scholarly journals Particles in Jupiter's atmosphere from the impacts of Comet P/Shoemaker-Levy 9

1996 ◽  
Vol 156 ◽  
pp. 269-292
Author(s):  
Robert A. West
Keyword(s):  
Hubble Space Telescope ◽  
Spectral Feature ◽  
Particle Volume ◽  
Dark Clouds ◽  
Cometary Material ◽  
Infrared Wavelengths ◽  
The Mean ◽  
One Year ◽  
The Impact ◽  
Volatile Materials

The dark clouds that were easily seen in small telescopes after the comet impacts were caused by small particles which were deposited in Jupiter's stratosphere. Observations from the Hubble Space Telescope and from ground-based instruments at visible and infrared wavelengths indicate that the mean radius of the particles is in the range 0.1 to 0.3 μm, and the total volume of particles is approximately the same as that for a 1-km diameter sphere. In the dark core regions of freshly-formed impacts, the particles are distributed over a large vertical extent, between about 1 mb and 200 mb or deeper. The diffuse outlying haze is confined to the high-altitude end of the range. Such a distribution probably reflects different methods of emplacement of the debris as a function of distance from the impact. The color of the particles, and their volatility as required to make waves visible, suggest an organic material as the main constituent. These relatively volatile materials are thought to have condensed onto more refractory grains after the plume material cooled, some 30 minutes or more after impact. The most refractory materials expected to condense from an evolving fireball are Al2O3, magnesium and iron silicates, and soot, depending on the C/O ratio. A silicate spectral feature was observed, confirming that cometary material was incorporated into the grains, although silicate grains make up only 10-20% of the particle volume. After one year in Jupiter's stratosphere, the particles have spread some 20° in latitude and a significant number have sedimented into the troposphere where they are no longer visible.

scholarly journals Earth-based observations of impact phenomena

1996 ◽  
Vol 156 ◽  
pp. 81-109
Author(s):  
Philip D. Nicholson
Keyword(s):  
Hubble Space Telescope ◽  
Common Pattern ◽  
Mid Infrared ◽  
Wide Range ◽  
Impact Phenomena ◽  
Infrared Wavelengths ◽  
Positive Correlations ◽  
The Individual ◽  
The Impact ◽  
Size Estimates

Earth-based observations at near- and mid-infrared wavelengths were obtained for at least 15 of the SL9 impacts, ranging from the spectacular G, K and L events to the barely-detected N and V impacts. Although there were a few exceptions, most of the IR lightcurves fit a common pattern of one or two relatively faint precursor flashes, followed several minutes later by the main infrared event as the explosively-ejected plume crashed down onto the jovian atmosphere. Correlations with the impact times recorded by the Galileo spacecraft and plumes imaged by the Hubble Space Telescope lead to an interpretation of the twin precursors in terms of (i) the entry of the bolide into the upper atmosphere, and (ii) the re-appearance of the rising fireball above Jupiter's limb. Positive correlations are observed between the peak IR flux observed during the splashback phase and both pre-impact size estimates for the individual SL9 fragments and the scale of the resulting ejecta deposits. None of the fragments observed to have moved off the main train of the comet by May 1994 produced a significant impact signature. Earth-based fireball temperature estimates are on the order of 750 K, 30-60 sec after impact. For the larger impacts, the unexpectedly protracted fireball emission at 2.3 μm remains unexplained. A wide range of temperatures has been inferred for the splashback phase, where shocks are expected to have heated the re-entering plume material at least briefly to several thousand K, and further modelling is required to reconcile these data.

The impact of a breast cancer diagnosis on women’s work status.

2018 ◽  
Vol 36 (7_suppl) ◽  
pp. 23-23
Author(s):  
Lucinda Barry ◽  
Leanne Storer ◽  
Meron Pitcher
Keyword(s):  
Breast Cancer ◽  
Cancer Diagnosis ◽  
Financial Stress ◽  
Breast Cancer Diagnosis ◽  
Work Status ◽  
Paid Employment ◽  
The Mean ◽  
Woman's Work ◽  
One Year ◽  
The Impact

23 Background: The diagnosis and treatment of cancer often causes financial stress, partly by impacting on the ability to continue in paid employment. Our aim was to identify changes in work status 12 months after a diagnosis of breast cancer. Methods: An audit of the medical records of women who presented to the Western Health (Victoria, Australia) nurse led breast cancer Survivorship Clinic (SC) between October 2015 and October 2016 was performed to identify employment status at diagnosis and at their review at SC 12 months later. Results: 111 records were reviewed. The mean age was 55 (range 28-82yrs). 84 of these women (76%) were 65 years of younger at the time of diagnosis. 46 of the 84 women ≤65 years were in paid employment at diagnosis (55%), and 38 (83%) were still working in some capacity at review in the SC. Of the 38 still working, 28 were working in the same capacity, 8 were working reduced hours, and 2 were working increased hours. Women who had axillary dissections were most likely to have changed work status. Financial stress was reported by 8/19 of women who stopped working or had changed work hours, including 9 no longer in paid employment and 10 with changed hours. 2/28 women working in the same capacity reported financial stress. 65% of those who reported financial stress (11/17) had chemotherapy as part of their treatment. Conclusions: A breast cancer diagnosis has the ability to influence a woman's work status one year after diagnosis. Health professionals should appreciate the potential work concerns and financial stresses continuing to affect their patients.

scholarly journals Sinus heart rate post pulmonary vein ablation and long-term risk of recurrences

2020 ◽  
Author(s):  
Gesa von Olshausen ◽  
Ott Saluveer ◽  
Jonas Schwieler ◽  
Nikola Drca ◽  
Hamid Bastani ◽  
...  
Keyword(s):  
Heart Rate ◽  
Pulmonary Vein ◽  
Heart Rate Change ◽  
Rate Change ◽  
Study Cohort ◽  
The Mean ◽  
One Year ◽  
The One ◽  
The Impact

Abstract Purpose Cather ablation is known to influence the autonomic nervous system. This study sought to investigate the association of sinus heart rate pre-/post-ablation and recurrences in patients with atrial fibrillation undergoing pulmonary vein isolation (PVI). Methods Between January 2012 and December 2017, data of 482 patients undergoing their first PVI were included. Sinus heart rate was recorded before (PRE), directly post-ablation (POST) and 3 months post-ablation (3 M). All patients were screened for atrial tachyarrhythmia recurrences during the one-year follow-up. Results In the total study cohort, the mean resting sinus heart rate at PRE [mean 57.9 bpm (95% CI 57.1–58.7 bpm)] increased by over 10 bpm to POST [mean 69.4 bpm (95% CI 68.5–70.3 bpm); p < 0.001] followed by a slight decrease at 3 M [mean 67.3 bpm (95% CI 66.4–68.2 bpm)] but still remaining higher compared to PRE (p < 0.001). This pattern was observed in patients with and without recurrences at POST and 3 M (both p < 0.001 compared to PRE). However, at 3 M the mean sinus heart rate was significantly lower in patients with compared to patients without recurrences (p = 0.031). In this regard, patients with a heart rate change < 11 bpm (PRE to 3 M) or, as an alternative parameter, patients with a heart rate < 60 bpm at 3 M had a significantly higher risk of recurrences compared to the remaining patients (Hazard ratio (HR) 1.82 (95% CI 1.32–2.49), p < 0.001 and HR 1.64 (95% CI 1.20–2.25), p = 0.002, respectively). Conclusion Our study confirms the impact of PVI on cardiac autonomic function with a significant sinus heart rate increase post-ablation. Patients with a sinus heart rate change < 11 bpm (PRE to 3 M) are at higher risk for recurrences during one-year post-PVI.

scholarly journals The impact of tube replacement timing during LCIG therapy on PEG-J associated adverse events: a retrospective multicenter observational study

2021 ◽  
Author(s):  
Kanefumi Yamashita ◽  
Yukinori Yube ◽  
Yukinao Yamazaki ◽  
Takehide Fukuchi ◽  
Masaki Kato ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Adverse Events ◽  
Advanced Parkinson’S Disease ◽  
Multicenter Observational Study ◽  
Exchange Time ◽  
Tube Exchange ◽  
The Mean ◽  
One Year ◽  
The Impact

Abstract Background Levodopa–carbidopa intestinal gel (LCIG) treatment, a new drug delivery system for patients with advanced Parkinson’s disease (PD), is covered by the health insurance in Japan since September 2016. Various LCIG procedure/device-associated adverse events (AEs) have been reported; however, reports on their treatment have been limited. This is the first multicenter study to clarify the frequency and timing of device-related AEs. Methods Between September 2016 and December 2018, 104 patients introduced to the LCIG treatment for advanced PD in 11 hospitals were included. The patients’ characteristics, AEs incidence, AEs time, and tube exchange time were investigated. Results The median follow-up period was 21.5 months. Minor AE cases were 29.4%, whereas major AE cases were 43.1%. Majority of major AEs (n = 55, 96.5%) were managed with endoscopic treatment, such as tube exchange. Few severe AEs required surgical treatment (n = 2, 3.5%). The mean (range) exposure to percutaneous endoscopic gastrojejunostomy (PEG-J) was 14.7 (0–33) months. One year after the LCIG treatment introduction, 55 patients (54.0%) retained the original PEG-J tube. The mean PEG-J tube exchange time was 10.8 ± 7.0 months in all patients, 11.6 ± 4.7 and 10.5 ± 7.7 months in patients with scheduled exchange and who underwent exchange due to AEs, respectively. Conclusions Some device-related AEs occurred during the LCIG treatment; however, only few were serious, most of which could be treated with simple procedures or tube replacement with endoscopy. Therefore, the LCIG treatment is feasible and safe and is a unique treatment option for PD, requiring endoscopists’ understanding and cooperation.

scholarly journals The impact of tube replacement timing during LCIG therapy on PEG-J associated adverse events: a retrospective multicenter observational study

BMC Neurology ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Kanefumi Yamashita ◽  
Yukinori Yube ◽  
Yukinao Yamazaki ◽  
Takehide Fukuchi ◽  
Masaki Kato ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Adverse Events ◽  
Advanced Parkinson’S Disease ◽  
Multicenter Observational Study ◽  
Exchange Time ◽  
Tube Exchange ◽  
The Mean ◽  
One Year ◽  
The Impact

Abstract Background Levodopa–carbidopa intestinal gel (LCIG) treatment, a unique drug delivery system for patients with advanced Parkinson’s disease (PD), is covered by health insurance in Japan since September 2016. Various LCIG procedure/device-associated adverse events (AEs) have been reported; however, reports on their treatment have been limited. This is the first multicenter study to clarify the frequency and timing of device-related AEs. Methods Between September 2016 and December 2018, 104 patients introduced to the LCIG treatment for advanced PD in 11 hospitals were included. The patients’ characteristics, AEs incidence, AEs time, and tube exchange time were investigated. Results The median follow-up period was 21.5 months. Minor AE cases were 29.4%, whereas major AE cases were 43.1%. Majority of major AEs (n = 55, 94.8%) were managed with endoscopic treatment, such as tube exchange. Few severe AEs required surgical treatment (n =3, 5.2%). The mean (range) exposure to percutaneous endoscopic gastrojejunostomy (PEG-J) was 14.7 (0–33) months. One year after the LCIG treatment introduction, 55 patients (54.0%) retained the original PEG-J tube. The mean PEG-J tube exchange time was 10.8 ± 7.0 months in all patients, 11.6 ± 4.7 and 10.5 ± 7.7 months in patients with scheduled exchange and who underwent exchange due to AEs, respectively. Conclusions Some device-related AEs occurred during the LCIG treatment; however, only few were serious, most of which could be treated with simple procedures or tube replacement with endoscopy. Therefore, the LCIG treatment is feasible and safe and is a unique treatment option for PD, requiring endoscopists’ understanding and cooperation.

scholarly journals A Train-the-Trainers (TtT) Program for Engineers for Hosting Multiparty International Clinical Teleconferences

2019 ◽  
Vol 7 ◽  
Author(s):  
Kuriko Kudo ◽  
Tomohiko Moriyama ◽  
Shunta Tomimatsu ◽  
Shintaro Ueda ◽  
Shuji Shimizu
Keyword(s):  
Medical Care ◽  
Training Period ◽  
Train The Trainer ◽  
Hands On ◽  
The Mean ◽  
One Year ◽  
The Impact

Background: International clinical teleconferencing connecting hospitals contributes to the standardisation of medical care. Introduction: The perception that participating in international teleconferences is easy while hosting and coordinating them is difficult has limited the expansion of these kinds of programmes. We evaluated the effectiveness of a Train-the-Trainer (TtT) programme on hosting international multiparty teleconferences targeted at hospital engineers. Methods: From 2015 to 2017, 20 engineers and physicians from 17 institutions in 10 countries participated in Kyushu University Hospital’s TtT programme. Hands-on training and hosting a Training Report Conference (TRC) were conducted. The impact of the programme was assessed using questionnaires about the participants’ confidence, perception of barriers, and teleconference activity before and one year after the training period. Results: The mean training period was 16.7 days (median, 19 days). Twelve TRCs were hosted by trainees connecting 56 institutions in 11 countries. All participants gave positive evaluations of the overall programme, 19 (95%) "very good" and 1 (5%) "good", and the trainers 9 (90%) "very good" and 1 (10%) "good"). Following the TtT programme, the mean number of trainee-hosted events increased significantly (0.8 to 1.3, p<0.001), and more respondents (12/17, 71%) reported barriers to hosting a programme than participating in one (5/17, 29%, p<0.001). Trainee confidence in both hosting and participating in international teleconferences was significantly higher after TtT. Conclusion: There are more barriers to hosting than participating in international clinical teleconferences. This TtT programmes for engineers could contribute to more active hosting engagement.

Asteroid and Comet Impact Speeds upon Mars: Significance for Panspermia and the Supply of Organics

1997 ◽  
Vol 161 ◽  
pp. 197-201 ◽  
Author(s):  
Duncan Steel
Keyword(s):  
Probability Distributions ◽  
Regions Of Interest ◽  
Significant Fraction ◽  
Organic Chemicals ◽  
Impact Speed ◽  
The Mean ◽  
The Impact

AbstractWhilst lithopanspermia depends upon massive impacts occurring at a speed above some limit, the intact delivery of organic chemicals or other volatiles to a planet requires the impact speed to be below some other limit such that a significant fraction of that material escapes destruction. Thus the two opposite ends of the impact speed distributions are the regions of interest in the bioastronomical context, whereas much modelling work on impacts delivers, or makes use of, only the mean speed. Here the probability distributions of impact speeds upon Mars are calculated for (i) the orbital distribution of known asteroids; and (ii) the expected distribution of near-parabolic cometary orbits. It is found that cometary impacts are far more likely to eject rocks from Mars (over 99 percent of the cometary impacts are at speeds above 20 km/sec, but at most 5 percent of the asteroidal impacts); paradoxically, the objects impacting at speeds low enough to make organic/volatile survival possible (the asteroids) are those which are depleted in such species.

Sound Production Treatment for Acquired Apraxia of Speech: An Examination of Dosage in Relation to Probe Performance

2020 ◽  
pp. 1-16
Author(s):  
Julie L. Wambaugh ◽  
Lydia Kallhoff ◽  
Christina Nessler
Keyword(s):  
Retrospective Analysis ◽  
Sound Production ◽  
Apraxia Of Speech ◽  
Practice Schedule ◽  
Practice Schedules ◽  
Baseline Performance ◽  
The Mean ◽  
Number Of Treatment ◽  
The Impact

Purpose This study was designed to examine the association of dosage and effects of Sound Production Treatment (SPT) for acquired apraxia of speech. Method Treatment logs and probe data from 20 speakers with apraxia of speech and aphasia were submitted to a retrospective analysis. The number of treatment sessions and teaching episodes was examined relative to (a) change in articulation accuracy above baseline performance, (b) mastery of production, and (c) maintenance. The impact of practice schedule (SPT-Blocked vs. SPT-Random) was also examined. Results The average number of treatment sessions conducted prior to change was 5.4 for SPT-Blocked and 3.9 for SPT-Random. The mean number of teaching episodes preceding change was 334 for SPT-Blocked and 179 for SPT-Random. Mastery occurred within an average of 13.7 sessions (1,252 teaching episodes) and 12.4 sessions (1,082 teaching episodes) for SPT-Blocked and SPT-Random, respectively. Comparisons of dosage metric values across practice schedules did not reveal substantial differences. Significant negative correlations were found between follow-up probe performance and the dosage metrics. Conclusions Only a few treatment sessions were needed to achieve initial positive changes in articulation, with mastery occurring within 12–14 sessions for the majority of participants. Earlier occurrence of change or mastery was associated with better follow-up performance. Supplemental Material https://doi.org/10.23641/asha.12592190

Impact of changing rainfall conditions on surface and groundwater resources in an experimental watershed in Greece

2013 ◽  
Vol 12 (2) ◽  
pp. 119-125
Keyword(s):  
Groundwater Resources ◽  
Annual Runoff ◽  
Annual Rainfall ◽  
Rainfall Regime ◽  
Winter Rainfall ◽  
Rainfall Depth ◽  
Rainfall Volume ◽  
The Mean ◽  
Groundwater Reserves ◽  
The Impact

The present study concerns the impact of a change in the rainfall regime on surface and groundwater resources in an experimental watershed. The research is conducted in a gauged mountainous watershed (15.18 km2) that is located on the eastern side of Penteli Mountain, in the prefecture of Attica, Greece and the study period concerns the years from 2003 to 2008. The decrease in the annual rainfall depth during the last two hydrological years 2006-2007, 2007-2008 is 10% and 35%, respectively, in relation to the average of the previous years. In addition, the monthly distribution of rainfall is characterized by a distinct decrease in winter rainfall volume. The field measurements show that this change in rainfall conditions has a direct impact on the surface runoff of the watershed, as well as on the groundwater reserves. The mean annual runoff in the last two hydrological years has decreased by 56% and 75% in relation to the average of the previous years. Moreover, the groundwater level follows a declining trend and has dropped significantly in the last two years.

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