224 research outputs found

    Zeptonewton force sensing with nanospheres in an optical lattice

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    Optically trapped nanospheres in high-vaccum experience little friction and hence are promising for ultra-sensitive force detection. Here we demonstrate measurement times exceeding 10510^5 seconds and zeptonewton force sensitivity with laser-cooled silica nanospheres trapped in an optical lattice. The sensitivity achieved exceeds that of conventional room-temperature solid-state force sensors, and enables a variety of applications including electric field sensing, inertial sensing, and gravimetry. The optical potential allows the particle to be confined in a number of possible trapping sites, with precise localization at the anti-nodes of the optical standing wave. By studying the motion of a particle which has been moved to an adjacent trapping site, the known spacing of the lattice anti-nodes can be used to calibrate the displacement spectrum of the particle. Finally, we study the dependence of the trap stability and lifetime on the laser intensity and gas pressure, and examine the heating rate of the particle in high vacuum in the absence of optical feedback cooling.Comment: 5 pages, 4 figures, minor changes, typos corrected, references adde

    Leading with Wellness in Mind: Lessons in Academic Leadership During a Pandemic

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    PURPOSE: COVID-19 pandemic impact on healthcare providers has been immense, making it clear that the pandemic demands even more out of our leadership and wellness efforts. METHODS: We ground this work in the phenomenology of leadership. Our team evaluated programmatic interventions of virtual community wellness sessions. RESULTS: Ninety-eight percent of respondents strongly agreed that wellness initiatives in the department are critical. Qualitative results focus on one of the lessons learned; what it means to lead with wellness in mind. CONCLUSION: Now, more than ever, leading with wellness in mind becomes a high priority. We present its seven key domains

    Genomic approaches to research in pulmonary hypertension

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    Genomics, or the study of genes and their function, is a burgeoning field with many new technologies. In the present review, we explore the application of genomic approaches to the study of pulmonary hypertension (PH). Candidate genes, important to the pathobiology of the disease, have been investigated. Rodent models enable the manipulation of selected genes, either by transgenesis or targeted disruption. Mutational analysis of genes in the transforming growth factor-β family have proven pivotal in both familial and sporadic forms of primary PH. Finally, microarray gene expression analysis is a robust molecular tool to aid in delineating the pathobiology of this disease

    Contribution of thirdhand smoke to overall tobacco smoke exposure in pediatric patients: study protocol.

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    BackgroundThirdhand smoke (THS) is the persistent residue resulting from secondhand smoke (SHS) that accumulates in dust, objects, and on surfaces in homes where tobacco has been used, and is reemitted into air. Very little is known about the extent to which THS contributes to children's overall tobacco smoke exposure (OTS) levels, defined as their combined THS and SHS exposure. Even less is known about the effect of OTS and THS on children's health. This project will examine how different home smoking behaviors contribute to THS and OTS and if levels of THS are associated with respiratory illnesses in nonsmoking children.MethodsThis project leverages the experimental design from an ongoing pediatric emergency department-based tobacco cessation trial of caregivers who smoke and their children (NIHR01HD083354). At baseline and follow-up, we will collect urine and handwipe samples from children and samples of dust and air from the homes of smokers who smoke indoors, have smoking bans or who have quit smoking. These samples will be analyzed to examine to what extent THS pollution at home contributes to OTS exposure over and above SHS and to what extent THS continues to persist and contribute to OTS in homes of smokers who have quit or have smoking bans. Targeted and nontargeted chemical analyses of home dust samples will explore which types of THS pollutants are present in homes. Electronic medical record review will examine if THS and OTS levels are associated with child respiratory illness. Additionally, a repository of child and environmental samples will be created.DiscussionThe results of this study will be crucial to help close gaps in our understanding of the types, quantity, and clinical effects of OTS, THS exposure, and THS pollutants in a unique sample of tobacco smoke-exposed ill children and their homes. The potential impact of these findings is substantial, as currently the level of risk in OTS attributable to THS is unknown. This research has the potential to change how we protect children from OTS, by recognizing that SHS and THS exposure needs to be addressed separately and jointly as sources of pollution and exposure.Trial registrationClinicalTrials.gov Identifier: NCT02531594 . Date of registration: August 24, 2015

    Spatial and Temporal Analysis of Gene Expression during Growth and Fusion of the Mouse Facial Prominences

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    Orofacial malformations resulting from genetic and/or environmental causes are frequent human birth defects yet their etiology is often unclear because of insufficient information concerning the molecular, cellular and morphogenetic processes responsible for normal facial development. We have, therefore, derived a comprehensive expression dataset for mouse orofacial development, interrogating three distinct regions – the mandibular, maxillary and frontonasal prominences. To capture the dynamic changes in the transcriptome during face formation, we sampled five time points between E10.5–E12.5, spanning the developmental period from establishment of the prominences to their fusion to form the mature facial platform. Seven independent biological replicates were used for each sample ensuring robustness and quality of the dataset. Here, we provide a general overview of the dataset, characterizing aspects of gene expression changes at both the spatial and temporal level. Considerable coordinate regulation occurs across the three prominences during this period of facial growth and morphogenesis, with a switch from expression of genes involved in cell proliferation to those associated with differentiation. An accompanying shift in the expression of polycomb and trithorax genes presumably maintains appropriate patterns of gene expression in precursor or differentiated cells, respectively. Superimposed on the many coordinated changes are prominence-specific differences in the expression of genes encoding transcription factors, extracellular matrix components, and signaling molecules. Thus, the elaboration of each prominence will be driven by particular combinations of transcription factors coupled with specific cell:cell and cell:matrix interactions. The dataset also reveals several prominence-specific genes not previously associated with orofacial development, a subset of which we externally validate. Several of these latter genes are components of bidirectional transcription units that likely share cis-acting sequences with well-characterized genes. Overall, our studies provide a valuable resource for probing orofacial development and a robust dataset for bioinformatic analysis of spatial and temporal gene expression changes during embryogenesis

    Cost‐effectiveness of real‐world administration of tobacco pharmacotherapy in the United States Veterans Health Administration

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    Background and aimsCost‐effectiveness studies in randomized clinical trials have shown that tobacco cessation pharmacotherapy is among the most cost‐effective of health‐care interventions. Clinical trial eligibility criteria and treatment protocols may not be followed in actual practice. This study aimed to determine whether tobacco cessation pharmacotherapy is cost‐effective in real‐world settings.DesignA retrospective analysis of costs and outcomes.SettingHospitals and clinics of the US Veterans Health Administration, USA.ParticipantsA total of 589 862 US veterans who screened positive for tobacco use in 2011.Intervention and comparatorTobacco users who initiated smoking cessation pharmacotherapy in the 6 months after screening were compared with those who did not use pharmacotherapy in this period. Pharmacotherapy included nicotine replacement therapy, bupropion (if prescribed at 300 mg per day or specifically for tobacco cessation) or varenicline.MeasuresEffectiveness was determined from responses to a subsequent tobacco screening conducted between 7 and 18 months after the treatment observation period. Cost of medications and prescribing health‐care encounters was determined for the period between initial and follow‐up tobacco use screening. Multivariate fixed‐effects regression was used to assess the effect of initial treatment status on cost and outcome while controlling for differences in case‐mix with propensity weighting to adjust for confounding by indication.FindingsThirteen per cent of participants received tobacco cessation pharmacotherapy within 6 months of initial screening. After an average of an additional 218.1 days’ follow‐up, those who initially received pharmacotherapy incurred 143.79inadditionaltreatmentcostandhada3.1143.79 in additional treatment cost and had a 3.1% absolute increase in tobacco quit rates compared with those who were not initially treated. This represents an incremental cost‐effectiveness ratio of 4705 per quit. The upper limit of the 99.9% confidence region was 5600perquit.Withoutpropensityadjustment,thecosteffectivenessratiowas5600 per quit. Without propensity adjustment, the cost‐effectiveness ratio was 7144 per quit, with the upper limit of the 99.9% confidence region 9500/quit.ConclusionsTobaccocessationpharmacotherapyprovidedbytheUSVeteransHealthAdministrationin2011/12wascosteffectiveinthisrealworldsetting,withanincrementalcosteffectivenessratioof9500/quit.ConclusionsTobacco cessation pharmacotherapy provided by the US Veterans Health Administration in 2011/12 was cost‐effective in this real‐world setting, with an incremental cost‐effectiveness ratio of 4705 per quit.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/150598/1/add14621_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/150598/2/add14621.pd

    Genetics and genomics of pulmonary arterial hypertension

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    Major discoveries have been obtained within the last decade in the field of hereditary predisposition to pulmonary arterial hypertension (PAH). Among them, the identification of bone morphogenetic protein receptor type 2 (BMPR2) as the major predisposing gene and activin A receptor type II-like kinase-1 (ACVRL1, also known as ALK1) as the major gene when PAH is associated with hereditary hemorrhagic telangiectasia. The mutation detection rate for the known genes is approximately 75 in familial PAH, but the mutation shortfall remains unexplained even after careful molecular investigation of these genes. To identify additional genetic variants predisposing to PAH, investigators harnessed the power of next-generation sequencing to successfully identify additional genes that will be described in this report. Furthermore, common genetic predisposing factors for PAH can be identified by genome-wide association studies and are detailed in this paper. The careful study of families and routine genetic diagnosis facilitated natural history studies based on large registries of PAH patients to be set up in different countries. These longitudinal or cross-sectional studies permitted the clinical characterization of PAH in mutation carriers to be accurately described. The availability of molecular genetic diagnosis has opened up a new field for patient care, including genetic counseling for a severe disease, taking into account that the major predisposing gene has a highly variable penetrance between families. Molecular information can be drawn from the genomic study of affected tissues in PAH, in particular, pulmonary vascular tissues and cells, to gain insight into the mechanisms leading to the development of the disease. High-throughput genomic techniques, on the basis of next-generation sequencing, now allow the accurate quantification and analysis of ribonucleic acid, species, including micro-ribonucleic acids, and allow for a genome-wide investigation of epigenetic or regulatory mechanisms, which include deoxyribonucleic acid methylation, histone methylation, and acetylation, or transcription factor binding. © 2013 by the American College of Cardiology Foundation. Published by Elsevier Inc
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