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Potter AE, Baker C, Shumack S, Sinclair R, Curran WJ, Christie D, Wong B, Foley P, O’Brien P, Spelman L. Preliminary efficacy and safety analysis: 12-month results in 83 patients using a novel approach of widefield radiation therapy for extensive skin field cancerization with or without keratinocyte cancers. J DERMATOL TREAT 2022; 33:2634-2642. [DOI: 10.1080/09546634.2022.2067814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
| | - Christopher Baker
- Department of Dermatology, St Vincent’s Hospital Melbourne, Fitzroy, Australia
- Department of Medicine, The University Melbourne, Melbourne, Australia
| | - Stephen Shumack
- Sydney Medical School, University of Sydney, Sydney, Australia
- Department of Dermatology, Royal North Shore Hospital, St Leonards, Australia
| | - Robert Sinclair
- Queensland Institute of Dermatology, Brisbane, Australia
- Specialist Connect Services, Brisbane, Australia
| | - Walter J. Curran
- Oncology, GenesisCare, Fort Myers, FL, USA
- Emory University, Atlanta, GA, USA
| | - David Christie
- GenesisCare, Gold Coast, QLD, Australia
- School of Medicine, Bond University, Gold Coast, QLD, Australia
| | - Bradley Wong
- GenesisCare Radiation Oncology, Buderim, QLD, Australia
| | - Peter Foley
- Department of Dermatology, St Vincent’s Hospital Melbourne, Fitzroy, Australia
- Department of Medicine, The University Melbourne, Melbourne, Australia
- Probity Medical Research, Skin Health Institute, Melbourne, Australia
| | - Peter O’Brien
- GenesisCare Radiation Oncology, Newcastle, NSW, Australia
| | - Lynda Spelman
- Queensland Institute of Dermatology, Brisbane, Australia
- Specialist Connect Services, Brisbane, Australia
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Devlin EJ, Whitford HS, Denson LA, Potter AE. "Just As I Expected": A Longitudinal Cohort Study of the Impact of Response Expectancies on Side Effect Experiences During Radiotherapy for Prostate Cancer. J Pain Symptom Manage 2019; 57:273-281.e4. [PMID: 30447387 DOI: 10.1016/j.jpainsymman.2018.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 11/01/2018] [Accepted: 11/02/2018] [Indexed: 11/19/2022]
Abstract
CONTEXT Previous research has indicated that pretreatment response expectancies of side effects often predict subsequent toxicity severity. However, this has been largely based on female patients undergoing chemotherapy. OBJECTIVES We tested whether this association also occurred in a novel cohort, men with prostate cancer undergoing radiotherapy. We investigated these associations throughout treatment (before and after side effects were medically predicted to occur), controlling known and novel variables. METHODS Homogenous male patients scheduled for radiotherapy (N = 35, mean age 71 years) completed baseline (pretreatment) measures; response expectancies of 18 treatment-related side effects; questions about baseline health and hormonal treatment, emotional state, and coping style. Response expectancies of the side effects were again measured two weeks into treatment. The severity of the same 18 toxicities was assessed two and seven weeks into treatment. RESULTS Hierarchical multiple linear regressions revealed baseline response expectancies significantly and independently predicted six of 18 toxicities two weeks into radiotherapy, contributing 12%-30% of explained variance (β = 0.39-0.59). Response expectancies assessed two weeks into treatment significantly and uniquely predicted seven of 17 experienced toxicities at seven weeks, explaining 17%-50% of variance (β = 0.49-0.91). Sexual toxicity response expectancies revealed the strongest associations with experience throughout treatment (β = 0.46-0.91), with "inability to reach orgasm" showing the largest effect. CONCLUSION In this older male sample, response expectancies of side effects predicted experiences throughout treatment, including the period before toxicities were medically expected. Response expectancies of sexual side effects were robust, independent predictors of subsequent toxicities across treatment, especially issues with orgasm, warranting focus in practice and future research.
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Affiliation(s)
- Elise J Devlin
- School of Psychology, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia.
| | - Hayley S Whitford
- School of Psychology, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia; University of South Australia Cancer Research Institute, University of South Australia, Adelaide, South Australia, Australia
| | - Linley A Denson
- School of Psychology, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia
| | - Andrew E Potter
- GenesisCare Radiation Oncology South Australia, Adelaide, South Australia, Australia
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Roos DE, Patel SG, Potter AE, Zacest AC. When is an acoustic neuroma not an acoustic neuroma? Pitfalls for radiosurgeons. J Med Imaging Radiat Oncol 2015; 59:474-479. [PMID: 26041515 DOI: 10.1111/1754-9485.12328] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2014] [Accepted: 04/27/2015] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Because acoustic neuroma (AN), also termed vestibular schwannoma, constitutes by far the commonest intracranial schwannoma and cerebello-pontine angle (CPA) tumour, there is a risk of overlooking rarer alternative diagnoses with similar clinical and/or radiological features. The purpose of this article is to highlight to radiosurgeons the potentially serious implications of this problem through illustrative case studies. METHODS Our linac stereotactic radiosurgery (SRS) technique has been previously described, with stereotactic headring fixation and treatment delivered via cones or micro-multileaf collimators using multiple arcs or static beams. RESULTS Between November 1993 and October 2014, we treated 132 patients referred with a clinical diagnosis of AN, the vast majority with 12 Gy marginal dose. Three of these (2.3%), evident either at the time of treatment (2) or subsequently (1), had features instead consistent with cochlear schwannoma, facial schwannoma and meningioma, respectively. Each warranted significant modification to standard AN outlining and fields. The meningioma progressed due to geographic miss. One other patient with recurrent facial schwannoma (not yet needing SRS) was also referred with an incorrect diagnosis of AN. CONCLUSION When rare variants of common medical problems are not identified before referral, there is a risk that 'blinkering' can lead to misdiagnosis and suboptimal treatment. Radiosurgeons need to be particularly mindful of this issue with AN, which can mimic several other tumours occurring in the CPA region, albeit with different patterns of spread. Optimal imaging, high-quality radiology reporting and neuroradiology input at the time of SRS planning within the setting of a specialised multidisciplinary team are highly desirable.
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Affiliation(s)
- Daniel E Roos
- Department of Radiation Oncology, Royal Adelaide Hospital, Adelaide, South Australia, Australia.,School of Medicine, University of Adelaide, Adelaide, South Australia, Australia
| | - Sandy G Patel
- Department of Radiology, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Andrew E Potter
- Department of Radiation Oncology, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Andrew C Zacest
- Department of Neurosurgery, Royal Adelaide Hospital, Adelaide, South Australia, Australia.,School of Surgery, University of Adelaide, Adelaide, South Australia, Australia
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Zacest AC, Caon J, Roos DE, Potter AE, Sullivan T. LINAC radiosurgery for cerebral arteriovenous malformations: a single centre prospective analysis and review of the literature. J Clin Neurosci 2013; 21:241-5. [PMID: 24148692 DOI: 10.1016/j.jocn.2013.03.040] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2013] [Revised: 03/27/2013] [Accepted: 03/30/2013] [Indexed: 11/24/2022]
Abstract
Stereotactic radiosurgery (SRS) is a well established, minimally invasive treatment option for patients diagnosed with cerebral arteriovenous malformations (AVM). We present the experience in linear accelerator-based SRS for cerebral AVM treated over 14 years. We prospectively followed 67 patients with 69 AVM treated with SRS from 1994 to 2008, inclusive. The mean patient age was 37 years (range 7-69) with 36 women and 31 men. The median AVM size, as defined by maximal diameter, was 2.5 cm (range 0.5-4.6 cm) and the median marginal dose was 18 Gy in one fraction. The crude angiographic obliteration rate was 55% with a 3 and 5 year actuarial rate of 39% and 65%, respectively. Median time to obliteration was 4.2 years. Higher treatment dose (p<0.0001) and smaller maximal AVM diameter (p=0.002) were associated with an increased obliteration rate. There were no deaths from treatment. Post-treatment neurological complications occurred in 10 patients (15%) including hemorrhage in two. Twelve patients (18%) required a second SRS procedure. Larger AVM diameter was associated with increased odds of requiring re-treatment (p=0.02). Radiosurgery for intracerebral AVM is a non-invasive therapeutic option with low morbidity and a reasonable likelihood of nidus obliteration. Treatment dose and AVM diameter are the main determinants of obliteration.
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Affiliation(s)
- Andrew C Zacest
- Department of Neurosurgery, Royal Adelaide Hospital, North Terrace, Adelaide, SA 5000, Australia; Discipline of Surgery, University of Adelaide, Adelaide, SA, Australia.
| | - Julianna Caon
- Department of Radiation Oncology, Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Daniel E Roos
- Department of Radiation Oncology, Royal Adelaide Hospital, Adelaide, SA, Australia; Discipline of Medicine, University of Adelaide, Adelaide, SA, Australia
| | - Andrew E Potter
- Department of Radiation Oncology, Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Thomas Sullivan
- Discipline of Public Health, University of Adelaide, Adelaide, SA, Australia
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Adams G, Martin OA, Roos DE, Lobachevsky PN, Potter AE, Zacest AC, Bezak E, Bonner WM, Martin RF, Leong T. Enhanced intrinsic radiosensitivity after treatment with stereotactic radiosurgery for an acoustic neuroma. Radiother Oncol 2012; 103:410-4. [PMID: 22560711 PMCID: PMC7418889 DOI: 10.1016/j.radonc.2012.03.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Revised: 03/23/2012] [Accepted: 03/26/2012] [Indexed: 02/01/2023]
Abstract
Enhanced radiosensitivity is an uncommon phenomenon attributable to deficient DNA repair after radiotherapy which can be assessed with the γ-H2AX assay. Reports of radiosensitivity after stereotactic radiosurgery (SRS) are uncommon. We describe a case where the clinical, radiological and laboratory findings suggest enhanced radiosensitivity after SRS for an acoustic neuroma.
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Affiliation(s)
- Gerard Adams
- Department of Radiation Oncology, Royal Adelaide Hospital, North Terrace, Adelaide, South Australia 5000, Australia.
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Roos DE, Potter AE, Zacest AC. Hearing preservation after low dose linac radiosurgery for acoustic neuroma depends on initial hearing and time. Radiother Oncol 2011; 101:420-4. [DOI: 10.1016/j.radonc.2011.06.035] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Revised: 06/15/2011] [Accepted: 06/15/2011] [Indexed: 10/18/2022]
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Roos DE, Potter AE, Brophy BP. Stereotactic radiosurgery for acoustic neuromas: what happens long term? Int J Radiat Oncol Biol Phys 2011; 82:1352-5. [PMID: 21700400 DOI: 10.1016/j.ijrobp.2011.04.068] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Revised: 04/19/2011] [Accepted: 04/29/2011] [Indexed: 10/18/2022]
Abstract
PURPOSE To determine the clinical outcomes for acoustic neuroma treated with low-dose linear accelerator stereotactic radiosurgery (SRS) >10 years earlier at the Royal Adelaide Hospital using data collected prospectively at a dedicated SRS clinic. METHODS AND MATERIALS Between November 1993 and December 2000, 51 patients underwent SRS for acoustic neuroma. For the 44 patients with primary SRS for sporadic (unilateral) lesions, the median age was 63 years, the median of the maximal tumor diameter was 21 mm (range, 11-34), and the marginal dose was 14 Gy for the first 4 patients and 12 Gy for the other 40. RESULTS The crude tumor control rate was 97.7% (1 patient required salvage surgery for progression at 9.75 years). Only 8 (29%) of 28 patients ultimately retained useful hearing (interaural pure tone average ≤50 dB). Also, although the Kaplan-Meier estimated rate of hearing preservation at 5 years was 57% (95% confidence interval, 38-74%), this decreased to 24% (95% confidence interval, 11-44%) at 10 years. New or worsened V and VII cranial neuropathy occurred in 11% and 2% of patients, respectively; all cases were transient. No case of radiation oncogenesis developed. CONCLUSIONS The long-term follow-up data of low-dose (12-14 Gy) linear accelerator SRS for acoustic neuroma have confirmed excellent tumor control and acceptable cranial neuropathy rates but a continual decrease in hearing preservation out to ≥10 years.
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Affiliation(s)
- Daniel E Roos
- Department of Radiation Oncology, Royal Adelaide Hospital, Adelaide, South Australia, Australia.
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Geake J, Potter AE, Borg MF, Lipsett J, Koukourou A. Stage I seminoma in a 15-year-old boy. ACTA ACUST UNITED AC 2007; 51:99-102. [PMID: 17217500 DOI: 10.1111/j.1440-1673.2006.01670.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Seminomas are very rare tumours in children and adolescents. We describe a case of seminoma in a 15-year-old boy who was managed with orchidectomy but no adjuvant therapy. He remains relapse-free 8 years after surgery as determined by clinical, radiological and serological surveillance. This study emphasizes the uncertainty over the need for adjuvant treatment in the management of seminoma in the adolescent patient, in particular in prepubescent children.
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Affiliation(s)
- J Geake
- Department of Radiation Oncology, Woman's and Children's Hospital, Adelaide, South Australia, Australia
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Abstract
Glomus tumours are uncommon neoplasms. Very rarely do they present in the paediatric age group. We describe a case of bilateral glomus tumours in a 13-year-old girl that were successfully treated with radiotherapy. The patient remains well 8 years after completion of treatment.
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Affiliation(s)
- K A S Lim
- Department of Radiation Oncology, Royal Adelaide Hospital, North Terrace, Adelaide, South Australia 5000, Australia
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Haynes DR, Crotti TN, Potter AE, Loric M, Atkins GJ, Howie DW, Findlay DM. The osteoclastogenic molecules RANKL and RANK are associated with periprosthetic osteolysis. J Bone Joint Surg Br 2001; 83:902-11. [PMID: 11521937 DOI: 10.1302/0301-620x.83b6.10905] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Extensive osteolysis adjacent to implants is often associated with wear particles of prosthetic material. We have investigated if RANKL, also known as osteoprotegerin ligand, osteoclast differentiation factor or TRANCE, and its natural inhibitor, osteoprotegerin (OPG), may be important in controlling this bone loss. Cells isolated from periprosthetic tissues containing wear particles expressed mRNA encoding for the pro-osteoclastogenic molecules, RANKL, its receptor RANK, monocyte colony-stimulating factor (M-CSF), interleukin (IL)-1beta, tumour necrosis factor (TNF)alpha, IL-6, and soluble IL-6 receptor, as well as OPG. Osteoclasts formed from cells isolated from periprosthetic tissues in the presence and absence of human osteoblastic cells. When osteoclasts formed in the absence of osteoblastic cells, markedly higher levels of RANKL mRNA relative to OPG mRNA were expressed. Particles of prosthetic materials also stimulated human monocytes to express osteoclastogenic molecules in vitro. Our results suggest that ingestion of prosthetic wear particles by macrophages results in expression of osteoclast-differentiating molecules and the stimulation of macrophage differentiation into osteoclasts.
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Affiliation(s)
- D R Haynes
- Department of Pathology, University of Adelaide, South Australia, Australia
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Kitchener PD, Dziegielewska KM, Knott GW, Miller JM, Nawratil P, Potter AE, Saunders NR. Fetuin expression in the dorsal root ganglia and trigeminal ganglia of perinatal rats. Int J Dev Neurosci 1997; 15:717-27. [PMID: 9402222 DOI: 10.1016/s0736-5748(97)00030-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Fetuin, a fetal plasma glycoprotein, has been shown previously to be present in sub-populations of neurons in the developing central and peripheral nervous system. To gain a more complete description of the time course of the appearance of fetuin during neurogenesis we have examined fetuin immunoreactivity, and the presence of fetuin mRNA, in the developing rat trigeminal and dorsal root ganglia. Fetuin immunoreactivity and its mRNA were first seen at embryonic day 15 in the trigeminal ganglia, and at embryonic day 16 in dorsal root ganglia. In both trigeminal and dorsal root ganglion, fetuin appeared to be present up until around the time of birth, and then again between postnatal days 3 and 16. The results suggest that fetuin first appears at around the time that ganglion cell axons reach their central targets, which is also approximately when the cell-death period begins. The proportion of ganglion neurons that were fetuin immunoreactive at different ages was inversely related to the amount of cell death that is known to occur in these populations, thus it seems that fetuin is more likely to be associated not with dying cells, but with those that survive the cell-death period.
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Affiliation(s)
- P D Kitchener
- Department of Anatomy and Physiology, University of Tasmania, Hobart, Australia
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Abstract
A measure assessing the roles played by children in their alcoholic families is presented. In Study 1, an item pool was generated targeting four distinct roles discussed in the alcohol literature, and the items were reviewed by a panel of experts. The Children's Roles Inventory (CRI) was then administered to 140 adult children of alcoholics and their responses were used to refine the measure. Observed levels of internal consistency seemed adequate (Cronbach's alpha ranged from .89 to .95). In a replication effort (Study 2), the CRI was administered to 142 adult children of alcoholics. Internal consistency remained at acceptable levels, ranging from .90 to .95. Study 3 examined the CRI's convergent and discriminant validity. A sample of 138 adult children of alcoholics as well as a sample of 105 adults from nonalcoholic families completed the CRI, a measure of self-esteem and an index of one's use of social support. Reliability results from Studies 1 and 2 were replicated (in both samples). Likewise, in both samples the CRI subscales were differentially predictive of self-esteem as well as size of and satisfaction with one's social support network.
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Affiliation(s)
- A E Potter
- Department of Educational Psychology, University of Nebraska-Lincoln 68588
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Abstract
Monochromatic images of Mercury at the sodium D(2) emission line showed excess sodium emission in localized regions at high northern and southern latitudes and day-to-day global variations in the distribution of sodium emission. These phenomena support the suggestion that magnetospheric effects could be the cause. Sputtering of surface minerals could produce sodium vapor in polar regions during magnetic substorms, when magnetospheric ions directly impact the surface. Another important process may be the transport of sodium ions along magnetic field lines toward polar regions, where they impact directly on the surface of Mercury and are neutralized to regenerate neutral sodium atoms. Day-to-day variations in planetary sodium distributions could result from changing solar activity, which can change the magnetosphere in time scales of a few hours. Observations of the sodium exosphere may provide a tool for remote monitoring of the magnetosphere of Mercury.
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Abstract
Spectra of the region just above the bright limb of the Moon show weak emission features that are attributed to resonant scattering of sunlight from sodium and potassium vapor in the lunar atmosphere. The maximum omnidirectional emission flux above the bright limb is 3.8 +/- 0.4 kilorayleighs for sodium and 1.8 +/- 0.4 kiloray-leighs for potassium. The zenith column densities above the subsolar point are estimated to be 8 +/- 3 x 10(8) atoms cm(-2) for sodium 1.4 +/- 0.3 x 10(8) atoms cm(-2) for potassium. Corresponding surface densities are 67 +/- 12 atoms cm(-3) and 15 +/- 3 atoms cm(-3), respectively. The scale height for the sodium atmosphere is 120 +/- 42 kilometers, and for potassium 90 +/- 20 kilometers, which implies that the effective temperature of the sodium and potassium is close to the lunar surface temperature. The sodium density at the south polar region was found to be similar to that at the subsolar point, indicating wide-spread distribution of sodium vapor over the lunar surface. The ratio of the density of sodium to the density of potassium is (6 +/- 3) to 1, which is close to the sodium to potassium ratio in the lunar surface, suggesting that the atmosphere originates from the vaporization of surface minerals.
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Abstract
The relationship between correction of hyponatraemia and the development of central pontine myelinolysis (CPM) remains controversial. A case of CPM associated with extensive extrapontine demyelination is described. Profound hyponatraemia and its subsequent correction are documented. It is suggested that the extent of demyelination reflects the degree of hyponatraemia noted prior to correction, supporting current hypotheses regarding the role of hyponatraemia in CPM. This case is unusual in that other recognized risk factors for the development of CPM are absent.
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Abstract
The reaction of vibrationally excited hydroxyl with ozone was studied in a fast-flow system by observing the effect of ozone concentration on the intensity of hydroxyl emission bands in the 1.4-micro to 2.2-micro wavelength region. Fourier transform spectroscopy was used to obtain spectra of the faint emissions from the excited hydroxyl. Rate constants for the ozone-hydroxyl reaction were calculated for vibrational levels nu = 2 to nu = 9. The rate constants increased with vibrational level in a regular manner up to nu = 5. An abrupt increase occurred for nu = 6 relative to nu = 5, which may suggest a change in mechanism beginning at nu = 6.
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Abstract
A mass-spectrometric stirred-reactor technique was used to study the reaction of atomic oxygen with methane with low concentrations of molecular oxygen. An overall rate constant for oxygen-atom disappearance due to added methane was obtained for the temperature range 375 to 576°K. This rate constant was 4 × 1014 exp (− 10 000/RT) cm3 mole−1 s−1 and was compared with a previous rate constant for this reaction that had been measured in the presence of a large excess of molecular oxygen. This comparison showed that the presence of an excess of molecular oxygen produced a considerable increase in oxygen-atom consumption at low temperatures, but only a small increase at high temperatures. From product analyses, the stoichiometry of the reaction could be approximately represented by [Formula: see text]From the reaction stoichiometry and the rate constant for the oxygen-atom disappearance, the rate constant for methane disappearance was calculated to be 1 × 1014 exp (− 10 000/RT) cm3 mole−1 s−1. The presence of excess molecular oxygen has very little effect on this rate constant, contrary to the result found for the disappearance of atomic oxygen.
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