Identification Thresholds of the Human Visual System for an Alphanumeric Resolution Test Object

Many investigations of the detection threshold of the human visual system have been conducted, and a few recognition threshold studies can be found, however no identification threshold data are available. This paper documents research on the observer\u27s identification threshold for an alphanumeric resolution test object presented at various average luminance levels, contrasts, and contrast polarities. These factors affected the identification threshold in a similar way to the effects they exert on the observer\u27s detection and recognition thresholds; the test object contrast being the most significant factor. Direct numerical comparisons between the various thresholds were not possible due to the large inherent differences between the test object visual task complexities found in the many threshold investigations

Baseline representativeness of patients in clinics enrolled in the PRimary care Opioid Use Disorders treatment (PROUD) trial: comparison of trial and non-trial clinics in the same health systems

BACKGROUND: Pragmatic primary care trials aim to test interventions in real world health care settings, but clinics willing and able to participate in trials may not be representative of typical clinics. This analysis compared patients in participating and non-participating clinics from the same health systems at baseline in the PRimary care Opioid Use Disorders treatment (PROUD) trial. METHODS: This observational analysis relied on secondary electronic health record and administrative claims data in 5 of 6 health systems in the PROUD trial. The sample included patients 16-90 years at an eligible primary care visit in the 3 years before randomization. Each system contributed 2 randomized PROUD trial clinics and 4 similarly sized non-trial clinics. We summarized patient characteristics in trial and non-trial clinics in the 2 years before randomization ( baseline ). Using mixed-effect regression models, we compared trial and non-trial clinics on a baseline measure of the primary trial outcome (clinic-level patient-years of opioid use disorder (OUD) treatment, scaled per 10,000 primary care patients seen) and a baseline measure of the secondary trial outcome (patient-level days of acute care utilization among patients with OUD). RESULTS: Patients were generally similar between the 10 trial clinics (n = 248,436) and 20 non-trial clinics (n = 341,130), although trial clinics\u27 patients were slightly younger, more likely to be Hispanic/Latinx, less likely to be white, more likely to have Medicaid/subsidized insurance, and lived in less wealthy neighborhoods. Baseline outcomes did not differ between trial and non-trial clinics: trial clinics had 1.0 more patient-year of OUD treatment per 10,000 patients (95% CI: - 2.9, 5.0) and a 4% higher rate of days of acute care utilization than non-trial clinics (rate ratio: 1.04; 95% CI: 0.76, 1.42). CONCLUSIONS: trial clinics and non-trial clinics were similar regarding most measured patient characteristics, and no differences were observed in baseline measures of trial primary and secondary outcomes. These findings suggest trial clinics were representative of comparably sized clinics within the same health systems. Although results do not reflect generalizability more broadly, this study illustrates an approach to assess representativeness of clinics in future pragmatic primary care trials

Single-crystal diamond pixelated radiation detector with buried graphitic electrodes

A new type of transmissive pixel detector has been developed for synchrotron radiation diagnostics at Diamond Light Source. A thin single-crystal CVD diamond plate is used as the detector material, and a pulsed-laser technique has been used to write conductive graphitic electrodes inside the diamond plate. Instead of using traditional electrodes formed from a layer of surface metallisation, the graphitic electrodes are buried under the surface of the diamond and result in an all-carbon imaging detector. Within the instrument’s transmissive aperture there are no surface structures that could be damaged by exposure to radiation beams, and no surface metallization that could introduce unwanted absorption edges. The instrument has successfully been used to image the X-ray beam profile and measure the beam position to sub-micron accuracy at 100 Hz at Diamond Light Source. A novel modulation lock-in technique is used to read out all pixels simultaneously. Presented in this work are measurements of the detector’s beam position resolution and intensity resolution. Initial measurements of the instrument’s spread-function are also presented. Numerical simulations are used to identify potential improvements to the electrode geometry to improve the spatial resolution of similar future detectors. The instrument has applications in both synchrotron radiation instrumentation, where real-time monitoring of the beam profile is useful for beam diagnostics and fault-finding, and particle tracking at colliders, where the electrode geometries that buried graphitic tracks can provide increased the charge collection efficiency of the detector

Late Quaternary Tectonics, Northern End of Juan de Fuca Ridge (Northeast Pacific)

Office of Naval Research. Contract Nonr-477-(37) and N-00014-67-A-0103-001

Graffiti: A framework for testing collaborative distributed metadata

The growth in metadata has been triggered by two key catalyzing events. The first is the explosive growth in storage size and storage demands. As the number and variety of files grows the need for metadata to organize this informatio

LiFS: An attribute-rich file system for storage class memories

As the number and variety of files stored and accessed by a typical user has dramatically increased, existing file system structures have begun to fail as a mechanism for managing all of the information contained in those files. Many applications—email clients, multimedia management applications, and desktop search engines are examples—have been forced to develop their own richer metadata infrastructures. While effective, these solutions are generally non-standard, non-portable, non-sharable across applications, users or platforms, proprietary, and potentially inefficient. In the interest of providing a rich, efficient, shared file system metadata infrastructure, we have developed the Linking File System (LiFS). Taking advantage of nonvolatile storage class memories, LiFS supports a wide variety of user and application metadata needs while efficiently supporting traditional file system operations. 1

Abstract LiFS: An Attribute-Rich File System for Storage Class Memories

As the number and variety of files stored and accessed by a typical user has dramatically increased, existing file system structures have begun to fail as a mechanism for managing all of the information contained in those files. Many applications—email clients, multimedia management applications, and desktop search engines are examples— have been forced to develop their own richer metadata infrastructures. While effective, these solutions are generally non-standard, non-portable, non-sharable across applications, users or platforms, proprietary, and potentially inefficient. In the interest of providing a rich, efficient, shared file system metadata infrastructure, we have developed the Linking File System (LiFS). Taking advantage of non-volatile storage class memories, LiFS supports a wide variety of user and application metadata needs while efficiently supporting traditional file system operations.

Rapid induction of functional and morphological continuity between severed ends of mammalian or earthworm myelinated axons

The inability to rapidly restore the loss of function that results from severance (cutting or crushing) of PNS and CNS axons is a severe clinical problem. As a novel strategy to help alleviate this problem, we have developed in vitro procedures using Ca21-free solutions of polyethylene glycol (PEG solutions), which within minutes induce functional and morphological continuity (PEG-induced fusion) between the cut or crushed ends of myelinated sciatic or spinal axons in rats. Using a PEG-based hydrogel that binds to connective tissue to provide mechanical strength at the lesion site and is nontoxic to nerve tissues in earthworms and mammals, we have also developed in vivo procedures that permanently maintain earthworm myelinated medial giant axons whose functional and morphological integrity has been restored by PEG-induced fusion after axonal severance. In all these in vitro or in vivo procedures, the success of PEG-induced fusion of sciatic or spinal axons and myelinated medial giant axons is measured by the restored conduction of action potentials through the lesion site, the presence of intact axonal profiles in electron micrographs taken at the lesion site, and/or the intra-axonal diffusion of fluorescent dyes across the lesion site. These and other data suggest that the application of polymeric fusiogens (such as our PEG solutions), possibly combined with a tissue adherent (such as our PEG hydrogels), could lead to in vivo treatments that rapidly and permanently repair cut or crushed axons in the PNS and CNS of adult mammals, including humans.These studies were funded by National Institutes of Health Grants NS31256 and HD31484, a Texas Advanced Technology grant to G.D.B., personal funds of G.D.B., and National Science Foundation Grant BES-9696020 to J.A.H.Neuroscienc

Rapid induction of functional and morphological continuity between severed ends of mammalian or earthworm myelinated axons

The inability to rapidly restore the loss of function that results from severance (cutting or crushing) of PNS and CNS axons is a severe clinical problem. As a novel strategy to help alleviate this problem, we have developed in vitro procedures using Ca21-free solutions of polyethylene glycol (PEG solutions), which within minutes induce functional and morphological continuity (PEG-induced fusion) between the cut or crushed ends of myelinated sciatic or spinal axons in rats. Using a PEG-based hydrogel that binds to connective tissue to provide mechanical strength at the lesion site and is nontoxic to nerve tissues in earthworms and mammals, we have also developed in vivo procedures that permanently maintain earthworm myelinated medial giant axons whose functional and morphological integrity has been restored by PEG-induced fusion after axonal severance. In all these in vitro or in vivo procedures, the success of PEG-induced fusion of sciatic or spinal axons and myelinated medial giant axons is measured by the restored conduction of action potentials through the lesion site, the presence of intact axonal profiles in electron micrographs taken at the lesion site, and/or the intra-axonal diffusion of fluorescent dyes across the lesion site. These and other data suggest that the application of polymeric fusiogens (such as our PEG solutions), possibly combined with a tissue adherent (such as our PEG hydrogels), could lead to in vivo treatments that rapidly and permanently repair cut or crushed axons in the PNS and CNS of adult mammals, including humans.These studies were funded by National Institutes of Health Grants NS31256 and HD31484, a Texas Advanced Technology grant to G.D.B., personal funds of G.D.B., and National Science Foundation Grant BES-9696020 to J.A.H.Neuroscienc