Radio Signatures of HI at High Redshift: Mapping the End of the ``Dark Ages''

The emission of 21-cm radiation from a neutral intergalactic medium (IGM) at high redshift is discussed in connection with the thermal and ionization history of the universe. The physical mechanisms that make such radiation detectable against the cosmic microwave background include Ly_alpha coupling of the hydrogen spin temperature to the kinetic temperature of the gas and preheating of the IGM by the first generation of stars and quasars. Three different signatures are investigated in detail: (a) the fluctuations in the redshifted 21-cm emission induced by the gas density inhomogeneities that develop at early times in cold dark matter (CDM) dominated cosmologies; (b) the sharp absorption feature in the radio sky due to the rapid rise of the Ly_alpha continuum background that marks the birth of the first UV sources in the universe; and (c) the 21-cm emission and absorption shells that are generated on several Mpc scales around the first bright quasars. Future radio observations with projected facilities like the Giant Metrewave Radio Telescope and the Square Kilometer Array may shed light on the power spectrum of density fluctuations at z>5, and map the end of the "dark ages", i.e. the transition from the post-recombination universe to one populated with radiation sources.Comment: LateX, 19 pages, 5 figures, significantly revised version to be published in the Ap

Clinical Effects of Electromagnetic Stimulation as an Adjunct to Periodontal Therapy

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141604/1/jper0046.pd

A core Outcome Set for Seamless, Standardized Evaluation of Innovative Surgical Procedures and Devices (COHESIVE)

OBJECTIVE: To develop a core outcome set (COS), an agreed minimum set of outcomes to measure and report in all studies evaluating the introduction and evaluation of novel surgical techniques. SUMMARY BACKGROUND DATA: Agreement on the key outcomes to measure and report for safe and efficient surgical innovation is lacking, hindering transparency and risking patient harm. METHODS: Agreement on the key outcomes to measure and report for safe and efficient surgical innovation is lacking, hindering transparency and risking patient harm. RESULTS: 7,972 verbatim outcomes were identified, categorized into 32 domains, and formatted into survey items/questions. 410 international participants (220 professionals, 190 patients/public) completed at least one round 1 survey item, of which 153 (69.5%) professionals and 116 (61.1%) patients completed at least one round 2 item. 12 outcomes were scored ‘consensus in’ (‘very important’ by ≥70% of patients and professionals) and 20 ‘no consensus’. A consensus meeting, involving 19 professionals and 10 patient/public representatives, led to agreement on a final 8-domain COS. Six domains are specific to a surgical innovation context: modifications, unexpected disadvantages, device problems, technical procedure success, whether the overall desired effect was achieved, surgeons’/operators’ experience. Two domains relate to intended benefits and expected disadvantages. CONCLUSIONS: The COS is recommended for use in all studies prior to definitive RCT evaluation to promote safe, transparent, and efficient surgical innovation

Dynamic Balance In Children: Performance Comparison Between Two Testing Devices

Please view abstract in the attached PDF file

Outcome selection, measurement and reporting for new surgical procedures and devices:a systematic review of IDEAL/IDEAL-D studies to inform development of a core outcome set

BackgroundOutcome selection, measurement and reporting for the evaluation of new surgical procedures and devices is inconsistent and lacks standardization. A core outcome set may promote the safe and transparent evaluation of surgical innovations. This systematic review examined outcome selection, measurement and reporting in studies conducted within the IDEAL (Idea, Development, Exploration, Assessment and Long‐term monitoring) framework to examine current practice and inform the development of a core outcome set for early‐phase studies of surgical procedures/devices.MethodsWeb of Science and Scopus citation searches were performed to identify author‐reported IDEAL/IDEAL‐D studies for any surgical procedure/device. Outcomes were extracted verbatim, including contextual information regarding outcome selection and measurement. Outcomes were categorized to inform a conceptual framework of outcome domains relevant to evaluating innovation.ResultsSome 48 studies were identified. Outcome selection, measurement and reporting varied widely across studies in different IDEAL stages. From 1737 outcomes extracted, 22 domains specific to evaluating innovation were conceptualized under seven broad categories: procedure completion success/failure; modifications; unanticipated events; surgeons' experiences; patients' experiences; resource use specific to the innovative procedure/device; and other innovation‐specific outcomes. Most innovation‐specific outcomes were measured and reported in only a small number of studies.ConclusionThis review highlighted the need for guidance and standardization in outcome selection and reporting in the evaluation of new surgical procedures/devices. Novel outcome domains specific to innovation have been identified to establish a core outcome set for future evaluations of surgical innovations

Phenomenological Study of Strong Decays of Heavy Hadrons in Heavy Quark Effective Theory

The application of the tensor formalism of the heavy quark effective theory (HQET) at leading order to strong decays of heavy hadrons is presented. Comparisons between experimental and theoretical predictions of ratios of decay rates for B mesons, D mesons and kaons are given. The application of HQET to strange mesons presents some encouraging results. The spin-flavor symmetry is used to predict some decay rates that have not yet been measured.Comment: 10 page

Reactive nitrogen in Asian continental outflow over the western Pacific: Results from the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) airborne mission

We present here results for reactive nitrogen species measured aboard the NASA DC-8 aircraft during the Transport and Chemical Evolution over the Pacific (TRACE-P) mission. The large-scale distributions total reactive nitrogen (NOy,sum = NO + NO2 + HNO3 + PAN + C1–C5alkyl nitrates) and O3 and CO were better defined in the boundary layer with significant degradation of the relationships as altitude increased. Typically, NOy,sum was enhanced over background levels of ∼260 pptv by 20-to-30-fold. The ratio C2H2/CO had values of 1–4 at altitudes up to 10 km and as far eastward as 150°E, implying significant vertical mixing of air parcels followed by rapid advection across the Pacific. Analysis air parcels originating from five principal Asian source regions showed that HNO3 and PAN dominated NOy,sum. Correlations of NOy,sum with C2Cl4 (urban tracer) were not well defined in any of the source regions, and they were only slightly better with CH3Cl (biomass tracer). Air parcels over the western Pacific contained a complex mixture of emission sources that are not easily resolvable as shown by analysis of the Shanghai mega-city plume. It contained an intricate mixture of pollution emissions and exhibited the highest mixing ratios of NOy,sum species observed during TRACE-P. Comparison of tropospheric chemistry between the earlier PEM-West B mission and the recent TRACE-P data showed that in the boundary layer significant increases in the mixing ratios of NOy,sum species have occurred, but the middle and upper troposphere seems to have been affected minimally by increasing emissions on the Asian continent over the last 7 years