2,430 research outputs found

    Flow-cytometric quantification of microbial cells on sand from water biofilters

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    Rapid quantification of absolute microbial cell abundances is important for a comprehensive interpretation of microbiome surveys and crucial to support theoretical modelling and the design of engineered systems. In this paper, we propose a protocol specifically optimised for the quantification of microbial abundances in water biofilters using flow cytometry (FCM). We optimised cell detachment from sand biofilter particles for FCM quantification through the evaluation of five chemical dispersants (NaCl, Triton-X100, CaCl2, sodium pyrophosphate (PP), Tween 80 combined with PP), different mechanical pre-treatments (low and high energy sonication and shaking) and two fixation methods (glutaraldehyde and ethanol). The developed protocol was cross-compared using other established and commonly employed methods for biomass quantification in water filter samples (adenosine triphosphate (ATP) quantification, real-time quantitative PCR (qPCR) and volatile solids (VS)). The highest microbial count was obtained by detaching the biofilm from biofilter grains and dispersing clusters into singles cells using Tween 80 and sodium pyrophosphate combined with four steps of high energy sonication (27W, for 80 s each step); glutaraldehyde was shown to be the best fixative solution. The developed protocol was reliable and highly reproducible and produced results that are comparable to data from alternative quantification methods. Indeed, high correlations were found with trends obtained through ATP and qPCR (ρ = 0.98 and ρ = 0.91) measurements. The VS content was confirmed as an inaccurate method to express biomass in sand samples since it correlated poorly with all the other three methods (ρ = 0.005 with FCM, 0.002 with ATP and 0.177 with qPCR). FCM and ATP showed the strongest agreement between absolute counts with a slope of the correlation equal to 0.7, while qPCR seemed to overestimate cell counts by a factor of ten. The rapidity and reproducibility of the method developed make its application ideal for routine quantification of microbial cell abundances on sand from water biofilters and thus useful in revealing the ecological patterns and quantifying the metabolic kinetics involved in such systems

    Evanescent-wave trapping and evaporative cooling of an atomic gas near two-dimensionality

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    A dense gas of cesium atoms at the crossover to two-dimensionality is prepared in a highly anisotropic surface trap that is realized with two evanescent light waves. Temperatures as low as 100nK are reached with 20.000 atoms at a phase-space density close to 0.1. The lowest quantum state in the tightly confined direction is populated by more than 60%. The system offers intriguing prospects for future experiments on degenerate quantum gases in two dimensions

    Use of the physician orders for life-sustaining treatment program in the clinical setting: a systematic review of the literature

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    The Physician Orders for Life-Sustaining Treatment (POLST) form is a palliative care tool that contains standardized, actionable medical orders. It is designed to ensure that patient treatment preferences are elicited, communicated, and honored throughout the healthcare system. A systematic review of the literature was conducted to evaluate what is currently known about the POLST program and identify directions for future research. Twenty-three research studies focused on POLST use in the clinical setting were identified. A majority of studies have been conducted all or in part in Oregon, with chart review the most frequently used methodology. Research suggests that POLST is most commonly used in older, white patients who are near the end of life. A nonphysician facilitator usually prepares the POLST form for the physician to review and sign. The orders documented on POLST reflect a wide degree of individualization, with only approximately one-third of patients having orders reflecting the lowest level of treatment in all POLST form sections. Clinicians have generally positive attitudes regarding use of POLST yet report a wide range of challenges. POLST alters treatment in a way that is consistent with orders. However, evidence that POLST reflects patient or surrogate treatment preferences is lacking. Research is needed to evaluate the quality of POLST decisions, explore the experiences of patients and their surrogates, develop decision-support tools, improve clinician education, and assess the effect of POLST on care outcomes through intervention and population-based studies

    Cold atom gas at very high densities in an optical surface microtrap

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    An optical microtrap is realized on a dielectric surface by crossing a tightly focused laser beam with an horizontal evanescent-wave atom mirror. The nondissipative trap is loaded with \sim10510^5 cesium atoms through elastic collisions from a cold reservoir provided by a large-volume optical surface trap. With an observed 300-fold local increase of the atomic number density approaching 1014cm310^{14}{\rm cm}^{-3}, unprecedented conditions of cold atoms close to a surface are realized

    Profound Leadership: An Integrative Literature Review

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    This integrative literature review develops the concept of profound leadership. Using Torraco’s (2005, 2016) framework for integrative literature reviews as a foundation, the purpose of this study is threefold: (a) to review existing leadership theories fitting the profound learning framework (Kroth, 2016; Name deleted to maintain the integrity of the review process; Name deleted to maintain the integrity of the review process); (b) to examine the leadership theory definitions, characteristics, and dependent variables; and (c) to apply the outcomes of (a) and (b) to build the theory of profound leadership and make recommendations for future theory-building. Leadership as a general concept has been extensively explored, researched, and written about, developing a rich palette of explanatory theories. Profound leadership, on the other hand, is an emerging concept to elaborate through this integrative review of literature of specific leadership theories resonating with profound learning

    Profound Leadership: An Integrative Literature Review

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    This integrative literature review develops the concept of profound leadership. Using Torraco’s (2005, 2016) framework for integrative literature reviews as a foundation, the purpose of this study is threefold: (a) to review existing leadership theories fitting the profound learning framework (Kroth, 2016; Name deleted to maintain the integrity of the review process; Name deleted to maintain the integrity of the review process); (b) to examine the leadership theory definitions, characteristics, and dependent variables; and (c) to apply the outcomes of (a) and (b) to build the theory of profound leadership and make recommendations for future theory-building. Leadership as a general concept has been extensively explored, researched, and written about, developing a rich palette of explanatory theories. Profound leadership, on the other hand, is an emerging concept to elaborate through this integrative review of literature of specific leadership theories resonating with profound learning

    Profound Leadership and Adult Education: An integrative Review of the Literature

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    This integrative literature review presents profound leadership through the lens of key characteristics of servant leadership, authentic leadership, level five leadership, profound leadership, transformational leadership, and spiritual leadership

    Use of the Physician Orders for Scope of Treatment Program in Indiana Nursing Homes

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    OBJECTIVES: To assess the use of the Indiana Physician Orders for Scope of Treatment (POST) form to record nursing home (NH) resident treatment preferences and associated practices. DESIGN: Survey. SETTING: Indiana NHs. PARTICIPANTS: Staff responsible for advance care planning in 535 NHs. MEASUREMENTS: Survey about use of the Indiana POST, related policies, and educational activities. METHODS: NHs were contacted by telephone or email. Nonresponders were sent a brief postcard survey. RESULTS: Ninety-one percent (n=486) of Indiana NHs participated, and 79% had experience with POST. Of the 65% of NHs that complete POST with residents, 46% reported that half or more residents had a POST form. POST was most often completed at the time of admission (68%). Only 52% of participants were aware of an existing facility policy regarding use of POST; 80% reported general staff education on POST. In the 172 NHs not using POST, reasons for not using it included unfamiliarity with the tool (23%) and lack of facility policies (21%). CONCLUSION: Almost 3 years after a grassroots campaign to introduce the voluntary Indiana POST program, a majority of NHs were using POST to support resident care. Areas for improvement include creating policies on POST for all NHs, training staff on POST conversations, and considering processes that may enhance the POST conversation, such as finding an optimal time to engage in conversations about treatment preferences other than a potentially rushed admission process

    Cavity-Modulated Proton Transfer Reactions

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    Proton transfer is ubiquitous in many fundamental chemical and biological processes, and the ability to modulate and control the proton transfer rate would have a major impact on numerous quantum technological advances. One possibility to modulate the reaction rate of proton transfer processes is given by exploiting the strong light-matter coupling of chemical systems inside optical or nanoplasmonic cavities. In this work, we investigate the proton transfer reactions in the prototype malonaldehyde and Z-3-amino-propenal (aminopropenal) molecules using different quantum electrodynamics methods, in particular, quantum electrodynamics coupled cluster theory and quantum electrodynamical density functional theory. Depending on the cavity mode polarization direction, we show that the optical cavity can increase the reaction energy barrier by 10–20% or decrease the reaction barrier by ∼5%. By using first-principles methods, this work establishes strong light-matter coupling as a viable and practical route to alter and catalyze proton transfer reactions

    Use of the Physician Orders for Life-Sustaining Treatment Program for Patients Being Discharged from the Hospital to the Nursing Facility

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    Background: The Physician Orders for Life-Sustaining Treatment (POLST) documents patient preferences as medical orders that transfer across settings with patients., Objectives: The objectives were to pilot test methods and gather preliminary data about POLST including (1) use at time of hospital discharge, (2) transfers across settings, and (3) consistency with prior decisions., Study Design: Descriptive with chart abstraction and interviews., Participants: Participants were hospitalized patients discharged to a nursing facility and/or their surrogates in La Crosse County, Wisconsin., Measurements: POLST forms were abstracted from hospital records for 151 patients. Hospital and nursing facility chart data were abstracted and interviews were conducted with an additional 39 patients/surrogates., Results: Overall, 176 patients had valid POLST forms at the time of discharge from the hospital, and many (38.6%; 68/176) only documented code status. When the whole POLST was completed, orders were more often marked as based on a discussion with the patient and/or surrogate than when the form was used just for code status (95.1% versus 13.8%, p<.001). In the follow-up and interview sample, a majority (90.6%; 29/32) of POLST forms written in the hospital were unchanged up to three weeks after nursing facility admission. Most (71.9%; 23/32) appeared consistent with patient or surrogate recall of prior treatment decisions., Conclusion: POLST forms generated in the hospital do transfer with patients across settings, but are often used only to document code status. POLST orders appeared largely consistent with prior treatment decisions. Further research is needed to assess the quality of POLST decisions
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