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Purpose: To evaluate the effect of interocular axial length (AL) difference on outcomes of treatment for anisometropic amblyopia in comparison with normal participants. Methods: In this historical cohort study, 83 patients with anisometropic amblyopia were divided into two age groups, 70 children (mean, 7.86 ± 1.56 and range, 5–15 years) and 13 adults (mean, 26.46 ± 10.87 and range, 16–45 years). The control group consisted of 43 non-amblyopic children and 17 non-amblyopic adults. Treatment outcomes after a period of one year were defined as successful or unsuccessful when posttreatment amblyopic corrected distance visual acuity (CDVA) was reported as ≤0.9 versus CDVA ≤ 0.8, respectively. AL was measured using a Lenstar LS900 (Haag-Streit AG, Switzerland). Results: Fifty-nine patients showed satisfactory treatment outcomes (55 children and 4 adults), while unsuccessful treatment outcomes were observed in 24 patients (15 children and 9 adults). The mean of amblyopia treatment duration was 1.24 ± 0.76 years. The mean of interocular AL difference in all patients, control, successful and unsuccessful treatment outcome groups were 0.49 ± 0.70mm (range, 0.00–3.89 mm), 0.12 ± 0.07 mm (range, 0.02–0.41), 0.33 ± 0.23 mm (range, 0.00–0.99 mm), and 1.81 ± 0.80 mm (range, 1.14–3.89 mm), respectively. In both age groups, the mean of interocular AL difference in patients with unsuccessful treatment outcomes was greater than those with successful treatment outcomes and that of the control group (P < 0.001). Conclusion: The results of this study suggest that the outcome of anisometropic amblyopia treatment may depend on the interocular AL difference.

Dynamic Nuclear Polarization (DNP) is a powerful suite of techniques that deliver multifold signal enhancements in NMR and MRI. The generated athermal spin states can also be exploited for quantum sensing and as probes for many-body physics. Typical DNP methods require use of cryogens, large magnetic fields, and high power microwaves, which are expensive and unwieldy. Nanodiamond particles, rich in Nitrogen-Vacancy (NV) centers, have attracted attention as alternative DNP agents because they can potentially be optically hyperpolarized at room temperature. Indeed the realization of a miniature "optical nanodiamond hyperpolarizer", where 13C nuclei are optically hyperpolarized has been a longstanding goal but has been technically challenging to achieve. Here, unravelling new physics underlying an optical DNP mechanism first introduced in [Ajoy et al., Sci. Adv. 4, eaar5492 (2018)], we report the realization of such a device in an ultracompact footprint and working fully at room temperature. Instrumental requirements are very modest: low polarizing fields, extremely low optical and microwave irradiation powers, and convenient frequency ranges that enable device miniaturization. We obtain best reported optical 13C hyperpolarization in diamond particles exceeding 720 times of the thermal 7T value (0.86% bulk polarization), corresponding to a ten-million-fold gain in NMR averaging time. In addition the hyperpolarization signal can be background-suppressed by over two-orders of magnitude and retained for multiple-minute long periods. Besides compelling applications in quantum sensing, and bright-contrast MRI imaging, this work paves the way for low-cost DNP platforms that relay the 13C polarization to liquids in contact with the high surface-area particles. This will ultimately allow development of miniature "quantum-assisted" NMR spectrometers for chemical analysis., Contains supplementary info

The origins of spin lifetimes in quantum systems is a matter of importance in several areas of quantum information. Spectrally mapping spin relaxation processes provides insight into their origin and motivates methods to mitigate them. In this paper, we map nuclear relaxation in a prototypical system of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${}^{13}{\rm{C}}$$\end{document}13C nuclei in diamond coupled to Nitrogen Vacancy (NV) centers over a wide field range (1 mT-7 T). Nuclear hyperpolarization through optically pumped NV electrons allows signal measurement savings exceeding million-fold over conventional methods. Through a systematic study with varying substitutional electron (P1 center) and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${}^{13}{\rm{C}}$$\end{document}13C concentrations, we identify the operational relaxation channels for the nuclei at different fields as well as the dominant role played by \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${}^{13}{\rm{C}}$$\end{document}13C coupling to the interacting P1 electronic spin bath. These results motivate quantum control techniques for dissipation engineering to boost spin lifetimes in diamond, with applications including engineered quantum memories and hyperpolarized \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${}^{13}{\rm{C}}$$\end{document}13C imaging., Nuclear spins in diamond have applications in quantum technologies and NMR methods but their performance can be limited by relaxation processes that are difficult to characterise. Ajoy et al. develop a T1 noise spectroscopy method to identify the dominant relaxation channel and propose a mitigation strategy.

We describe the construction of a fast field cycling device capable of sweeping a 4-order-of-magnitude range of magnetic fields, from ∼1 mT to 7 T, in under 700 ms, and which is further extendable to a 1 nT-7 T range. Central to this system is a high-speed sample shuttling mechanism between a superconducting magnet and a magnetic shield, with the capability to access arbitrary fields in between with high resolution. Our instrument serves as a versatile platform to harness the inherent dichotomy of spin dynamics on offer at low and high fields-in particular, the low anisotropy, fast spin manipulation, and rapid entanglement growth at low field as well as the long spin lifetimes, spin specific control, and efficient inductive measurement possible at high fields. Exploiting these complementary capabilities in a single device opens up applications in a host of problems in quantum control, sensing, and information storage, besides in nuclear hyperpolarization, relaxometry, and imaging. In particular, in this paper, we focus on the ability of the device to enable low-field hyperpolarization of 13C nuclei in diamond via optically pumped electronic spins associated with nitrogen vacancy defect centers. ispartof: REVIEW OF SCIENTIFIC INSTRUMENTS vol:90 issue:1 ispartof: location:United States status: published

© 2018 The Authors, some rights reserved. Dynamic nuclear polarization via contact with electronic spins has emerged as an attractive route to enhance the sensitivity of nuclear magnetic resonance beyond the traditional limits imposed by magnetic field strength and temperature. Among the various alternative implementations, the use of nitrogen vacancy (NV) centers in diamond-a paramagnetic point defect whose spin can be optically polarized at room temperature-has attracted widespread attention, but applications have been hampered by the need to align the NV axis with the external magnetic field. We overcome this hurdle through the combined use of continuous optical illumination and a microwave sweep over a broad frequency range. As a proof of principle, we demonstrate our approach using powdered diamond with which we attain bulk13C spin polarization in excess of 0.25% under ambient conditions. Remarkably, our technique acts efficiently on diamond crystals of all orientations and polarizes nuclear spins with a sign that depends exclusively on the direction of the microwave sweep. Our work paves the way toward the use of hyperpolarized diamond particles as imaging contrast agents for biosensing and, ultimately, for the hyperpolarization of nuclear spins in arbitrary liquids brought in contact with their surface.

Dynamic Nuclear Polarization (DNP) has enabled enormous gains in magnetic resonance signals and led to vastly accelerated NMR/MRI imaging and spectroscopy. Unlike conventional cw-techniques, DNP methods that exploit the full electron spectrum are appealing since they allow direct participation of all electrons in the hyperpolarization process. Such methods typically entail sweeps of microwave radiation over the broad electron linewidth to excite DNP, but are often inefficient because the sweeps, constrained by adiabaticity requirements, are slow. In this paper we develop a technique to overcome the DNP bottlenecks set by the slow sweeps, employing a swept microwave frequency comb that increases the effective number of polarization transfer events while respecting adiabaticity constraints. This allows a multiplicative gain in DNP enhancement, scaling with the number of comb frequencies and limited only by the hyperfine-mediated electron linewidth. We demonstrate the technique for the optical hyperpolarization of 13C nuclei in powdered microdiamonds at low fields, increasing the DNP enhancement from 30 to 100 measured with respect to the thermal signal at 7T. For low concentrations of broad linewidth electron radicals, e.g. TEMPO, these multiplicative gains could exceed an order of magnitude., Comment: Contains supplementary info

Given the increasing growth of technology especially in information technology and the existence of some obstacles such as geographical distribution, restrictions on the provision of resources and cost, researchers need an infrastructure to they can implement all the research related issues from idea to implementation and testing. The paper intends to introduce the appropriate platforms for solving these problems based on using cloud computing. Cloud computing is changing higher education and academic researchers to manage research faster and more cost-effectively than ever before. Cloud also provides real-time access to a broad set of tools, languages, and frameworks and direct access to virtually unlimited computing resources. Some cloud platforms such as AWS and Microsoft Azure provide research service along with business activities but some others are purely research. Introducing the services of each these environments and comparing between them base on unique comparative parameters such as VM migration support, custom image support, image library, auto-scaling, network connectivity, storage choices, regional support and virtualization software hypervisor, express the goal of this paper.

Shining light on diamond particles makes them MRI-“bright,” opening avenues for room temperature hyperpolarized liquids., Dynamic nuclear polarization via contact with electronic spins has emerged as an attractive route to enhance the sensitivity of nuclear magnetic resonance beyond the traditional limits imposed by magnetic field strength and temperature. Among the various alternative implementations, the use of nitrogen vacancy (NV) centers in diamond—a paramagnetic point defect whose spin can be optically polarized at room temperature—has attracted widespread attention, but applications have been hampered by the need to align the NV axis with the external magnetic field. We overcome this hurdle through the combined use of continuous optical illumination and a microwave sweep over a broad frequency range. As a proof of principle, we demonstrate our approach using powdered diamond with which we attain bulk 13C spin polarization in excess of 0.25% under ambient conditions. Remarkably, our technique acts efficiently on diamond crystals of all orientations and polarizes nuclear spins with a sign that depends exclusively on the direction of the microwave sweep. Our work paves the way toward the use of hyperpolarized diamond particles as imaging contrast agents for biosensing and, ultimately, for the hyperpolarization of nuclear spins in arbitrary liquids brought in contact with their surface.

Dendritic cells are important in initiating immune responses; therefore, a range of dendritic cell–based approaches have been established to induce immune response against cancer cells. However, the presence of immunosuppressive mediators such as adenosine in the tumor microenvironment reduces the efficacy of dendritic cell–based cancer immunotherapy. In this study, we investigated whether blockade of the A2A adenosine receptor with a selective antagonist and a CD73 inhibitor may increase the efficacy of a dendritic cell–based cancer vaccine. According to the findings, this therapeutic combination reduced tumor growth, prolonged survival of tumor-bearing mice, and enhanced specific antitumor immune responses. Thus, we suggest that targeting cancer-derived adenosine improves the outcomes of dendritic cell–based cancer immunotherapy.

This project focused on the mechanisms of hypoxic induction of neovascularisation in human cornea and identification of the angiogenic molecules produced into the precorneal tear film when the level of oxygen reaching the cornea was less than optimal. Mediators of neovascularisation selected from literature were studied in the supernatants from hypoxic HCE cultures using ELISA and a multiplex bead assay. HIF-la, angiogenin and VEGF were upregulated, IL-8, lL-6 and nitric oxide showed reduction; while some of the interleukins and growth factors, erythropoietin and 12(S)-HETE (a product of the lipoxygenase pathway of arachidonic acid metabolism) were below detection level. Hypoxic samples were subsequently applied to a cell line representing microvascular endothelial cells (HMEC-l). Microvascular endothelial cells consistently showed increased migration and tube formation but not proliferation and paracellular permeability when incubated in HCE supernatants collected from 0% oxygen experiments (48 hours and 72 hours incubations of HCE in 0% oxygen). Inhibition of individual mediators of angiogenesis and metabolic pathways of arachidonic acid suggested involvement of VEGF along with Cycloxygenase and 12-LOX pathways in mediation of the migratory response. Angiogenin seemed to play an inhibitory role in the migration and an enhancing role in proliferation of the HMEC-l cells at concentrations similar to those found in hypoxic HCE media. EGF and PDGF seemed to be not involved in the corneal epithelial response to hypoxia. To validate in vitro results tear content of VEGF, angiogenin, 12(S)-HETE and erythropoietin were compared in a pilot clinical study. Closed eye tears and open eye tears were collected before and after 24 hours of high oxygen and low oxygen permeability contact lens wear. VEGF, 12(S)-HETE and angiogenin showed very high levels of expression both in open eye and closed eye tears. The concentration of angiogenin was higher in closed eye tears in the no lens wear group and low oxygen permeability contact lens wear group (Etafilcon A contact lenses). Paradoxically, VEGF levels drainatically increased during overnight wear of the high oxygen permeability lens. These experiments need to be repeated in larger sample groups. Taken together, these studies indicate that corneal epithelium is capable of initiating hypoxic angiogenic response, possibly through expression of VEGF, angiogenin and 12(S)-HETE.

To apply the Behavioral Model for Vulnerable Populations to the examination of the correlates of alternative healthcare utilization among Hispanic and African-American adults residing in public housing.Cross-sectional survey of a community-based sample.Urban public housing communities in the county of Los Angeles.A geographically defined random sample of 287 African-American and Latino heads of households from three urban public housing communities.The use of alternative health care was assessed with three indices reflecting how frequently respondents used alternative sources of health care: 1) to prevent sickness; 2) to treat sickness; and 3) to substitute for conventional health care. Multivariate analysis of data indicates that lower education, greater perceived racial discrimination, and poorer health status were associated with the use of alternative health care to prevent sickness. Furthermore, greater perceived racial discrimination, greater financial strain, and poorer health status were associated with the use of alternative health care to treat sickness. In addition, four variables were associated with increased frequency of alternative healthcare utilization as a substitute for conventional care, namely: 1) diminished belief that powerful individuals (such as healthcare professionals) control one's health; 2) greater perception of racial discrimination; 3) greater financial strain; and 4) reduced access to health care.Enabling characteristics helped explain the use of alternative health care to treat sickness as a substitute for conventional health care, but not to prevent sickness, in this population. Perceived racial discrimination was the strongest correlate for each type of alternative healthcare use, while health status was also a strong predictor. The use of alternative health care for prevention and for substitution should be examined separately in disadvantaged minority populations.

To determine the comparative efficacy of Exosurf Neonatal and Survanta surfactants on the early course of respiratory distress syndrome (RDS), arterial blood gases, ventilatory support, outcome morbidity rate, and complications of prematurity and RDS.Medical records from 203 premature newborn infants undergoing mechanical ventilation for respiratory distress syndrome, and who received up to four rescue doses of either Exosurf or Survanta, were retrospectively reviewed.All groups were comparable for birth weight and gestational age. Although the two randomized groups were similar in severity of RDS based on fraction of inspired oxygen (FIO2) and ventilatory support, a significantly greater improvement in respiratory function as evidenced by FIO2, mean airway pressure, alveolar-arterial partial pressure of oxygen difference, and oxygen index, was observed in the Survanta group from 12 hours (p0.05) through 48 hours (p0.01). Comparison of outcome morbidity rate by gestational age showed a higher occurrence of retinopathy of prematurity (p0.02) among the older infants (28 to 32 weeks) who were treated with Exosurf.Survanta exerted a significantly faster response in the early clinical course of RDS compared with Exosurf. However, no difference in the impact on eventual respiratory outcome was observed. We therefore conclude that both surfactants are effective for the treatment of RDS.