314 results on '"John P. Greene"'
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2. Anakinra or high-dose corticosteroids in COVID-19 pneumonia patients who deteriorate on low-dose dexamethasone: an observational study of comparative effectiveness
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Annette Langer-Gould, Stanley Xu, Laura C. Myers, Aiyu Chen, John D. Greene, Beth Creekmur, Katia Bruxvoort, John L. Adams, Vincent Liu, and Michael K. Gould
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Corticosteroids ,Anakinra ,COVID-19 ,Mortality ,Infections ,Infectious and parasitic diseases ,RC109-216 - Abstract
Objectives: To assess whether escalating to high-dose corticosteroids or anakinra compared with continuing low-dose corticosteroids reduced mortality in patients with severe COVID-19 whose respiratory function deteriorated while receiving dexamethasone 6 mg daily. Methods: We conducted a retrospective cohort study between March 1 to December 31, 2020, of hospitalized patients with confirmed COVID-19 pneumonia. In-hospital death was analyzed using logistic regression with inverse probability of treatment weighting of receiving anakinra, high-dose corticosteroid (dexamethasone >10 mg daily), or remaining on low-dose corticosteroids on the day of first respiratory deterioration. Results: We analyzed 6671 patients whose respiratory status deteriorated while receiving dexamethasone 6 mg daily for COVID-19 pneumonia, of whom 6265 stayed on low-dose corticosteroids, 232 were escalated to high-dose corticosteroids, and 174 to anakinra in addition to corticosteroids. The propensity score-adjusted odds of death were higher in the anakinra (odds ratio [OR] 1.76; 95% CI 1.13-2.72) and high-dose corticosteroid groups (OR 1.53; 95% CI 1.14-2.07) compared with those who continued low-dose corticosteroids on the day of respiratory deterioration. The odds of hospital-acquired infections were also higher in the anakinra (OR 2.00; 95% CI 1.28-3.11) and high-dose corticosteroid groups (OR 1.43; 95% CI 1.00-2.04) compared with low-dose corticosteroid group. Conclusion: Our findings do not support escalating patients with COVID-19 pneumonia who deteriorate on low-dose corticosteroids to high-dose corticosteroids or anakinra.
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- 2023
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3. High-dose corticosteroids in patients hospitalized for COVID-19 pneumonia: an observational study of comparative effectiveness
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Annette Langer-Gould, Stanley Xu, Laura C. Myers, Aiyu Chen, John D. Greene, Beth Creekmur, Katia Bruxvoort, John L. Adams, Vincent Liu, and Michael K. Gould
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Corticosteroids ,Anakinra ,COVID-19 ,Mortality ,Infections ,Infectious and parasitic diseases ,RC109-216 - Abstract
Objectives: To assess whether high- compared with low-dose corticosteroids started upon hospitalization reduce mortality in patients with severe COVID-19 pneumonia or in subgroups stratified by severity of respiratory impairment on admission. Methods: We conducted a retrospective cohort study of patients with confirmed SARS-CoV-2 infection who required oxygen supplementation upon hospitalization between March 1 and December 31, 2020. In-hospital death was analyzed using logistic regression with inverse probability of treatment weighting of receiving low- or high-dose corticosteroid (dexamethasone 6-10 mg daily or >10-20 mg daily or other corticosteroid equivalents). Results: We analyzed 13,366 patients who received low-dose and 948 who received high-dose corticosteroids, of whom 31.3% and 40.4% had severe respiratory impairment (>15 l/min of oxygen or mechanical ventilation) upon admission, respectively. There were no differences in the propensity score-adjusted odds of death (odds ratio 1.17, 95% CI 0.72-1.90) or infections (odds ratio 0.70, 95% CI 0.44-1.11) for patients who received high-dose compared with low-dose corticosteroids, beginning on the day of admission. No significant differences in subgroups stratified by severity of respiratory impairment were found. Conclusion: Initiating high-dose compared with low-dose corticosteroids among newly hospitalized patients with COVID-19 pneumonia did not improve survival. However, benefit of high-dose corticosteroids in specific subgroups cannot be excluded.
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- 2022
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4. Multidisciplinary approach in diagnosis and treatment of COVID-19-associated mucormycosis: a description of current reports
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Hyma Gogineni, Wonhee So, Kenneth Mata, and John N. Greene
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COVID-19 ,Mucormycosis ,Multidisciplinary team ,CAM ,Internal medicine ,RC31-1245 - Abstract
Abstract Background We reviewed the epidemiology, risk factors, pathophysiology, and clinical presentations of coronavirus disease 2019 (COVID-19)-associated mucormycosis (CAM), then discussed the importance of rapid diagnosis and treatment facilitated by multidisciplinary approach. Main body India has reported world’s highest number of CAM cases where Rhizopus arrhizus was the most predominant etiology. CAM caused by Rhizopus microsporus was the most common from the rest of the world. Multiple risk factors for CAM were identified including diabetes mellitus, inappropriate corticosteroid use, COVID-19-related hypoxia, and lung damage. Rhino-orbito-cerebral mucormycosis (ROCM) accounted for almost 90% of CAM in India while 64% of global cases were ROCM. Less than 10% of CAM from India were pulmonary while the rest of the world reported 21% of pulmonary CAM. CAM is diagnosed by confirmed SARS-CoV2 infection along with clinical, radiological, histopathological, and/or microbiological evidence of mucormycosis. In patients with risks of CAM and associated symptoms, CT or MRI are recommended. If ROCM is suspected, endoscopy and biopsy are recommended. If pulmonary CAM is suspected, tissue biopsies, nasal samples, or bronchoalveolar lavage is recommended with histopathological exams. Early diagnosis, surgical, and pharmaceutical interventions are key to treat mucormycosis. Upon diagnosis, antifungal therapy with liposomal amphotericin B (IV) is considered first-line of therapy. Alternatively, posaconazole (PO/IV) or isavuconazole (PO/IV) can be used. Conclusion Treating CAM requires a multidisciplinary approach for early diagnosis and prompt initiation of interventions to maximize patient’s chance of survival.
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- 2022
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5. Triple Collocation of Ground-, Satellite- and Land Surface Model-Based Surface Soil Moisture Products in Oklahoma—Part I: Individual Product Assessment
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Zhen Hong, Hernan A. Moreno, Zhi Li, Shuo Li, John S. Greene, Yang Hong, and Laura V. Alvarez
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soil moisture ,triple collocation ,SMAP ,Mesonet ,NLDAS ,intercomparison ,Science - Abstract
Improvements in soil moisture observations and modeling play a vital role in drought, water resources, flooding, and landslide management and forecasting. However, the lack of multisensor products that integrate different spatial scales (i.e., from 1 m2 to 102 km2) is a pressing need in the management and forecasting chain. Up to date, surface soil moisture estimates could be obtained through three primary approaches: (1) in situ measurements and their interpolations, (2) remote sensing observations, and (3) land surface model (LSM) outputs. Each source of soil moisture has its own spatiotemporal resolution, strengths, and weaknesses. Therefore, their correct interpretation and application require an in-depth understanding of their accuracy and appropriateness. In this study, we explore the utility of the triple collocation (TC) method for an independent assessment of three soil moisture products to characterize their uncertainty structures and make recommendations toward a potential product merge. The state of Oklahoma is an ideal domain to test the hypotheses of this work because of the presence of marked west-to-east gradients in climate, vegetation, and soils. The three target soil moisture products include (1) the remotely sensed microwave soil moisture active passive (SMAP) L3_SM_P_E (9 km, daily), (2) the physically based LSM estimates from NLDAS_NOAH0125_H (1/8°, hourly; Noah), and (3) the Oklahoma Mesonet ground sensor network (point, 30 min). The product assessment was conducted from April 2015 to July 2019. The results indicate that, in general, Mesonet and Noah are the most reliable products, although their performance varies geographically and by land cover type, reflecting the main spatiotemporal characteristics and scope of each product. Specifically, Mesonet provides the best estimates of volumetric soil moisture with a mean Pearson correlation coefficient of 0.805, followed by Noah with 0.747. However, Noah represents the true soil moisture variation better than the interpolated Mesonet product on the mesoscale, with an averaged RMSE of 0.026 m3⁄m3. Over different land cover types, Mesonet had the best performance in shrub/scrub, herbaceous, hay/pasture, and cultivated crops with an average correlation coefficient of 0.79, while Noah achieved the best performance in evergreen, mixed, and deciduous forests, with an average correlation coefficient of 0.74. The period-integrated TC intercomparison results over nine climate divisions indicated that Noah outperformed in the central, northeast, and east-central regions. TC provides not only a new perspective for comparatively assessing multisource soil moisture products but also a basis for objective data merging to capitalize on the strengths of multisensor, multiplatform soil moisture products.
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- 2022
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6. COVID-19 in Immunocompromised Cancer Patients: A Case Series and Review of the Literature
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Raj H. Patel MBA, Rachana Vanaparthy MBBS, and John N. Greene MD, FACP
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
The global pandemic of the novel coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has presented newfound challenges to the oncology community regarding management of disease progression in immunocompromised and cancer patients. Further, the large influx of COVID-19 patients has overwhelmed healthcare facilities, limited access to intensive care unit beds and ventilators, and canceled elective surgeries causing disruptions to the cancer care continuum and re-organization of oncological care. While it is known that the potential threat of infection is greatest in elderly patients (>60 years of age) and patients with underlying comorbidities, there is still insufficient data to determine the risk of COVID-19 in cancer patients. Given the immunosuppressive status in cancer patients arising from chemotherapy and other comorbidities, management of COVID-19 in this patient population carries a unique set of challenges. We report three cases of COVID-19 in immunocompromised cancer patients and discuss the challenges in preventing, diagnosing, and treating this vulnerable group.
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- 2021
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7. Preventing the Spread: A Comprehensive Cancer Center’s Journey to Prevent the Spread of Coronavirus Disease (Covid-19) During the 2020 Pandemic
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Stephanie Carraway MPH, CIC, CER, Stacy Martin RN, BSN, CIC, FAPIC, and John N. Greene MD
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background: On March 11, 2020, the World Health Organization (WHO) declared Coronavirus Disease (COVID-19) a pandemic. Hospitals around the world began to implement infection prevention and control (IPC) measures to stop further spread and prevent infections within their facilities. Healthcare organizations were challenged to develop response plans, procure personal protective equipment (PPE) that was in limited supply while continuing to provide quality, safe care. Methods: As a comprehensive cancer center with immunocompromised patients, our efforts began immediately. Preventative measures were established and, as of September 2020, over 14,000 patients have been tested within the facility. From March 2020 through September 2020, only one case of hospital acquired (HA) COVID-19 was identified among our patients. Two cases of suspected community acquired (SCA) cases were also identified. Following the Centers for Disease Control (CDC) guidance, IPC measures were implemented within the facility as information science about the virus developed. This article addresses the IPC measures taken, such as enhancing isolation precautions, implementing screening protocols, disinfecting and reusing N95 respirators, by the center throughout the pandemic as well as the challenges that arouse with a new and emerging infectious disease. Conclusions: The infection control measures implemented at our comprehensive cancer center during the COVID-19 pandemic allowed our center to continue to provide world class cancer care with minimal COVID-19 infection transmission among patients and team members.
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- 2021
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8. The Presentation, Pace, and Profile of Infection and Sepsis Patients Hospitalized Through the Emergency Department: An Exploratory Analysis
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Vincent X. Liu, MD, MS, Meghana Bhimarao, MS, John D. Greene, MA, Raj N. Manickam, MS, Adriana Martinez, Alejandro Schuler, PhD, MS, Fernando Barreda, MHA, and Gabriel J. Escobar, MD
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Medical emergencies. Critical care. Intensive care. First aid ,RC86-88.9 - Abstract
Objectives:. To characterize the signs and symptoms of sepsis, compare them with those from simple infection and other emergent conditions and evaluate their association with hospital outcomes. Design, Setting, Participants, and INTERVENTION:. A multicenter, retrospective cohort study of 408,377 patients hospitalized through the emergency department from 2012 to 2017 with sepsis, suspected infection, heart failure, or stroke. Infected patients were identified based on Sepsis-3 criteria, whereas noninfected patients were identified through diagnosis codes. MEASUREMENTS AND MAIN RESULTS:. Signs and symptoms were identified within physician clinical documentation in the first 24 hours of hospitalization using natural language processing. The time of sign and symptom onset prior to presentation was quantified, and sign and symptom prevalence was assessed. Using multivariable logistic regression, the association of each sign and symptom with four outcomes was evaluated: sepsis versus suspected infection diagnosis, hospital mortality, ICU admission, and time of first antibiotics (> 3 vs ≤ 3 hr from presentation). A total of 10,825 signs and symptoms were identified in 6,148,348 clinical documentation fragments. The most common symptoms overall were as follows: dyspnea (35.2%), weakness (27.2%), altered mental status (24.3%), pain (23.9%), cough (19.7%), edema (17.8%), nausea (16.9%), hypertension (15.6%), fever (13.9%), and chest pain (12.1%). Compared with predominant signs and symptoms in heart failure and stroke, those present in infection were heterogeneous. Signs and symptoms indicative of neurologic dysfunction, significant respiratory conditions, and hypotension were strongly associated with sepsis diagnosis, hospital mortality, and intensive care. Fever, present in only a minority of patients, was associated with improved mortality (odds ratio, 0.67, 95% CI, 0.64–0.70; p < 0.001). For common symptoms, the peak time of symptom onset before sepsis was 2 days, except for altered mental status, which peaked at 1 day prior to presentation. Conclusions:. The clinical presentation of sepsis was heterogeneous and occurred with rapid onset prior to hospital presentation. These findings have important implications for improving public education, clinical treatment, and quality measures of sepsis care.
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- 2021
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9. Mucositis and oral infections secondary to gram negative rods in patients with prolonged neutropenia
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Mindy M. Sampson, Sowmya Nanjappa, and John N. Greene
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Neutropenia ,Mucositis ,Resistant Pseudomonas aeruginosa ,Infectious and parasitic diseases ,RC109-216 - Abstract
Patients with prolonged neutropenia are at risk for a variety of complications and infections including the development of mucositis and oral ulcers. The changes in oral flora during chemotherapy and its effects on the development of infections of the oral cavity have been studied with inconsistent results. However, there is evidence that supports the colonization of gram negative rods in patients undergoing chemotherapy. In this report, we present two leukemic patients who developed oral ulcers secondary to multi-drug resistant Pseudomonas aeruginosa. It is important to suspect multi-drug resistant gram negative rods in patients with prolonged neutropenia who develop gum infections despite appropriate antibiotic coverage.
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- 2017
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10. Bacillus cereus Typhlitis in a Patient with Acute Myelogenous Leukemia: A Case Report and Review of the Literature
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James D. Denham, Sowmya Nanjappa, and John N. Greene
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Infectious and parasitic diseases ,RC109-216 - Abstract
Bacillus cereus is a Gram-positive rod that is now recognized as a rare cause of frank disease in the neutropenic hematologic malignancy patient. Because this pathogen is rarely isolated in clinical specimens, no large studies exist to guide the management of these acutely ill patients. Individual case reports and case series exist in the literature describing various clinical manifestations of B. cereus in the neutropenic patient including bacteremia/septicemia, pneumonia, meningitis/encephalitis, hepatic abscesses, and gastritis. In this report, we describe a case of typhlitis caused by B. cereus in a 74-year-old female with recently diagnosed acute myelogenous leukemia (AML), and we summarize the available English language literature to draw tentative conclusions regarding the clinical manifestations of this organism.
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- 2018
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11. Treatment of Enteropathogenic Escherichia coli Diarrhea in Cancer Patients: A Series of Three Cases
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James D. Denham, Sowmya Nanjappa, and John N. Greene
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Infectious and parasitic diseases ,RC109-216 - Abstract
Enteropathogenic Escherichia coli (EPEC) is a common cause of watery diarrhea in children in the developing world and an infrequent cause of significant diarrhea in adult patients. EPEC diarrhea, while not commonly seen in cancer patients, can cause significant distress to patients, and antimicrobial choice for this condition in this patient population is not clearly delineated in the literature. We report 3 cases of EPEC diarrhea in cancer patients and discuss the use of azithromycin for successful treatment of these patients. Positive outcomes were seen while using azithromycin in our first two patients and ciprofloxacin in our third patient.
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- 2018
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12. Necrotizing Fasciitis Secondary to Aeromonas Infection Presenting with Septic Shock
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Nikhil Bhatia, Manuel Castro-Borobio, John N. Greene, and Sowmya Nanjappa
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Medicine - Abstract
This report describes a case of necrotizing fasciitis presenting with septic shock due to an Aeromonas infection. The patient cut his foot while mowing the lawn and then spent time in a pool with black mold. He began feeling ill and developed swelling and a quarter-sized black area on his right lower extremity. Despite being hemodynamically unstable with systolic blood pressure in the low 70s, the patient was transferred to our facility from outside hospital 100 miles away. Upon arriving to facility, the patient appeared to be septic and the infected area of skin had grown. Irrigation and debridement were performed and appropriate antibiotic therapy was given; however, the patient subsequently died on hospital day 8. On review of the literature, cases of necrotizing fasciitis due to Aeromonas infection have been treated successfully with the aforementioned therapy; however, there is high mortality associated with these infections, many times related to a delayed diagnosis. Our patient also had multiple poor prognostic factors including hepatic dysfunction and immunosuppression.
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- 2017
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13. Two cases of disseminated infection following live organism anti-cancer vaccine administration in cancer patients
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James D. Denham, Dae Hyun Lee, Manuel Castro, Shuchi Pandya, Sadaf Aslam, Sowmya Nanjappa, and John N. Greene
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Infectious and parasitic diseases ,RC109-216 - Abstract
Vaccines containing live attenuated bacterial or viral organisms are currently being investigated as potential therapy for locally advanced or metastatic cancers. However, the use of such live organisms in an immunocompromised population, such as patients who recently or are currently receiving chemotherapy, raises the concern that these organisms can themselves disseminate and cause frank infection. We report a hereunto unreported phenomenon of anti-cancer vaccines (containing live attenuated organisms) leading to frank, disseminated infection. We submit that occurrence of this phenomenon must be watched for by all members of the interdisciplinary cancer treatment team. Keywords: Vaccine-induced disease, Anti-cancer vaccine, Listeria monocytogenes, Adenovirus
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- 2018
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14. Production, Collection, and Purification of 47Ca for the Generation of 47Sc through Isotope Harvesting at the National Superconducting Cyclotron Laboratory
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Hannah K. Clause, John P. Greene, Matthew Gott, Gregory Severin, Jennifer A. Shusterman, Wes Walker, E. Paige Abel, Colton Kalman, and Katharina Domnanich
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Detection limit ,Materials science ,Isotope ,General Chemical Engineering ,Extraction (chemistry) ,Radiochemistry ,General Chemistry ,Ion ,Semiconductor detector ,Chemistry ,Yield (chemistry) ,Particle ,Irradiation ,QD1-999 - Abstract
An experiment was performed at the National Superconducting Cyclotron Laboratory using a 140 MeV/nucleon 48Ca beam and a flowing-water target to produce 47Ca for the first time with this production route. A production rate of 0.020 ± 0.004 47Ca nuclei per incoming beam particle was measured. An isotope harvesting system attached to the target was used to collect radioactive cationic products, including 47Ca, from the water on a cation-exchange resin. The 47Ca collected was purified using three separation methods optimized for this work: (1) DGA extraction chromatography resin with HNO3 and HCl, (2) AG MP-50 cation-exchange resin with an increasing concentration gradient of HCl, and (3) AG MP-50 cation-exchange resin with a methanolic HCl gradient. These methods resulted in ≥99 ± 2% separation yield of 47Ca with 100% radionuclidic purity within the limits of detection for HPGe measurements. Inductively coupled plasma-optical emission spectrometry (ICP-OES) was used to identify low levels of stable ions in the water of the isotope harvesting system during the irradiation and in the final purified solution of 47Ca. For the first time, this experiment demonstrated the feasibility of the production, collection, and purification of 47Ca through isotope harvesting for the generation of 47Sc for nuclear medicine applications.
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- 2020
15. Pulmonary Talcosis in an Immunocompromised Patient
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Thanh-Phuong Nguyen, Sowmya Nanjappa, Manjunath Muddaraju, and John N. Greene
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Medicine - Abstract
The first case of pulmonary talcosis or talc pneumoconiosis related to inhalation of talc during its extraction and processing in mines was described by Thorel in 1896. Pulmonary talcosis is most commonly seen secondary to occupational exposure or intravenous (IV) drug abuse and, occasionally, in excessive use of cosmetic talc. Based on literature review, there has been an increase in reported incidents of pulmonary talcosis due to various forms of exposure to the mineral. We report an 82-year-old man who is diagnosed with Philadelphia chromosome positive pre-B cell acute lymphoblastic leukemia (ALL) treated with palliative imatinib who presented with chronic hemoptysis and dyspnea shortly after his diagnosis. His symptoms were initially thought to be due to an infectious etiology due to his malignancy, immunocompromised state, and radiographic findings until high-resolution computerized tomographic (HRCT) findings showed a diffuse pulmonary fibrosis picture that prompted further questioning and a more thorough history inquiry on his exposure to causative agents of interstitial lung disease. Very often, patients do not recognize their exposure, especially in those whose exposure is unrelated to their occupation. Our case emphasizes the need for thorough and careful history taking of occupational and nonoccupational exposure to known causative agents of interstitial lung disease.
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- 2016
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16. A case of endogenous trichosporon endophthalmitis treated with micafungin and voriconazole
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Harpreet Walia, Veronica T Tucci, John N Greene, Jennifer Tordilla-Wadia, Patrick Kelty, and Sandeep Walia
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Endophthalmitis ,Micafungin ,Voriconazole ,Infectious and parasitic diseases ,RC109-216 - Abstract
Invasive fungal infections are a significant cause of morbidity and mortality. Endogenous fungal endophthalmitis is a rare intraocular infection with potential vision threatening consequences. Our review of the literature revealed only one other case of Trichosporon endophthalmitis. Ocular fungal infections are difficult to eradicate because of the limited availability of systemic and intravitreal therapeutic agents and poor tissue penetration of current antifungals. Along with systemic antifungal agents, vitrectomy and intravitreal amphotericin B have been suggested as optimal treatments for fungal endophthalmitis. Other antifungals such as flucytosine and triazoles have recently received consideration. Although the current antifungal therapy is not highly successful, there remains a significant potential for more successful treatments in the future, based on the current studies. We report a case of endogenous trichosporon endophthalmitis that was successfully treated with micafungin and voriconazole. This combination has not been previously reported as a successful therapy in literature. More targeted research is required to uncover additional efficacious therapies to combat trichosporon.
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- 2009
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17. New constraints on the Al25(p,γ) reaction and its influence on the flux of cosmic γ rays from classical nova explosions
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T. Lauritsen, Jordi José, L. Canete, D. T. Doherty, Sergio Almaraz-Calderon, Anu Kankainen, R. V. F. Janssens, G. Christian, R. Wilkinson, W. N. Catford, D. Seweryniak, Gavin Lotay, S. Hallam, H. M. Albers, S. Zhu, C. J. Chiara, E. A. Bennett, John P. Greene, M. Moukaddam, Shuya Ota, M. P. Carpenter, Calem Hoffman, Antti Saastamoinen, and A. Matta
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Physics ,Nuclear reaction ,Radiative capture ,Flux ,Resonance ,Nova (laser) ,Atomic physics ,Spectroscopy - Abstract
The astrophysical $^{25}\mathrm{Al}(p,\ensuremath{\gamma})\phantom{\rule{0.16em}{0ex}}^{26}\mathrm{Si}$ reaction represents one of the key remaining uncertainties in accurately modeling the abundance of radiogenic $^{26}\mathrm{Al}$ ejected from classical novae. Specifically, the strengths of key proton-unbound resonances in $^{26}\mathrm{Si}$, that govern the rate of the $^{25}\mathrm{Al}(p,\ensuremath{\gamma})$ reaction under explosive astrophysical conditions, remain unsettled. Here, we present a detailed spectroscopy study of the $^{26}\mathrm{Si}$ mirror nucleus $^{26}\mathrm{Mg}$. We have measured the lifetime of the ${3}^{+}$, 6.125-MeV state in $^{26}\mathrm{Mg}$ to be $19(3)\phantom{\rule{0.28em}{0ex}}\mathrm{fs}$ and provide compelling evidence for the existence of a ${1}^{\ensuremath{-}}$ state in the $T=1,\phantom{\rule{0.28em}{0ex}}A=26$ system, indicating a previously unaccounted for $\ensuremath{\ell}=1$ resonance in the $^{25}\mathrm{Al}(p,\ensuremath{\gamma})$ reaction. Using the presently measured lifetime, together with the assumption that the likely ${1}^{\ensuremath{-}}$ state corresponds to a resonance in the $^{25}\mathrm{Al}+p$ system at 435.7(53) keV, we find considerable differences in the $^{25}\mathrm{Al}(p,\ensuremath{\gamma})$ reaction rate compared to previous works. Based on current nova models, we estimate that classical novae may be responsible for up to $\ensuremath{\approx}15%$ of the observed galactic abundance of $^{26}\mathrm{Al}$.
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- 2021
18. NUTRITIONALLY VARIANT STREPTOCOCCI BACTEREMIA IN CANCER PATIENTS: A RETROSPECTIVE STUDY, 1999-2014
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Abraham Tareq Yacoub, Jayasree Krishnan, Ileana M. Acevedo, Joseph Halliday, and John Norman Greene
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Nutritionally variant streptococci ,Bacteremia ,Neutropenia ,Immunocompromised ,Endocarditis ,Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
Backgound Nutritionally variant Streptococci (NVS), Abiotrophia and Granulicatella are implicated in causing endocarditis and blood stream infections more frequently than other sites of infection. Neutropenia and mucositis are the most common predisposing factors for infection with other pathogens in cancer patients. In this study we investigated the clinical characteristics of NVS bacteremia in cancer patients and identified risk factors and outcomes associated with these infections. Materials and Methods We retrospectively reviewed all cases of NVS bacteremia occurring from June 1999 to April 2014 at H. Lee Moffitt Cancer Center and Research Institute. The computerized epidemiology report provided by the microbiology laboratory identified thirteen cancer patients with NVS bacteremia. We collected data regarding baseline demographics and clinical characteristics such as age, sex, underlying malignancy, neutropenic status, duration of neutropenia, treatment, and outcome. Results Thirteen patients were identified with positive NVS blood stream infection. Ten patients (77%) had hematologic malignancies, including chronic lymphocytic leukemia (CLL) (1), multiple myeloma (MM) (1), acute myelogenous leukemia (AML) (4), and non Hodgkin’s lymphoma (NHL) (4). The non-hematologic malignancies included esophageal cancer (2) and bladder cancer (1). Conclusion NVS should be considered as a possible agent of bacteremia in cancer patients with neutropenia and a breach in oral, gastrointestinal and genitourinary mucosa (gingivitis/mucositis).
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- 2015
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19. A Case of Rupioid Syphilis Masquerading as Aggressive Cutaneous Lymphoma
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Jonathan Braue, Thomas Hagele, Abraham Tareq Yacoub, Suganya Mannivanan, Frank Glass, Lubomir Sokol, and John Norman Greene
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Syphilis ,Immunocompromised ,Cutaneous lymphoma ,Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
Secondary syphilis has been known since the late 19th century as the great imitator; however, some experts now regard cutaneous lymphoma as the great imitator of skin disease. Either disease, at times an equally fastidious diagnosis, has reported to even mimic each other. It is thus vital to consider these possibilities when presented with a patient demonstrating peculiar skin lesions. No other manifestation of secondary syphilis may pose such quandary as a rare case of rupioid syphilis impersonating cutaneous lymphoma. We present such a case, of a 36-year-old HIV positive male, misdiagnosed with aggressive cutaneous lymphoma, actually exhibiting rupioid syphilis thought secondary to immune reconstitution inflammatory syndrome (IRIS).
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- 2015
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20. DIAGNOSTIC VALUE OF BRONCHOALVEOLAR LAVAGE IN LEUKEMIC AND BONE MARROW TRANSPLANT PATIENTS: THE IMPACT OF ANTIMICROBIAL THERAPY
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John Norman Greene, Abraham Tareq Yacoub, Dani Thomas, Carol Yuan, Frank Walsh, David Solomon, Skai Schwartz, and Arthur Andrews
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Hematopoietic stem cell transplantation ,Pneumonia ,Bronchoalveolar lavage ,Bronchoscopy ,Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
Background Pneumonia carries significant morbidity and mortality in leukemic and bone marrow transplant patient. The development of pulmonary infiltrates in the setting of such immunocompromise raises concern for both infectious and non-infectious etiologies, some of which are potentially treatabl. Performing bronchoscopy provides several different options for sampling the lower respiratory tract. Among these, bronchoalveolar lavage (BAL) is especially effective at collecting samples from the alveoli and has been shown to be associated with less risk than transbonchial biops. We sought to examine the effect of antimicrobial treatment on BAL results in a large study population of leukemic and bone marrow transplant patients. Subjects and Methods This retrospective chart review was performed at a single academic cancer center. A power analysis was performed to determine the appropriate sample size. The patients were selected from those who had undergone an inpatient bronchoscopy in reverse chronological order until 300 patients with either a hematopoietic stem cell transplant or hematologic malignancy were identified. The exclusion criteria were age
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- 2014
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21. NF- κB Essential Modulator Deficiency Leading to Disseminated Cutaneous Atypical Mycobacteria
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Jonathan Braue, Vagishwari Murugesan, Steven Holland, Nishit Patel, Eknath Naik, Jennifer Leiding, Abraham Tareq Yacoub, Carlos N Prieto-Granada, and John Norman Greene
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Immunodeficiency, NEMO, rare diseases, mycobacterial Infections ,Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
NF- κB essential modulator (NEMO) is a kinase integral to the macrophage TNF-α pathway, which leads to the intracellular destruction of Mycobacteria species. Defects in the NEMO pathway lead to a spectrum of diseases, including but not limited to ectodermal dysplasia, Mendelian susceptibility to mycobacterial diseases, and incontinentia pigmenti. In addition, paucity of NEMO can lead to the inability to mount a proper immune response against opportunistic pyogenic and mycobacterial infections, leading to dissemination to various organ systems. This manuscript will discuss the numerous clinical manifestations of NEMO deficiency, the differential diagnosis for atypical mycobacterial infections in immunocompetent adults, and feature a case report of rare isolated susceptibility to disseminated atypical mycobacteria due to a mutation in the first exon of the NEMO gene.
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- 2014
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22. Cryptococcus gattii, Florida, USA, 2011
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Rajesh Kunadharaju, Ulyee Choe, Julie R. Harris, Shawn R. Lockhart, and John N. Greene
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Fungi ,Florida ,Cryptococcus gattii ,pneumonia ,meningitis ,septic arthritis ,Medicine ,Infectious and parasitic diseases ,RC109-216 - Published
- 2013
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23. 240Pu target preparation on thin backing foils for GRETINA experiments using ATLAS
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Shaofei Zhu, Matthew Gott, and John P. Greene
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Materials science ,Spin states ,Physics::Instrumentation and Detectors ,Phonon ,Health, Toxicology and Mutagenesis ,Condensation ,Public Health, Environmental and Occupational Health ,Oxide ,chemistry.chemical_element ,Coulomb excitation ,Pollution ,Molecular physics ,Analytical Chemistry ,Plutonium ,Physics::Fluid Dynamics ,chemistry.chemical_compound ,Nuclear Energy and Engineering ,chemistry ,Plating ,Physics::Accelerator Physics ,Radiology, Nuclear Medicine and imaging ,Dissolution ,Spectroscopy - Abstract
Recent measurements of the octupole strength to the highest spin states in 240Pu were performed using sub-barrier Coulomb excitation in order to unambiguously and convincingly demonstrate the existence of the rotational-aligned phonon condensation in this nucleus. The 240Pu targets were prepared at the Center for Accelerator Target Science by molecular plating onto thin backing foils of C and Al. The required plutonium oxide dissolution, molecular plating methodology, plating results, and in-beam target performance will be discussed.
- Published
- 2019
24. THE ROLE OF CORTICOSTEROIDS IN ADULT RESPIRATORY DISTRESS SYNDROME CAUSED BY VIRIDANS GROUP STREPTOCOCCI BACTEREMIA IN NEUTROPENIC PATIENTS
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Abraham Tareq Yacoub, Lysenia Mojica, Lily Jones, Andrea Knab, Sally Alrabaa, and John Norman Greene
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Bacteremia ,Streptococcus mitis ,Neutropenia ,Adult respiratory distress syndrome ,Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
Introduction During the last decades, gram-positive bacteremia has increased dramatically. Gram-positive cocci are the most frequent cause of nosocomial bloodstream infections. Among Gram-positive cocci, Viridans streptococci are a common cause of bacteremia in cancer patients with neutropenia, causing serious complications such as pneumonia, septic shock, and ARDS [1-6]. We present a series of cases of VGS bacteremia complicated with ARDS; early initiation of corticosteroids resulted in complete recovery. Materials and Methods A retrospective chart review of patients with hematologic malignancy diagnosed with VGS bacteremia admitted to the Moffitt Cancer Center in Tampa, Florida between 1/1/2001 and 4/1/2012 was completed. Data was collected about respiratory symptoms, diagnosis of adult respiratory syndrome, results of blood cultures, medications received and outcome. Results In this study, 70 cases of VGS bacteremia in neutropenic patients were reviewed. The most common adverse event of VGS bacteremia in this group of patients is the development of serious pulmonary complications such as ARDS. In our study, 7 patients developed ARDS. The most common identifies streptococcal species was Streptococcus mitis, isolated in 4 of 7 patients. All 7 patients received corticosteroids early with the onset of respiratory failure. The most commonly prescribed regimen was methylprednisolone 60 mg intravenously every 12 hour for an average of 3 days. All patients received comparable supportive care, appropriate antibiotics, ventilation and hemodynamic support. All patients (100 %) recovered from respiratory failure after receiving corticosteroids. There were no significant adverse events attributable to steroids use. Conclusion Streptococcus mitis is the species most frequently isolated from the patients who have developed ARDS from Streptococcus viridans bacteremia. Our data suggest that the early administration of corticosteroids to neutropenic patients who develop early signs of respiratory failure with VGS bacteremia can prevent the progression of ARDS and improve mortality. Moderate doses of steroids with short duration of administration were not associated with significant adverse events in our case series. While the use of corticosteroids in this setting has been described in the literature since the early 1990s, there remains a scarcity of data and our study help shed some light on this area. Moreover there is little recognition among clinicians of the association between ARDS and VGS bacteremia (particularly mitis species in neutropenic cancer patients) and thus this treatment modality is used late in the course of illness which may reduce benefit. Further studies are warranted to validate these findings and to further examine the utility of preemptive use of corticosteroids in cancer patients who develop VGS bacteremia, in regards to ARDS incidence reduction.
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- 2014
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25. ESCHERICHIA COLI: AN IMPORTANT PATHOGEN IN PATIENTS WITH HEMATOLOGIC MALIGNANCIES
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Daniel Olson, Abraham Tareq Yacoub, Gelenis Domingo, and John Norman Greene
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Escherichia Coli ,Neutropenia ,Bone Marrow Transplant ,Hematological Malignancy ,Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
Abstract Background Escherichia coli (E. coli) is a pathogen of great concern in immunosuppressed patients. While antimicrobial prophylactic therapy has become the standard, the emergence of resistant pathogens has some questioning its use. This study describes our experience with E.coli as a pathogen in neutropenic patients with a hematologic malignancy, and addresses future directions of treatment for this patient population. Methods A retrospective chart review of 245 E.coli bacteremia patients at Moffitt Cancer Center from 05/18/02 – 05/15/12 was conducted. Patients were identified via microbiology laboratory computerized records. Results The included patients experienced clinically significant E.coli bacteremia resulting in a median hospital stay of 14.7 days. Several patients developed severe sepsis requiring the use of pressor and ventilator therapy. Conclusions E.coli is a major pathogen in these patient populations resulting in extended hospital stays and specialized treatment to overcome their E.coli bacteremia. The data supports the use of fluoroquinolone prophylactic therapy, however, earlier detection and treatment of neutropenic infection is needed.
- Published
- 2014
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26. Treatment of Infections following Hematopoietic Stem Cell Transplantation.
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John Norman Greene, Abraham Tareq Yacoub, Sai Sreenija Dukkipati, and Ana Paula Velez
- Subjects
Hematopoietic stem cell transplant ,Viral infections ,Fungal infections ,Bacterial infections ,Toxoplasmosis. ,Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
The use of hematopoietic cell transplant (HCT) for the treatment of hematological malignancies has continued to grow over the last 10 years. . The development of new treatment strategies has minimized the severity and duration of immune suppression following transplantation. This article will review the management and challenges of the most common encountered infections after HCT.
- Published
- 2014
27. Bordetella Bronchiseptica in the Immunosuppressed Population – A Case Series and Review.
- Author
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Abraham Tareq Yacoub, Mitsuya Katayama, JoAnn Tran, Ronit Zadikany, Manasa Kandula, and John Norman Greene
- Subjects
Bordetella Bronchiseptica, Immunocompromised, Antibiotics ,Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
Organisms that are not known to cause serious infection in the immunocompetent population can in fact cause devastating illness in immunosupressed neutropenic populations especially those who are undergoing hematopoietic stem cell transplantation (HSCT), and solid organ transplantation or a history of malignancy. One organism of interest isolated from immunosupressed patients at our institution was Bordetella bronchiseptica. B. bronchiseptica is a Gram-negative, rod shaped bacterium, primary respiratory tract organism known to cause respiratory tract disease in the animal population which include dogs, cats, and rabbits. This organism rarely causes serious infection in the immunocompetent population. However; in immunosupressed patients, it can cause serious pulmonary disease. We present three cases of B. bronchiseptica isolated from patients with a history of malignancy a serious pulmonary infection.
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- 2014
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28. Tacrolimus Associated Posterior Reversible Encephalopathy Syndrome – A Case Series and Review
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Susmitha Apuri, Kristin Carlin, Edward Bass, Phuong Thuy Nguyen, and John Norman Greene
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PRES ,Tacrolimus ,Acute myeloid leukemia ,Bone marrow transplant ,Graft versus host disease ,Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
Tacrolimus is an immunosuppressive drug mainly used to lower the risk of transplant rejection in individuals who are post solid organ or hematopoietic transplantation. It is a macrolide which reduces peptidyl-propyl isomerase activity and inhibits calcineurin, thus inhibiting T-lymphocyte signal transduction and interleukin-2 (IL-2) transcription. It has been associated with Posterior Reversible Encephalopathy Syndrome (PRES), a disease of sudden onset that can present as a host of different symptoms, depending on the affected area of the brain. While infectious causes of encephalopathy must always be entertained, the differential diagnosis should also include PRES in the appropriate context. We report three cases of PRES in patients with acute myeloid leukemia (AML) placed on tacrolimus after receiving a bone marrow transplant (BMT). The focus of this review is to enhance clinical recognition of PRES as it is related to an adverse effect of Tacrolimus in the setting of hematopoietic transplantation.
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- 2014
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29. Possible quenching of static neutron pairing near the N=98 deformed shell gap: Rotational structures in Gd160,161
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Sanna Stolze, T. Lauritsen, John P. Greene, A. J. Boston, J. Li, G. L. Wilson, S. Zhu, J. Heery, Jayne Simpson, C. R. Hoffman, P. Jackson, F. G. Kondev, K. Villafana, Guy Savard, E. S. Paul, M. P. Carpenter, D. Little, S. Frauendorf, M. A. Riley, Kalle Auranen, Jin Wu, D. J. Hartley, R. V. F. Janssens, Jill S. Baron, Jason A. Clark, D. Seweryniak, and A. D. Ayangeakaa
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Quenching ,Physics ,Pairing ,Shell (structure) ,Neutron ,Molecular physics - Published
- 2021
30. First observation of excited states in the Ce96154 nucleus: Rigid rotation at Z=58
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G. S. Simpson, John P. Greene, A. G. Smith, W. Urban, and T. Rząca-Urban
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Physics ,Proton ,010308 nuclear & particles physics ,Fission ,Nuclear Theory ,Rotation ,01 natural sciences ,medicine.anatomical_structure ,Excited state ,Neutron number ,0103 physical sciences ,medicine ,Neutron ,Atomic physics ,Nuclear Experiment ,010306 general physics ,Nucleus ,Spontaneous fission - Abstract
A new analysis of the data from measurements of $\ensuremath{\gamma}$ radiation following spontaneous fission of $^{248}\mathrm{Cm}$ and $^{252}\mathrm{Cf}$, performed using the Eurogam2 and Gammashpere arrays, respectively, has revealed, for the first time, excited states in the neutron-rich nucleus $^{154}\mathrm{Ce}_{96}$. Using these fission data we have also improved uncertainties on $\ensuremath{\gamma}$-ray energies in the ground-state bands of several neutron-rich nuclei of the $\mathrm{A}\ensuremath{\approx}150$ mass region. The improved data provided precise systematics of the ${\mathrm{E}}_{\mathrm{exc}}({4}^{+})/{\mathrm{E}}_{\mathrm{exc}}({2}^{+})$ ratio in the region, which indicate that, in the Ce isotopic chain, the rigid-rotation limit is reached at the neutron number $N=96$, two neutrons ``later'' than in the chain of Nd isotopes. The new results suggest the involvement of the proton $9/{2}^{+}[404]$ extruder orbital in generating nuclear deformation in the $\mathrm{A}\ensuremath{\approx}150$ region, in addition to and analogous to the known role played by the neutron $11/{2}^{\ensuremath{-}}[505]$ extruder in this region. The catalytic-type action of both extruders is discussed.
- Published
- 2020
31. Human geranylgeranyl diphosphate synthase: isolation of the cDNA, chromosomal mapping and tissue expression
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Johan Ericsson, John M. Greene, Kenneth C. Carter, Brenda K. Shell, D. Roxanne Duan, Charles Florence, and Peter A. Edwards
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prenyltransferase ,Biochemistry ,QD415-436 - Abstract
We report the nucleotide sequence of human geranylgeranyl diphosphate (GGPP) synthase cDNA isolated from a fetal heart library. The 2.5 kb cDNA encodes a protein of 34 kDa. The protein contains six domains that have been identified previously in many other prenyltransferases. Recombinant, purified histidine-tagged protein exhibited the enzymatic properties associated with GGPP synthase, namely the synthesis of GGPP from farnesyl diphosphate and isopentenyl diphosphate. Transient transfection of mammalian cells with a plasmid encoding the putative GGPP synthase resulted in a 55-fold increase in GGPP synthase activity. Taken together, these results establish that the cDNA encodes the mammalian GGPP synthase protein. The mRNA for GGPP synthase was expressed ubiquitiously. Of the 16 human tissues examined, the highest expression of the mRNA was in testis. The mRNA levels in cultured HeLa cells were unaffected by alterations in cellular sterol levels and contrasted with the significant regulation of isopentenyl diphosphate synthase mRNA under these same conditions. Fluorescent in situ hybridization was used to map the single gene encoding human GGPP synthase to chromosome 1q43.—Ericsson, J., J. M. Greene, K. C. Carter, B. K. Shell, D. R. Duan, C. Florence, and P. A. Edwards. Human geranylgeranyl diphosphate synthase: isolation of the cDNA, chromosomal mapping, and tissue expression.
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- 1998
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32. Reply to: Possible overestimation of isomer depletion due to contamination
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J. Rzadkiewicz, John P. Greene, D. Seweryniak, Marek Polasik, M. P. Carpenter, A. B. Hayes, D. J. Hartley, S. Zhu, D. A. Matters, C. J. Chiara, J. J. Carroll, G. J. Lane, J. C. Marsh, R. V. F. Janssens, and S. Bottoni
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Multidisciplinary ,Chemistry ,Environmental chemistry ,Contamination - Published
- 2021
33. Socioeconomic Predictors of Family Forest Owner Awareness and Use of U.S. Federal Income Tax Provisions
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John E. Hatcher, Thomas J. Straka, Tamara L. Cushing, John L. Greene, and William C. Bridges
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federal income tax ,family forest ,capital gains tax ,seven-year amortization ,Plant ecology ,QK900-989 - Abstract
Family forest owners (FFOs) control a majority of private forestland in the United States and have widely diverse ownership and management objectives. Many FFOs manage their holdings for timber production and, thus, are concerned with issues such as reforestation incentives and tax treatment of timber revenues. Their actual knowledge of the tax aspects of timber management varies, with some owners even unaware of the federal income tax provisions that apply to timber. This research used econometric techniques to establish socioeconomic predictors of FFO awareness and use of federal income tax provisions. Socioeconomic factors (such as size of forest holding, ownership objective, education, age, and income) were evaluated in terms of association with awareness and use of income tax provisions. Data were obtained from a survey of 1350 South Carolina FFOs (472 useable responses). A two-step sample selection methodology revealed that membership in a landowner organization and size of forest holding positively influence landowner awareness of the seven tax provisions, while ownership objective and level of education exhibited varying degrees of influence. Overall, the findings suggest that size of forest holding is the key determinant that influences landowner use of the provisions. These tax incentives are one of the foundations of federal policies encouraging active forest management by FFOs and the effectiveness of the various incentives has crucial implications for forest policy analysis.
- Published
- 2016
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34. State-of-the-art γ -ray assay of Y86 for medical imaging
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C. J. Lister, E. A. McCutchan, John P. Greene, S. Zhu, Robert J. Nickles, Suzanne V. Smith, Paul A. Ellison, A. C. Gula, Alejandro Sonzogni, and M. P. Carpenter
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Physics ,Isotope ,Image (category theory) ,Medical imaging ,Gammasphere ,Positron emission ,State (functional analysis) ,Atomic physics ,National laboratory ,Coupling (probability) - Abstract
An emerging direction in nuclear medicine is the coupling of a therapeutic isotope with an imaging isotope to form a so-called theranostic pair, which allows one to quantitatively track and image the delivery of the therapeutic isotope. $^{90}\mathrm{Y}$ is used in several therapy applications and a convenient candidate imaging partner is the positron emitter $^{86}\mathrm{Y}$. A 27.6 MBq source of $^{86}\mathrm{Y}$ was produced at the University of Wisconsin and assayed with the Gammasphere array at Argonne National Laboratory. Over 200 $\ensuremath{\gamma}$-ray transitions were identified, more than double that which was previously known. The positron emission probability inferred from the present level scheme leads to 27.9(12)%, an important $(\ensuremath{\approx}14%)$ reduction with respect to the previously recommended value.
- Published
- 2020
35. New, low-energy excitations in Mo107 and Mo109
- Author
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John P. Greene, J. Wiśniewski, T. Rząca-Urban, A. Płochocki, G. S. Simpson, J. Kurpeta, W. Urban, and A. G. Smith
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Physics ,010308 nuclear & particles physics ,Prolate spheroid ,01 natural sciences ,Low energy ,Excited state ,0103 physical sciences ,Gammasphere ,Atomic physics ,Nuclear Experiment ,010306 general physics ,Spectroscopy ,Ground state ,Energy (signal processing) ,Spontaneous fission - Abstract
New ground-state level with spin-parity $1/{2}^{+}$ is established in $^{109}\mathrm{Mo}$, 69.8 keV below the previously reported $5/{2}^{+}$ ground state in this nucleus, based on precise spectroscopy measurements of $\ensuremath{\gamma}$ radiation following spontaneous fission of $^{248}\mathrm{Cm}$ performed using the Eurogam2 array of anti-Compton spectrometers. Analogous measurement of $\ensuremath{\gamma}$ radiation following spontaneous fission of $^{252}\mathrm{Cf}$, performed using the Gammasphere array, confirms the new $1/{2}^{+}$ ground state of $^{107}\mathrm{Mo}$, proposed recently and establishes the isomeric character of the $5/{2}^{+}$ first excited state in $^{107}\mathrm{Mo}$. Two $\ensuremath{\beta}$-decaying isomers are suggested in $^{111}\mathrm{Mo}$ nucleus based on regular energy systematics, supporting previous predictions. Low-energy excitations in Mo isotopes are interpreted and compared to calculations reported in the literature. The results suggest shape transition from prolate to oblate deformation at $N\ensuremath{\ge}67$.
- Published
- 2020
36. The $$^{136}\hbox {Xe} + ^{198}\hbox {Pt}$$ reaction: a detailed re-examination
- Author
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John P. Greene, S. Zhu, W. Loveland, G. J. Lane, P. Copp, R. V. F. Janssens, R. Yanez, V. V. Desai, F. G. Kondev, and A. D. Ayangekaa
- Subjects
Physics ,Nuclear and High Energy Physics ,010308 nuclear & particles physics ,Product (mathematics) ,0103 physical sciences ,Hadron ,Nuclear fusion ,Gammasphere ,Nuclide ,Atomic physics ,010306 general physics ,01 natural sciences ,Beam (structure) - Abstract
We extend previous measurements of the transfer product yields in the reaction of $$\hbox {E}_{c.m.} = 450\hbox { MeV} ^{~136}\hbox {Xe}$$ with $$^{198}\hbox {Pt}$$ by measurements of the product yields using Gammasphere. By recording events occurring in beam bursts and in between beam bursts, we are able to extend the number of measured product yields from 78 to 171 nuclides. Our new data span a much wider range of Z and A than observed in previous work and when compared to theoretical predictions, these new measurements provide a more stringent and thorough test of models of multi-nucleon transfer (MNT) reactions.
- Published
- 2020
37. Multinucleon transfer in the interaction of 977 MeV and 1143 MeV Hg204 with Pb208
- Author
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T. Lauritsen, S. Zhu, R. V. F. Janssens, J. S. Barrett, E. A. McCutchan, John P. Greene, W. Loveland, A. D. Ayangeakaa, W. B. Walters, Ashley Pica, M. P. Carpenter, V. V. Desai, and B. M. S. Amro
- Subjects
Physics ,Isotope ,010308 nuclear & particles physics ,Nuclear Theory ,01 natural sciences ,Quantum molecular dynamics ,Transfer (group theory) ,Orders of magnitude (time) ,Product (mathematics) ,Yield (chemistry) ,0103 physical sciences ,Nuclide ,Atomic physics ,Nuclear Experiment ,010306 general physics - Abstract
A previous study of symmetric collisions of massive nuclei has shown that current models of multinucleon transfer (MNT) reactions do not adequately describe the transfer product yields. To gain further insight into this problem, we have measured the yields of MNT products in the interaction of 977 ($E/A=4.79$ MeV) and 1143 MeV ($E/A=5.60$ MeV) $^{204}\mathrm{Hg}$ with $^{208}\mathrm{Pb}$. We find that the yield of multinucleon transfer products are similar in these two reactions and are substantially lower than those observed in the reaction of 1257 MeV ($E/A=6.16$ MeV) $^{204}\mathrm{Hg}+^{198}\mathrm{Pt}$. We compare our measurements with the predictions of the GRAZING-F, dinuclear systems (DNS), and improved quantum molecular dynamics (ImQMD) models. For the observed isotopes of the elements Au, Hg, Tl, Pb, and Bi, the measured values of the MNT cross sections are orders of magnitude larger than the predicted values. Furthermore, the various models predict the formation of nuclides near the $N=126$ shell, which are not observed.
- Published
- 2020
38. Study of the $^{25}$Mg(d,p)$^{26}$Mg reaction to constrain the $^{25}$Al(p,$\gamma$)$^{26}$Si resonant reaction rates in nova burning conditions
- Author
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Richard Longland, John P. Greene, Caleb Marshall, Conor Hamill, F. Portillo, Philip Woods, D. Kahl, and K. Setoodehnia
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Reaction rate ,Physics ,Nuclear and High Energy Physics ,Proton ,Astrophysics - Solar and Stellar Astrophysics ,Nuclear Theory ,Resonance ,Production (computer science) ,Nova (laser) ,Atomic physics ,Nuclear Experiment ,Resonance strength - Abstract
The rate of the $^{25}$Al($p$,$\gamma$)$^{26}$Si reaction is one of the few key remaining nuclear uncertainties required for predicting the production of the cosmic $\gamma$-ray emitter $^{26}$Al in explosive burning in novae. This reaction rate is dominated by three key resonances ($J^{\pi}=0^{+}$, $1^{+}$ and $3^{+}$) in $^{26}$Si. Only the $3^{+}$ resonance strength has been directly constrained by experiment. A high resolution measurement of the $^{25}$Mg($d$,$p$) reaction was used to determine spectroscopic factors for analog states in the mirror nucleus, $^{26}$Mg. A first spectroscopic factor value is reported for the $0^{+}$ state at 6.256 MeV, and a strict upper limit is set on the value for the $1^{+}$ state at 5.691 MeV, that is incompatible with an earlier ($^{4}$He,$^{3}$He) study. These results are used to estimate proton partial widths, and resonance strengths of analog states in $^{26}$Si contributing to the $^{25}$Al($p$,$\gamma$)$^{26}$Si reaction rate in nova burning conditions., Comment: Final version accepted and published. 6 pages and 3 figures
- Published
- 2020
39. Rhenium and iridium targets prepared using a novel graphene loading technique
- Author
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Matthew Gott, Igor Pavlovsky, John P. Greene, and Richard Lee Fink
- Subjects
Fabrication ,Materials science ,010405 organic chemistry ,Graphene ,Physics ,QC1-999 ,Refractory metals ,chemistry.chemical_element ,Nanoparticle ,Nanotechnology ,Rhenium ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,law.invention ,Outgassing ,chemistry ,law ,Gammasphere ,Iridium - Abstract
For accelerator targets, graphene films are an excellent material choice due to their high thermal conductivity, high temperature tolerance, low outgassing, mechanical integrity, and ease of handling. A variety of targets have been produced using graphene material as a backing or a host matrix. One of the unique advantages of the graphene film fabrication process is the capability to embed target materials, including refractory metals, in the nanoparticle form into a host graphene matrix during target preparation. Targets of natIr and natRe have been fabricated as nanoparticle loaded graphene targets for use in nuclear physics research. We have obtained beam time to evaluate target performance as well as production yields and nuclear decay properties via the natRe(a,2n)186Ir and natIr(a,3n)194Au reactions, respectively. These rhenium and iridium targets will be irradiated using the ATLAS accelerator and gamma rays measured in-place using the high-precision gamma-ray spectroscopy capabilities of Gammasphere and further analyzed using a multi-parameter detector system. Future plans include the preparation of isotopic targets of these two elements.
- Published
- 2020
40. Recoil-ion detection efficiency for complex β decays studied using the Beta-decay Paul Trap
- Author
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B.S. Alan, S. W. Padgett, John P. Greene, A. Perez Galvan, Eric B. Norman, Shane Caldwell, C. J. Chiara, Ani Aprahamian, S. T. Marley, J.M. Munson, K. S. Sharma, S. Strauss, K. Siegl, J. L. Harker, Guy Savard, R. Orford, Jason A. Clark, N. D. Scielzo, A. Czeszumska, and G.E. Morgan
- Subjects
Physics ,Nuclear and High Energy Physics ,Physics::Instrumentation and Detectors ,010308 nuclear & particles physics ,Branching fraction ,Neutron emission ,01 natural sciences ,Beta decay ,Ion ,Recoil ,0103 physical sciences ,Microchannel plate detector ,Ion trap ,Atomic physics ,Nuclear Experiment ,010306 general physics ,Instrumentation ,Delayed neutron - Abstract
Beta-delayed neutron emission is being studied by detecting the β particles and recoiling ions emerging from the Beta-decay Paul Trap. For β decays to the ground state or γ -emitting states of the daughter nucleus, the fraction of recoiling ions which reach the ion detector in coincidence with a β particle has been determined for 134, 135Sb, 137, 138, 140I, and 144, 145Cs. This value is needed for the determination of the β -delayed neutron emission branching ratio solely from the recoil-ion time-of-flight (TOF) spectrum. The β -particle energy and recoil-ion TOF spectra were used to constrain a simple decay model, which can be used to determine the detection efficiency. The method is compared to simulations to estimate the uncertainty introduced by incomplete knowledge of the decay pattern. By fitting the simulation results to several β -ion coincidence properties measured during the experiment, the fraction of ions which reach the microchannel plate detector can be determined to within ± 4 % . This result opens the possibility of using the recoil-ion TOF spectra for high precision β -delayed neutron branching-ratio measurements.
- Published
- 2018
41. Fast-timing measurements in the ground-state band of Pd114
- Author
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T. Lauritsen, T. Kröll, L. A. Gurgi, F. G. Kondev, G. J. Lane, I. Burrows, D. M. Cullen, O. Yordanov, S. Lalkovski, Alison Bruce, John P. Greene, T. Daniel, V. F. E. Pucknell, D. Seweryniak, D. J. Hartley, Gavin Lotay, C. M. Shand, M. Smolen, T. Berry, S. Bottoni, C. R. Niţă, E. A. Stefanova, J. Sethi, E.R. Gamba, R. Ilieva, M. Carmona Gallardo, S. Zhu, J. Rohrer, J. T. Anderson, A. D. Ayangeakaa, S. Ilieva, J. Simpson, Matthew Reed, M. P. Carpenter, P. Copp, M. Rudigier, V. Vedia, I.H. Lazarus, P. H. Regan, Raymond J. Carroll, Zs. Podolyák, and G. Fernández Martínez
- Subjects
Physics ,Work (thermodynamics) ,Isotope ,Yrast ,chemistry.chemical_element ,medicine.anatomical_structure ,chemistry ,medicine ,Gammasphere ,Interacting boson model ,Atomic physics ,Ground state ,Nucleus ,Palladium - Abstract
Using a hybrid Gammasphere array coupled to 25 LaBr3(Ce) detectors, the lifetimes of the first three levels of the yrast band in ¹¹⁴Pd populated via ²⁵²Cf decay, have been measured. The measured lifetimes are τ₂+=103(10)ps, τ₄+=22(13)ps, and τ₆+≤10ps for the 2⁺₁, 4⁺₁, and 6⁺₁ levels, respectively. Palladium-114 was predicted to be the most deformed isotope of its isotopic chain, and spectroscopic studies have suggested it might also be a candidate nucleus for low-spin stable triaxiality. From the lifetimes measured in this work, reduced transition probabilities B(E2;J→J−2) are calculated and compared with interacting boson model, projected shell model, and collective model calculations from the literature. The experimental ratio RB(E₂)=B(E2;4⁺₁→2⁺₁)/B(E2;2⁺₁→0⁺₁)=0.80(42) is measured for the first time in ¹¹⁴Pd and compared with the known values RB(E₂) in the palladium isotopic chain: the systematics suggest that, for N=68, a transition from γ-unstable to a more rigid γ-deformed nuclear shape occurs.
- Published
- 2019
42. Nucleon correlations and the structure ofZn413071
- Author
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A. Wiens, John P. Greene, S. Zhu, W. B. Walters, Takaharu Otsuka, C. M. Campbell, M. Q. Buckner, A. O. Macchiavelli, D. Seweryniak, H. L. Crawford, A. Korichi, M. Cromaz, Alexandra Gade, H. M. David, C. J. Chiara, J. Sethi, R. V. F. Janssens, P. Fallon, D. Cline, Yusuke Tsunoda, Brian Bucher, A. D. Ayangeakaa, S. Bottoni, J. L. Harker, A. B. Hayes, D. Weisshaar, M. P. Carpenter, T. Lauritsen, B. P. Kay, Calem Hoffman, and Ching-Yen Wu
- Subjects
Physics ,Nuclear and High Energy Physics ,Valence (chemistry) ,010308 nuclear & particles physics ,Nuclear Theory ,01 natural sciences ,symbols.namesake ,Pairing ,0103 physical sciences ,Oblate spheroid ,symbols ,Neutron ,Gammasphere ,Atomic physics ,Nuclear Experiment ,010306 general physics ,Nucleon ,Hamiltonian (quantum mechanics) - Abstract
The structure of 71Zn was investigated by one-neutron transfer and heavy-ion induced complex (deep-inelastic) reactions using the GRETINA-CHICO2 and the Gammasphere setups, respectively. The observed inversion between the 9/2+ and 1/2− states is explained in terms of the role of neutron pairing correlations. Non-collective sequences of levels were delineated above the 9/2+ isomeric state. These are interpreted as being associated with a modest oblate deformation in the framework of Monte-Carlo shell-model calculations carried out with the A3DA-m Hamiltonian in the p f g 9 / 2 d 5 / 2 valence space. Similarities with the structure of Ni 40 28 68 were observed and the shape-coexistence mechanism in the N = 40 region of neutron-rich nuclei is discussed in terms of the so-called Type-II shell evolution, with an emphasis on proton–neutron correlations between valence nucleons, especially those involving the shape-driving g 9 / 2 neutron orbital.
- Published
- 2017
43. Modeling multi-nucleon transfer in symmetric collisions of massive nuclei
- Author
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Timothy J. Welsh, B. M. S. Amro, J. S. Barrett, Timothy Johnson, T. Lauritsen, E. A. McCutchan, M. P. Carpenter, John P. Greene, J. L. Harker, W. Loveland, S. Zhu, A. A. Sonzogni, W. B. Walters, P. Copp, R. Yanez, and A. D. Ayangeakaa
- Subjects
Physics ,Nuclear and High Energy Physics ,Particle physics ,010308 nuclear & particles physics ,Nuclear Theory ,Collision ,01 natural sciences ,lcsh:QC1-999 ,Nuclear physics ,Transfer (computing) ,0103 physical sciences ,Current (fluid) ,010306 general physics ,Nucleon ,Nuclear Experiment ,lcsh:Physics - Abstract
Symmetric collisions of massive nuclei, such as 238U + 248Cm, have been proposed as ways to make new n-rich heavy nuclei via multi-nucleon transfer (MNT) reactions. We have measured the yields of several projectile-like and target-like fragments from the reaction of 1360 MeV 204Hg + 198Pt. We find that current models for this symmetric collision (GRAZING, DNS, ImQMD) significantly underestimate the yields of these transfer products, even for small transfers. Keywords: Multi-nucleon transfer, GRAZING predictions, DNS model, Improved Quantum Molecular Dynamics model, 204Hg + 198Pt
- Published
- 2017
44. Isomer depletion as experimental evidence of nuclear excitation by electron capture
- Author
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J. Rzadkiewicz, S. Zhu, D. Seweryniak, Gregory Lane, John P. Greene, S. A. Karamian, D. A. Matters, Marek Polasik, James Carroll, M. P. Carpenter, S. Bottoni, Robert V. F. Janssens, C. J. Chiara, D. J. Hartley, J. C. Marsh, and A. B. Hayes
- Subjects
Physics ,Multidisciplinary ,Isotope ,010308 nuclear & particles physics ,Electron capture ,Binding energy ,Electron ,Kinetic energy ,01 natural sciences ,Internal conversion ,Excited state ,0103 physical sciences ,Atomic nucleus ,Atomic physics ,010306 general physics - Abstract
The atomic nucleus and its electrons are often thought of as independent systems that are held together in the atom by their mutual attraction. Their interaction, however, leads to other important effects, such as providing an additional decay mode for excited nuclear states, whereby the nucleus releases energy by ejecting an atomic electron instead of by emitting a γ-ray. This 'internal conversion' has been known for about a hundred years and can be used to study nuclei and their interaction with their electrons. In the inverse process-nuclear excitation by electron capture (NEEC)-a free electron is captured into an atomic vacancy and can excite the nucleus to a higher-energy state, provided that the kinetic energy of the free electron plus the magnitude of its binding energy once captured matches the nuclear energy difference between the two states. NEEC was predicted in 1976 and has not hitherto been observed. Here we report evidence of NEEC in molybdenum-93 and determine the probability and cross-section for the process in a beam-based experimental scenario. Our results provide a standard for the assessment of theoretical models relevant to NEEC, which predict cross-sections that span many orders of magnitude. The greatest practical effect of the NEEC process may be on the survival of nuclei in stellar environments, in which it could excite isomers (that is, long-lived nuclear states) to shorter-lived states. Such excitations may reduce the abundance of the isotope after its production. This is an example of 'isomer depletion', which has been investigated previously through other reactions, but is used here to obtain evidence for NEEC.
- Published
- 2018
45. Decay spectroscopy of two-quasiparticle K isomers in Cm246,248 via inelastic and transfer reactions
- Author
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F. G. Kondev, S. K. Tandel, D. Seweryniak, R. V. F. Janssens, C. J. Lister, D. Peterson, T. L. Khoo, P. Chowdhury, X. Wang, John P. Greene, U. Shirwadkar, S. Zhu, I. Ahmad, T. Lauritsen, and M. P. Carpenter
- Subjects
Physics ,Decay scheme ,Isotope ,010308 nuclear & particles physics ,Quantum number ,01 natural sciences ,Transfer (group theory) ,0103 physical sciences ,Physics::Atomic and Molecular Clusters ,Quasiparticle ,Atomic physics ,010306 general physics ,Spectroscopy ,Excitation - Abstract
The decay of $K$ isomers in Cm ($Z$ = 96) isotopes has been studied using inelastic and transfer reactions. The half-life of a previously identified 2-quasiparticle (qp) ${K}^{\ensuremath{\pi}}={8}^{\ensuremath{-}}$ isomer in $^{246}\mathrm{Cm}$ has been measured. A new 2-qp isomer is observed in $^{248}\mathrm{Cm}$, its half-life measured and its decay scheme established. The reduced $K$ hindrances extracted for the decay transitions from the isomers in $^{246,248}\mathrm{Cm}$ indicate $K$ to be a robust quantum number and validate axial symmetry in these nuclei. The excitation energies of the 2-qp isomers in $^{246}\mathrm{Cm}$ ($N$ = 150) and $^{248}\mathrm{Cm}$ ($N$ = 152) support the persistence of a deformed subshell gap at $N$ = 152 in the $Z\ensuremath{\approx}100$ region down to $Z$ = 96 nuclei.
- Published
- 2019
46. Entrance channel effects on the quasifission reaction channel in Cr + W systems
- Author
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Aditya Wakhle, D. C. Rafferty, David J. Morrissey, K. Stiefel, Duc Huy Luong, K. Hammerton, David Hinde, S. D. McNeil, D. Y. Jeung, Cedric Simenel, Elizabeth Williams, Mahananda Dasgupta, Z. Kohley, John P. Greene, C. S. Palshetkar, Ian Carter, and Kaitlin Cook
- Subjects
Physics ,Work (thermodynamics) ,Fusion ,Nuclear Theory ,010308 nuclear & particles physics ,FOS: Physical sciences ,Coulomb barrier ,01 natural sciences ,7. Clean energy ,Molecular physics ,Nuclear Theory (nucl-th) ,Orders of magnitude (time) ,0103 physical sciences ,Nuclear fusion ,Neutron ,Nuclear Experiment (nucl-ex) ,Nuclear Experiment ,010306 general physics ,Excitation ,Beam (structure) - Abstract
Background: Formation of a fully equilibrated compound nucleus is a critical step in the heavy-ion fusion reaction mechanism but can be hindered by orders of magnitude by quasifission, a process in which the dinuclear system breaks apart prior to full equilibration. To provide a complete description of heavy-ion fusion it is important to characterize the quasifission process. In particular, the impact of changing the neutron richness on the quasifission process is not well known. A previous study of Cr + W reactions at a constant $13%$ above the Coulomb barrier concluded that an increase in neutron richness leads to a decrease in the prominence of the quasifission reaction channel.Purpose: The dynamics of quasifission for reactions with varying neutron richness was explored at a constant excitation energy, closer to the interaction barrier than the previous work, to see if the correlation between neutron richness and quasifission is valid at lower energies.Methods: Mass distributions were measured at the Australian National University for eight different combinations of Cr + W reactions, using the kinematic coincidence method. To eliminate the effect of differing excitation energies, measurements were made at beam energies chosen to give 52 MeV of excitation energy in all the compound nuclei.Results: A curvature parameter, describing the shape of the mass distributions, was determined for the fission-like fragment mass distributions for each reaction, and compared to various reaction parameters known to influence quasifission.Conclusions: The present work demonstrates that, at energies near the interaction barrier, the beam energy with respect to the barrier is as important as neutron-richness effects in determining the quasifission characteristics in these Cr + W reactions involving statically deformed target nuclei, and both are important considerations for future heavy and superheavy element production reactions.
- Published
- 2019
47. The Xe136+Pt198 reaction: A test of models of multi-nucleon transfer reactions
- Author
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Hirozumi Watanabe, S. Zhu, P. Copp, R. V. F. Janssens, D. Seweryniak, John P. Greene, S. S. Hota, W. Loveland, Matthew Reed, Kalle Auranen, R. Yanez, F. G. Kondev, V. V. Desai, Gregory Lane, K. McCaleb, M. P. Carpenter, and A. D. Ayangeakaa
- Subjects
Physics ,Transfer (group theory) ,Fission ,Center (category theory) ,Atomic physics ,Nuclear Experiment ,Nucleon ,Spectroscopy ,Quantum molecular dynamics ,Beam energy ,Energy (signal processing) - Abstract
The yields of 42 projectile-like fragments (PLFs) and fission fragments and 36 target-like fragments (TLFs) were measured using off-line $\ensuremath{\gamma}$-ray spectroscopy in a thin target experiment involving the $^{136}\mathrm{Xe}+^{198}\mathrm{Pt}$ reaction. The center of target beam energy was 760.5 MeV $({\mathrm{E}}_{\mathrm{c}.\mathrm{m}.}=450$ MeV). The reported yields are compared with those from previous measurements for this reaction and with predictions of the GRAZING, di-nuclear systems (DNS), and improved quantum molecular dynamics (ImQMD) models. The yields of the TLFs and PLFs are, in general, substantially smaller than those previously observed at a beam energy of 1085 MeV. Neither the GRAZING nor the DNS model correctly describes the measured TLF and PLF yields in this lower- energy reaction but the ImQMD model describes these yields adequately.
- Published
- 2019
48. Spectroscopic study and lifetime measurement of the 6d7p 3F2 state of radium
- Author
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Matthew Dietrich, John P. Greene, Tenzin Rabga, Jaideep Singh, Donald Booth, Thomas P. O'Connor, Peter Mueller, Kevin Bailey, Roy Ready, and M. Bishof
- Subjects
010302 applied physics ,Physics ,Atomic beam ,Branching fraction ,010401 analytical chemistry ,chemistry.chemical_element ,Branching (polymer chemistry) ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Fluorescence spectroscopy ,0104 chemical sciences ,Analytical Chemistry ,Radium ,chemistry ,Metastability ,Laser cooling ,0103 physical sciences ,Atomic physics ,Instrumentation ,Spectroscopy - Abstract
We report a method for the precision measurement of the oscillator strengths and the branching fractions of the decay channels of the 6d7p 3F2o state in 226Ra. This method exploits a set of metastable states present in Ra, allowing a measurement of the oscillator strengths that does not require knowledge of the number of atoms in the atomic beam. We measure the oscillator strengths and the branching fractions for decays from the 6d7p 3F2o state to the 7s6d 3D1, 7s6d 3D2, and 7s6d 1D2 states and constrain the branching fraction to the 7s6d 3D3 state to be less than 0.4% (68% confidence limit). The lifetime of the 3F2o state is determined to be 15 ± 4 ns.
- Published
- 2020
49. Towards a measurement of the half-life of 60Fe for stellar and early Solar System models
- Author
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M. Paul, Rugard Dressler, W. Bauder, W. Kutschera, T. Anderson, Wenting Lu, Philippe Collon, K. Ostdiek, Matthew Bowers, Michael Skulski, Anton Wallner, Donald Robertson, Dorothea Schumann, and John P. Greene
- Subjects
Interstellar medium ,Physics ,Nuclear and High Energy Physics ,Stars ,Solar System ,Supernova ,Gamma ray ,Astrophysics ,Decay product ,Instrumentation ,Galaxy ,Accelerator mass spectrometry - Abstract
Radioisotopes, produced in stars and ejected into the Interstellar Medium, are important for constraining stellar and early Solar System (ESS) models. In particular, the half-life of the radioisotope, Fe-60, can have an impact on calculations for the timing for ESS events, the distance to nearby Supernovae, and the brightness of individual, non-steady-state Fe gamma ray sources in the Galaxy. A half-life measurement has been undertaken at the University of Notre Dame and measurements of the Fe-60/Fe-56 concentration of our samples using Accelerator Mass Spectrometry has begun. This result will be coupled with an activity measurement of the isomeric decay in Co-60, which is the decay product of Fe. Preliminary half-life estimates of (2.53 +/- 0.24) x 10(6) years seem to confirm the recent measurement by Rugel et al. (2009). (C) 2015 Elsevier B.V. All rights reserved.
- Published
- 2015
50. Method development for producing thin 14C foils
- Author
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John P. Greene, Igor Pavlovsky, Richard Lee Fink, and Matthew Gott
- Subjects
chemistry.chemical_compound ,chemistry ,Impurity ,Physics ,QC1-999 ,Metallurgy ,Oxide ,Purification methods ,Method development ,FOIL method - Abstract
Thin, isotopic 14C foils are of great interest to the nuclear physics community as neutron-rich targets. Historically, these foils have been extremely difficult to prepare and an effort is underway to make them readily available. The stock material of 14C available at Argonne contains a number of oxide impurities (SiO2, MgO, and Al2O3), which affect the composition and stability of the fabricated foil. A simple, robust method was developed (using natC as a surrogate) to purify the 14C material while minimizing loss and potential spread of the material. Thin foils were fabricated using the purified carbon, the unpurified carbon/oxide mix, and purchased high-purity carbon powder. SEM and EDS of the resulting foils was performed and the efficacy of this purification method was demonstrated.
- Published
- 2020
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