627 research outputs found

    Multiple functions of Na/K-ATPase in dopamine-induced salivation of the Blacklegged tick, Ixodes scapularis

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    Citation: Kim, D., Urban, J., Boyle, D. L., & Park, Y. (2016). Multiple functions of Na/K-ATPase in dopamine-induced salivation of the Blacklegged tick, Ixodes scapularis. Scientific Reports, 6, 13. doi:10.1038/srep21047Control of salivary secretion in ticks involves autocrine dopamine activating two dopamine receptors: D1 and Invertebrate-specific D1-like dopamine receptors. In this study, we investigated Na/K-ATPase as an important component of the secretory process. Immunoreactivity for Na/K-ATPase revealed basal infolding of lamellate cells in type-I, abluminal interstitial (epithelial) cells in type-II, and labyrinth-like infolding structures opening towards the lumen in type-III acini. Ouabain (10 mu mol l(-1)), a specific inhibitor of Na/K-ATPase, abolished dopamine-induced salivary secretion by suppressing fluid transport in type III acini. At 1 mu mol l(-1), ouabain, the secreted saliva was hyperosmotic. This suggests that ouabain also inhibits an ion resorptive function of Na/K-ATPase in the type I acini. Dopamine/ouabain were not involved in activation of protein secretion, while dopamine-induced saliva contained constitutively basal level of protein. We hypothesize that the dopamine-dependent primary saliva formation, mediated by Na/K-ATPase in type III and type II acini, is followed by a dopamine-independent resorptive function of Na/K-ATPase in type I acini located in the proximal end of the salivary duct

    Characterization and comparison of lesions on ornamental sweetpotato 'Blackie', tomato 'Maxifort', interspecific geranium 'Caliente Coral', and bat-faced cuphea 'Tiny Mice'.

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    Many plant species are prone to physiological disorders in which lesions develop on the leaf tissue. Nomenclature for such lesions has included intumescences, excrescences, neoplasms, galls, genetic tumors, enations, and oedemata. Interchangeably using these terms causes confusion as to whether these names refer to the same or different disorders. Two of the most commonly used names are oedema and intumescence. The objective of this research was to characterize the development of lesions on ornamental sweetpotato (Ipomoea batatas ‘Blackie’), tomato (Solanum lycopersicum ‘Maxifort’), interspecific hybrid geranium(Pelargonium· ‘CalienteCoral’), and bat-faced cuphea (Cuphea llavea ‘TinyMice’) to determine similarities and differences in morphology and nomenclature among these physiological disorders. Light microscopy was used to characterize differences in cross-sectional height, width, and area of lesions on each species. Additionally, leaf tissue samples were embedded in paraffin, and 10-mm cross-sections were stained with Toluidine blue O and observed using light microscopy to identify specific cell layers involved with lesion development. Field emission scanning electron microscopy (SEM) and digital photography were used to observe the microscopic and macroscopic stages of lesion development, respectively, on each species. The lesions observed on ornamental sweetpotato were significantly greater in height and area than on the other three species, whereas tomato lesions were significantly greater in width. Lesions on ornamental sweetpotato and bat-faced cuphea occurred predominantly on the adaxial surface of the leaf, whereas lesions on geraniumand tomato occurred predominantly on the abaxial surface.With lesions on tomato, ornamental sweetpotato, and bat-faced cuphea, the epidermis was often subjected to the same hypertrophy apparent in the underlying parenchyma cells, ultimately allowing for greater cell expansion. However, in geranium, the epidermis resisted the expansion of the underlying cells, resulting in the eventual tearing of this tissue layer. Previous research indicates that lesion development on geranium is closely related to water status within the plant and may result in a wound response or provide a means of facilitated gas exchange. On the contrary, development of lesions on ornamental sweetpotato and tomato is believed to involve light quality. Based on these results and observations, two disorders occur across these species. The term "intumescence’’ should be used when referring to abnormal lesions on ornamental sweetpotato and tomato, and the term ‘‘oedema’’ should be used when referring to lesions on geranium. The term ‘‘intumescence’’ should also be used when referring to bat-faced cuphea lesions resulting from the morphological and anatomical aspects of these lesions closely resembling development on ornamental sweetpotato and tomato. Future research should investigate the role of light quality regarding development on this species

    Microbial flora of commercially produced vacuum packaged, cooked beef roast

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    Commercially produced vacuum packaged, fully cooked, microwaveable beef roasts from four producers were purchased from local retail markets. Salt concentration, pH, water activity (aw), and percent moisture, fat and protein were determined. Samples of both package juice and homogenized beef plus juice were analyzed for the presence of aerobic, anaerobic and lactic acid bacteria and clostridia-type organisms. The cooked beef products had pH values from 5.82 to 6.19, water activity of 0.992 to 0.997, and contained 0.34 to 1.07% salt, 61.89 to 72.39% moisture, 4.29 to 18.21% fat and 15.92 to 20.62% protein. No growth was detected in juice for aerobic, anaerobic or lactic acid bacteria or clostridia-type organisms. Combined beef and juice had less than 2 CFU/g for aerobic, anaerobic or lactic acid bacteria or clostridia-type organisms. Cooking and chilling schedules used in the manufacture of the four products we evaluated in this study limited survival and outgrowth of microorganisms

    A Spectroscopic Survey of Faint Quasars in the SDSS Deep Stripe: I. Preliminary Results from the Co-added Catalog

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    In this paper we present the first results of a deep spectroscopic survey of faint quasars in the Sloan Digital Sky Survey (SDSS) Southern Survey, a deep survey carried out by repeatedly imaging a 270 deg^2 area. Quasar candidates were selected from the deep data with good completeness over 0<z<5, and 2 to 3 magnitudes fainter than the SDSS main survey. Spectroscopic follow-up was carried out on the 6.5m MMT with Hectospec. The preliminary sample of this SDSS faint quasar survey (hereafter SFQS) covers ~ 3.9 deg^2, contains 414 quasars, and reaches g=22.5. The overall selection efficiency is ~ 66% (~ 80% at g<21.5); the efficiency in the most difficult redshift range (2<z<3) is better than 40%. We use the 1/V_{a} method to derive a binned estimate of the quasar luminosity function (QLF) and model the QLF using maximum likelihood analysis. The best model fits confirm previous results showing that the QLF has steep slopes at the bright end and much flatter slopes (-1.25 at z<2.0 and -1.55 at z>2.0) at the faint end, indicating a break in the QLF slope. Using a luminosity-dependent density evolution model, we find that the quasar density at M_{g}<-22.5 peaks at z~2, which is later in cosmic time than the peak of z~2.5 found from surveys of more luminous objects. The SFQS QLF is consistent with the results of the 2dF QSO Redshift Survey, the SDSS, and the 2dF-SDSS LRG and QSO Survey, but probes fainter quasars. We plan to obtain more quasars from future observations and establish a complete faint quasar sample with more than 1000 objects over 10 deg^2.Comment: 25 pages, 13 figures, accepted for publication in A

    A Content Analysis of Catholic School Written Discipline Policies

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    School discipline has traditionally endorsed the use of exclusionary practices (i.e. suspension and expulsion). Such practices can have a negative short- and long-term impact on student lives, and tend to be enforced disproportionately with certain student populations. Although public school discipline policies have received increased scrutiny in recent years, Catholic school policies have received very little attention. This study presents the results of a content analysis of the written discipline policies of 33 Catholic secondary schools from two dioceses within a major metropolitan area. Results suggest that although variability exists in the types of behaviors included in formal written policies, schools in this sample rely heavily on exclusionary practices as possible consequences to many behaviors, even relatively minor ones. Further, they include positive or restorative consequences minimally, if at all. Suggestions for future research related to discipline practices in Catholic schools are made

    Improving the quality of weekend medical handover on non-receiving medical hospital wards

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    INTRODUCTION: Handover is the system by which the responsibility for immediate and ongoing care is transferred between healthcare professionals and can be an area of risk. The Royal College of Physicians (RCP) has recommended improvement and standardisation of handover. Locally, national training surveys have reported poor feedback regarding handover at Glasgow Royal Infirmary. AIM: To improve and standardise handover from weekday to weekend teams. METHODS: The Plan–Do–Study–Act (PDSA) quality improvement framework was used. Interventions were derived from a driver diagram after consultation with relevant stakeholders. Four PDSA cycles were completed over a 4-month period: PDSA cycle 1—Introduction of standardised paper form on three wards. PDSA cycle 2—Introduction of electronic handover system on three wards. PDSA cycle 3—Expansion of electronic handover to seven wards. PDSA cycle 4—Expansion of electronic handover to all non-receiving medical wards. The outcome of interest was the percentage of patients with full information handed over based on a six-point scale derived from the RCP. Data were collected weekly throughout the study period. RESULTS: 18 data collection exercises were performed including 525 patients. During the initial phase there was an improvement in handover quality with 0/28 (0%) at baseline having all six points completed compared with 13/48 (27%) with standardised paper form and 21/42 (50%) with the electronic system (p<0.001). When the electronic handover form was expanded to all wards, the increased quality was maintained, however, to a lesser extent compared with the initial wards. CONCLUSION: A standardised electronic handover system was successfully introduced to downstream medical wards over a short time period. This led to an in improvement in the quality of handover in the initial wards involved. When expanded to a greater number of wards there was still an improvement in quality but to a lesser degree

    MF2293

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    Fadi Aramouni et al, Food safety, Kansas State University, October 1997

    Radio Observations of the Hubble Deep Field South region: I. Survey Description and Initial Results

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    This paper is the first of a series describing the results of the Australia Telescope Hubble Deep Field South (ATHDFS) radio survey. The survey was conducted at four wavelengths - 20, 11, 6, and 3 cm, over a 4-year period, and achieves an rms sensitivity of about 10 microJy at each wavelength. We describe the observations and data reduction processes, and present data on radio sources close to the centre of the HDF-S. We discuss in detail the properties of a subset of these sources. The sources include both starburst galaxies and galaxies powered by an active galactic nucleus, and range in redshift from 0.1 to 2.2. Some of them are characterised by unusually high radio-to-optical luminosities, presumably caused by dust extinction.Comment: Accepted by AJ. 32 pages, 4 tables, 3 figures. PDF with full-resolution figures is on http://www.atnf.csiro.au/people/rnorris/N197.pd
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