207 research outputs found

    Isomer triggering via nuclear excitation by electron capture

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    Triggering of long-lived nuclear isomeric states via coupling to the atomic shells in the process of nuclear excitation by electron capture (NEEC) is studied. NEEC occurring in highly-charged ions can excite the isomeric state to a triggering level that subsequently decays to the ground state. We present total cross sections for NEEC isomer triggering considering experimentally confirmed low-lying triggering levels and reaction rates based on realistic experimental parameters in ion storage rings. A comparison with other isomer triggering mechanisms shows that, among these, NEEC is the most efficient.Comment: minor changes - updated to the final version; 4 pages, 1 figur

    Coherent control of the cooperative branching ratio for nuclear x-ray pumping

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    Coherent control of nuclear pumping in a three level system driven by x-ray light is investigated. In single nuclei, the pumping performance is determined by the branching ratio of the excited state populated by the x-ray pulse. Our results are based on the observation that in ensembles of nuclei, cooperative excitation and decay leads to a greatly modified nuclear dynamics, which we characterize by a time-dependent cooperative branching ratio. We discuss prospects of steering the x-ray pumping by coherently controlling the cooperative decay. First, we study an ideal case with purely superradiant decay and perfect control of the cooperative emission. A numerical analysis of x-ray pumping in nuclear forward scattering with coherent control of the cooperative decay via externally applied magnetic fields is presented. Next, we provide an extended survey of nuclei suitable for our scheme, and propose proof-of-principle implementations already possible with typical M\"ossbauer nuclear systems such as 57Fe^{57}\mathrm{Fe}. Finally, we discuss the application of such control techniques to the population or depletion of long-lived nuclear states.Comment: 11 pages, 8 figures; updated to the published versio

    Inhibition of Neurogenic Inflammatory Pathways Associated with the Reduction in Discogenic Back Pain

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    STUDY DESIGN: Retrospective cohort study. PURPOSE: This study aimed to determine whether the initiation of anti-calcitonin gene-related peptide (CGRP inhibitor) medication therapy for migraines was also associated with improvements in back/neck pain, mobility, and function in a patient population with comorbid degenerative spinal disease and migraine. OVERVIEW OF LITERATURE: CGRP upregulates pro-inflammatory cytokines such as tumor necrosis factor-α, interleukin-6, brain-derived neurotrophic factor, and nerve growth factor in spinal spondylotic disease, which results in disc degeneration and sensitization of nociceptive neurons. Although CGRP inhibitors can quell neurogenic inflammation in migraines, their off-site efficacy as a therapeutic target for discogenic back/neck pain conditions remains unknown. METHODS: All adult patients diagnosed with spinal spondylosis and migraine treated with CGRP inhibitors at a single academic institution between 2017 and 2020 were retrospectively identified. Patient demographic and medical data, follow-up duration, migraine severity and frequency, spinal pain, functional status, and mobility before and after the administration of CGRP inhibitors were collected. Paired univariate analysis was conducted to determine significant changes in spinal pain, headache severity, and headache frequency before and after the administration of CGRP inhibitors. The correlation between changes in the spinal pain score and functional or mobility improvement was assessed with Spearman\u27s rho. RESULTS: In total, 56 patients were included. The mean follow-up time after the administration of CGRP inhibitors was 123 days for spinal pain visits and 129 days for migraine visits. Back/neck pain decreased significantly (p CONCLUSIONS: Patients taking CGRP inhibitors for chronic migraines with comorbid degenerative spinal conditions experienced significant off-target reduction of back/neck pain

    Perioperative Chanage in Cervical Lordosis and Health-Related Quality-of-Life Outcomes

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    BACKGROUND: Surgeons have scrutinized spinal alignment and its impact on improving clinical outcomes following anterior cervical discectomy and fusion (ACDF). The primary analysis of this study examines the relationship between change in perioperative cervical lordosis (CL) and health-related quality-of-life (HRQOL) outcomes after ACDF. Secondary analysis evaluates the effects of fusion construct length on outcomes in patients grouped by preoperative cervical alignment. METHODS: A retrospective cohort study was performed on an institutional database including patients who underwent 1- to 3-level ACDF. C2-C7 CL was measured preoperatively and at final follow-up. For primary analysis, patients were classified based on their perioperative cervical lordotic correction: (1) kyphotic, (2) maintained, and (3) restored. For secondary analysis, patients were categorized based on their preoperative C2-C7 CL: (1) kyphotic, (2) neutral, and (3) lordotic. Demographics and perioperative change in patient-reported outcome measures were compared between groups. RESULTS: A total of 308 patients were included. A significant difference was noted among maintained, restored, and kyphotic groups in terms of delta physical compositeshort form-12 score (ΔPCS-12) (9.0 vs 10.3 vs 1.5; CONCLUSIONS: Significantly greater PCS-12 and VAS arm improvement were seen in patients whose cervical sagittal alignment was restored to neutral/lordotic compared with those who remained kyphotic. Multivariate analysis demonstrated no association between construct length and perioperative outcomes. CLINICAL RELEVANCE: The results of this study highlight the importance of sagittal alignment and restoration of CL after short-segment ACDF. Irrespective of preoperative sagittal alignment, the length of ACDF fusion construct does not have a significant impact on clinical outcomes

    Inhibition of Neurogenic Inflammatory Pathways Associated with the Reduction in Discogenic Back Pain

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    Study Design Retrospective cohort study. Purpose This study aimed to determine whether the initiation of anti-calcitonin gene-related peptide (CGRP inhibitor) medication therapy for migraines was also associated with improvements in back/neck pain, mobility, and function in a patient population with comorbid degenerative spinal disease and migraine. Overview of Literature CGRP upregulates pro-inflammatory cytokines such as tumor necrosis factor-α, interleukin-6, brain-derived neurotrophic factor, and nerve growth factor in spinal spondylotic disease, which results in disc degeneration and sensitization of nociceptive neurons. Although CGRP inhibitors can quell neurogenic inflammation in migraines, their off-site efficacy as a therapeutic target for discogenic back/neck pain conditions remains unknown. Methods All adult patients diagnosed with spinal spondylosis and migraine treated with CGRP inhibitors at a single academic institution between 2017 and 2020 were retrospectively identified. Patient demographic and medical data, follow-up duration, migraine severity and frequency, spinal pain, functional status, and mobility before and after the administration of CGRP inhibitors were collected. Paired univariate analysis was conducted to determine significant changes in spinal pain, headache severity, and headache frequency before and after the administration of CGRP inhibitors. The correlation between changes in the spinal pain score and functional or mobility improvement was assessed with Spearman’s rho. Results In total, 56 patients were included. The mean follow-up time after the administration of CGRP inhibitors was 123 days for spinal pain visits and 129 days for migraine visits. Back/neck pain decreased significantly (p<0.001) from 6.30 to 4.36 after starting CGRP inhibitor therapy for migraine control. As recorded in the spine follow-up notes, 25% of patients experienced a functional improvement in the activities of daily living, and 17.5% experienced mobility improvement while taking CGRP inhibitors. Change in back/neck pain moderately correlated (ρ=−0.430) with functional improvement but was not correlated with mobility improvement (ρ=−0.052). Conclusions Patients taking CGRP inhibitors for chronic migraines with comorbid degenerative spinal conditions experienced significant off-target reduction of back/neck pain

    Coulomb excitation of a 242Am isomeric target: E2 and e3 strengths, rotational alignment, and collective enhancement

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    A 98% pure242mAm (K = 5-, t1/2 = 141 years) isomeric target was Coulomb excited with a 170.5-MeV 40Ar beam. The selectivity of Coulomb excitation, coupled with the sensitivity of Gammasphere plus CHICO, was sufficient to identify 46 new states up to spin 18h{stroke} in at least four rotational bands; 11 of these new states lie in the isomer band, 13 in a previously unknown yrast Kπ = 6- rotational band, and 13 in a band tentatively identified as the predicted yrast Kπ = 5+ band. The rotational bands based on the Kπ = 5- isomer and the 6-bandhead were populated by Coulomb excitation with unexpectedly equal cross sections. The γ -ray yields are reproduced by Coulomb excitation calculations using a two-particle plus rotor model (PRM), implying nearly complete ΔK = 1 mixing of the two almost-degenerate rotational bands, but recovering the Alaga rule for the unperturbed states. The degeneracy of the 5- and 6- bands allows for precise determination of the mixing interaction strength V, which approaches the strong-mixing limit; this agrees with the 50% attenuation of the Coriolis matrix element assumed in the model calculations. The fractional admixture of the I πK= 6-6 state in the nominal 6-5 isomer band state is measured within the PRM as 45.6+0.3-1.1%. The E2 and M1 strengths coupling the 5- and 6- bands are enhanced significantly by the mixing, while E1 and E2 couplings to other low-K bands are not measurably enhanced. The yields of the 5+ band are reproduced by an E3 strength of ≈15 W.u., competitive with the interband E2 strength. Alignments of the identified two-particle Nilsson states in 242Am are compared with the single-particle alignments in 241Am

    New structures in 178Hf and coulomb excitation of isomers

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    A 985 MeV 178Hf beam was Coulomb excited by a 208Pb target at the ATLAS accelerator of Argonne National Laboratory. Gammasphere and the CHICO particle detector recorded particle-γ coincidence data. The aim was to populate and determine the mechanism of previously observed Coulomb excitation of the Kπ = 6+ (t1/2 = 77 ns), 8- (4 s) and 16+ (31 y) isomer bands. New rotational bands were identified including an aligned band which appears to mix with the ground-state band (GSB) and the γ-vibrational band above ∼ 12 ℏ of angular momentum. Newly observed γ-decay transitions into the three isomer bands may elucidate the K-mixing which allows Coulomb excitation of these isomer bands, but direct decays from the GSB into the 16+ isomer band have not yet been confirmed

    Serotonin Reuptake Inhibitor Increases Pseudarthrosis Rates in Anterior Cervical Discectomy and Fusions

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    STUDY DESIGN: Retrospective cohort. PURPOSE: To determine (1) the effects of serotonin reuptake inhibitors in pseudarthrosis rates after anterior cervical decompression and fusion (ACDF) and (2) to identify patient-reported outcome measures in patients taking serotonin reuptake inhibitors. OVERVIEW OF LITERATURE: Recent literature suggests that selective serotonin reuptake inhibitors (SSRIs) may inhibit fracture healing via downregulation of osteoblast differentiation. Spinal fusion supplementation with osteoblast-rich substances enhances spinal fusion, thus SSRIs may be detrimental. METHODS: Patients with 1-year postoperative dynamic cervical spine radiographs following ACDF were grouped into serotonin reuptake inhibitor prescriptions (SSRI, serotonin-norepinephrine reuptake inhibitor [SNRI], or tricyclic antidepressant [TCA]) and no prescription (atypical antidepressant or no antidepressant). Pseudarthrosis was defined as ≥1 mm interspinous process motion on dynamic radiographs. Logistic regression models were controlled for confounding to analyze pseudarthrosis rates. Alpha was set at p - values of \u3c0.05. RESULTS: Of the 523 patients who meet the inclusion criteria, 137 (26.2%) were prescribed an SSRI, SNRI, or TCA. Patients with these prescriptions were more likely to have pseudarthrosis (p =0.008) but not a revision surgery due to pseudarthrosis (p =0.219). Additionally, these patients had worse 1-year postoperative mental component summary (MCS)-12 (p =0.015) and Neck Disability Index (NDI) (p =0.006). The multivariate logistic regression analysis identified SSRI/SNRI/TCA use (odds ratio [OR], 1.82; 95% confidence interval [CI], 1.11-2.99; p =0.018) and construct length (OR, 1.91; 95% CI, 1.50-2.44; p CONCLUSIONS: Patients taking serotonin reuptake-inhibiting antidepressants are at increased risk of worse postoperative outcome scores, including NDI and MCS-12, likely due to their underlying depression. This may contribute to their greater likelihood of having adjacent segment surgery. Additionally, preoperative use of serotonin reuptake inhibitors in patients undergoing an ACDF is a predictor of radiographic pseudarthrosis but not pseudarthrosis revision

    Honey, a Gift from Nature to Health and Beauty: A Review

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    Benefits of honey are contributed by the composition of its elements such as glucose, fructose, glucose oxidase, vitamins and phenolic compounds. For health, honey can be used to treat wounds due to the antibacterial activity conferred by the hydrogen peroxide produced by glucose oxidase in honey. Anti-inflammatory, anti-oxidant, deodorizing and tissue regeneration activities in honey also help in the wound healing process. It can also be an alternative sweetener for diabetic patients to ensure compliance to a healthy diet. Moreover, honey exerts several effects such as lowering low density lipids and increasing high density lipids, thus reducing risk of atherosclerosis. In terms of beauty, honey can be used on skin and hair. It moisturizes skin through its natural humectant properties contributed by high contents of fructose and glucose. Honey treats acne on the skin due to its antibacterial activity, anti-inflammatory action and tissue repair. The hair can benefit from honey in such a way that the hair has abundance, and becomes easier to comb. However, there have not been as many studies regarding the use of honey in skin in comparison to its use for health. Therefore, future studies on honey could research its use, action and benefits in both cosmetics and dermatology
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