was isolated from 6 joint aspirations and Pseudomonas Aeruginosa from one patient. Complications of treatment included acute renal failure, cardio/respiratory failure, disseminated infection, and death (1 case). CONCLUSION: Septic arthritis must be considered as a differential diagnosis in all patients with joint pain, swelling and immobility. This diagnosis is not confined to the pediatric population. A background of degenerative disease and occult presentation in the elderly may delay diagnosis. Sepsis must be considered in the elderly with joint pathology, and treatment must be initiated in a prompt and aggressive manner, to prevent sequelae. [ABSTRACT FROM AUTHOR]

Background and Objectives The low prevalence antigen, Bea, is produced by a complex that also produces weak c, e and f (ce). We report here the molecular basis associated with Bea antigen expression. Materials and Methods Peripheral blood samples from four Be(a+) probands were tested. Haemagglutination, gDNA extraction, PCR-based assays, reticulocyte RNA isolation, Rh-cDNA analyses, and sequencing were performed by standard procedures. Results RBCs from Probands 1 and 3 were D−C−E−c+e+, and from Probands 2 and 4 were D+C+E−c+We+. In proband 1, cDNA sequencing of RHCE revealed heterozygosity of nucleotide (nt) 662C/G in exon 5 of RHCE*ce. No other nucleotide changes were observed. As the 662C>G nucleotide change ablates a MscI restriction enzyme cleavage site, PCR–RFLP analysis was performed and the RHCE*ce nt 662C/G heterozygosity was detected on gDNA from the four probands and two children from both Proband 3 and Proband 4. Conclusion The low prevalence Rh antigen, Bea, is associated with a single nucleotide change in exon 5 of RHCE*ce; that of 662C>G and this change is predicted to alter proline at amino acid position 221 of Rhce to arginine. The fundamental differences in the properties of these two amino acids may impose a steric and/or charge-related effect on the protein, and thereby provide an explanation for the weakened expression of c, e and f (ce) antigens in the Bea phenotype. [ABSTRACT FROM AUTHOR]

Differentiation of the pluripotent neuroepithelium into neurons and glia is accomplished by the interaction of growth factors and cell-type restricted transcription factors. One approach to obtaining a particular neuronal phenotype is by recapitulating the expression of these factors in embryonic stem (ES) cells. Toward the eventual goal of auditory nerve replacement, the aim of the current investigation was to generate auditory nerve-like glutamatergic neurons from ES cells. Transient expression of Neurog1 promoted widespread neuronal differentiation in vitro; when supplemented with brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF), 75% of ES cell-derived neurons attained a glutamatergic phenotype after 5 d in vitro. Mouse ES cells were also placed into deafened guinea pig cochleae and Neurog1 expression was induced for 48 h followed by 26 d of BDNF/GDNF infusion. In vivo differentiation resulted in 50-75% of ES cells bearing markers of early neurons, and a majority of these cells had a glutamatergic phenotype. This is the first study to report a high percentage of ES cell differentiation into a glutamatergic phenotype and sets the stage for cell replacement of auditory nerve. [ABSTRACT FROM AUTHOR]

Objective To assess the interest, perceptions, and needs of primary care physicians with regard to office-based precepting of medical students. Design Random survey. Setting The New England region of the United States (Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut). Participants Family physicians, general internists and paediatricians. Main outcome measures These included: (1) practice and preceptor demographics; (2) Likert scale agreement or disagreement with various positive and negative perceptions about precepting students; rating (from unimportant to necessary) of potential benefits from medical schools associated with the support of precepting in the office setting, and (3) comparisons among physician groups to determine differences in perceptions and needs. Results There is a high level of interest in precepting regardless of primary care specialty, practice structure, payment mechanism, or precepting experience. Negative impacts included decreased productivity and increased length of the day by a median of 60 minutes. Positive impacts included keeping one's own knowledge up-to-date and enhanced enjoyment of practice. Benefits such as academic appointments, continuing medical education credits, faculty development, computer linkages for clinical information and medical library access are rated highly. Monetary payment, whether as a modest honorarium or as compensation for lost time/income, was felt to be important by half of our sample. Conclusion A significant interest in precepting medical students on a regular basis is expressed by primary care physicians in the ambulatory medicine setting. The results of this survey can be used by medical schools to address negative perceptions and to develop appropriate benefits packages to recruit and retain these primary care preceptors. [ABSTRACT FROM AUTHOR]

Despite the recent synthesis and identification of a diverse set of new nanophotocatalysts that has exploded recently, titanium dioxide (TiO2) remains among the most promising photocatalysts because it is inexpensive, non-corrosive, environmentally friendly, and stable under a wide range of conditions. TiO2 has shown excellent promise for solar cell applications and for remediation of chemical pollutants and toxins. Over the past few decades, there has been a tremendous development of nanophotocatalysts for a variety of industrial applications (i.e. for water purification and reuse, disinfection of water matrices, air purification, deodorization, sterilization of soils). This paper details traditional and new industrial routes for the preparation of nanophotocatalysts and the characterization techniques used to understand the physical chemical properties of them, like surface area, ζ potential, crystal size, and phase crystallographic, morphology, and optical transparency. Finally we present some applications of the industrial nanophotocatalysts.

Dimethyl methylphosphonate (DMMP) and diethyl methylphosphonate (DEMP) are readily mineralized by photoexcited titanium dioxide (TiO2). Intermediate products include low molecular weight organic acids and methylphosphonic acid. Complete mineralization yields phosphate and carbon dioxide. The photoactivities of different types of TiO2 were investigated. The decomposition kinetics of DMMP and effects of DMMP and catalyst concentration, sonication, solar irradiation, oxygen concentration, temperature, and hydrogen peroxide on the rate of decomposition are reported. The degradation rates increase with simultaneous sonication, addition of hydrogen peroxide, and at higher temperatures. [ABSTRACT FROM AUTHOR]

The carbonic anhydrase (CA)-like protein, CA VIII, lacks the typical carbon dioxide hydrase activity of the CA isozymes. However, the high degree of amino acid sequence similarity between the products of the mouse and the human CA VIII genes suggests an important biological function. We have attempted to investigate the function of this gene in mammalian development by conducting an in situ hybridization study on sagittal sections of mouse embryos at gestation days of 9.5–16.5 using a 35S-labelled riboprobe. Results indicate that this gene (called Car8 in mice) is expressed as early as day 9.5 in a variety of organs including liver, branchial arches, neuroepithelium and developing myocardium. Between days 10.5 and 12.5, it showed a widespread distribution of mRNA expression that became more restricted as development progressed. The level of expression of Car8 mRNA was relatively high in the brain, liver, lung, heart, gut, thymus and epithelium covering the head and the oronasal cavity. [ABSTRACT FROM AUTHOR]

Lorentz microscopy has been used to explore the structure variation of domain walls in thin Permalloy nanowires in the vicinity of symmetric triangular antinotches. The antinotches present a complex potential landscape to domain walls. Walls can be trapped in front of, partly enter, or be trapped inside the antinotches according to the geometry of the latter and, in the case of vortex domain walls, the chirality. In all cases, the magnetization distribution was determined. Of particular note was the structure the wall assumed during depinning from the antinotch, complex forms extending over distances several times the wire width being observed. [ABSTRACT FROM AUTHOR]