Dissolved Oxygen Dynamics of a Stream: Model Discrimination and Estimation of Parameter Variability Using an Extended Kalman Filter

A model identification procedure is presented based on an extended Kaiman filter (EKF) applied to the oxygen mass balance equation of a stream. The procedure is used with data from a small Danish stream to discriminate among eight mathematical models of the photosynthesis-light (P-I) response of macrophytes in the stream. Each model was tested for adequacy using objective criteria based on the expected behavior of the innovations sequence (the time series of differences between predicted and observed oxygen concentrations) derived from the EKF. Temporal variation of the model parameters was also examined using the EKF. The maximum photosynthetic rate (Pm) varied slowly over the year but was essentially stationary within any three to six day period. The low light efficiency of photosynthesis (Eo) varied from day to day within any short period, but three to six day means of Eo were essentially stationary over the year. The ratio (Ik = Pm/Eo) was highly correlated with both short and long term variations in daily mean light intensity.

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High-energy environment of super-Earth 55 Cancri e

Astronomy and Astrophysics ◽

10.1051/0004-6361/201832700 ◽

2018 ◽

Vol 615 ◽

pp. A117 ◽

Cited By ~ 9

Author(s):

V. Bourrier ◽

D. Ehrenreich ◽

A. Lecavelier des Etangs ◽

T. Louden ◽

P. J. Wheatley ◽

...

Keyword(s):

Rest Frame ◽

High Energy ◽

X Ray ◽

Short Period ◽

Chromospheric Emission ◽

Energy Environment ◽

Short And Long Term ◽

Coronal Rain ◽

Far Ultraviolet

The high-energy X-ray to ultraviolet (XUV) irradiation of close-in planets by their host star influences their evolution and might be responsible for the existence of a population of ultra-short period planets eroded to their bare core. In orbit around a bright, nearby G-type star, the super-Earth 55 Cnc e offers the possibility to address these issues through transit observations at UV wavelengths. We used the Hubble Space Telescope to observe the transit in the far-ultraviolet (FUV) over three epochs in April 2016, January 2017, and February 2017. Together, these observations cover nearly half of the orbital trajectory in between the two quadratures, and reveal significant short- and long-term variability in 55 Cnc chromospheric emission lines. In the last two epochs, we detected a larger flux in the C III, Si III, and Si IV lines after the planet passed the approaching quadrature, followed by a flux decrease in the Si IV doublet. In the second epoch these variations are contemporaneous with flux decreases in the Si II and C II doublets. All epochs show flux decreases in the N V doublet as well, albeit at different orbital phases. These flux decreases are consistent with absorption from optically thin clouds of gas, are mostly localized at low and redshifted radial velocities in the star rest frame, and occur preferentially before and during the planet transit. These three points make it unlikely that the variations are purely stellar in origin, yet we show that the occulting material is also unlikely to originate from the planet. We thus tentatively propose that the motion of 55 Cnc e at the fringes of the stellar corona leads to the formation of a cool coronal rain. The inhomogeneity and temporal evolution of the stellar corona would be responsible for the differences between the three visits. Additional variations are detected in the C II doublet in the first epoch and in the O I triplet in all epochs with a different behavior that points toward intrinsic stellar variability. Further observations at FUV wavelengths are required to disentangle definitively between star-planet interactions in the 55 Cnc system and the activity of the star.

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Abstract 52: Short and Long Term Outcomes of Patients Admitted with Unexplained Syncope Using a Simple Novel SELF-Pathway

Circulation Cardiovascular Quality and Outcomes ◽

10.1161/circoutcomes.5.suppl_1.a52 ◽

2012 ◽

Vol 5 (suppl_1) ◽

Author(s):

Emad F Aziz ◽

Chaithanya K Pamidimukala ◽

Joseph H Bastawrose ◽

Terrence Park ◽

Balai Pratap ◽

...

Keyword(s):

Structural Heart Disease ◽

Common Disease ◽

Term Outcome ◽

Long Term Outcome ◽

Group I ◽

Short Period ◽

Short And Long Term ◽

Group Ii

Background: According to the design of our SELF pathway, patients are stratified twice using the acronyms SELF-A (Short period, Early-rapid onset, Loss of consciousness, Full recovery) and SELF-B (Structural heart disease, abnormal Ecg, and arrhythmia Fib/FL). We assessed the short and Long-term outcome according to this approach. Methods: 1468 patients were prospectively followed after presenting to our emergecy department for the evaluation of syncope. Patients were divided into Group I (SELF +/+) who met both SELF A and B criteria and group II (SELF -/-) who didnot meet these criteria.The primary endpoint was a composite of readmission for syncope, myocardial infarction (MI), stroke or death. Follow-up was 494 ± 120 days. Results: 644 (44%) patients were included in group I and 824 (64%) patients in group II. Group I were older (73 ± 15 years vs. 58 ± 22 years), with more evidence of hypertension (74% vs. 41%), diabetes (24% vs. 15%), heart failure (15% vs. 5%), and coronary disease (26% vs. 10%); p<0.001. During hospital stay group I underwent more procedures. At the end of 7, 30 and 180 days follow up, group I patients had 9 (2%), 33 (5%), 96 (15%) vs. 7 (0.8%), 19 (2%), 55 (6%) events respectively; p <0.001 (Figure). Conclusions: Using the SELF-pathway for patients presenting with syncope effectively identifies high risk patients who merit hospitalization for further work-up. This has important implications for the evaluation of a common disease that poses a significant economic burden on healthcare systems.

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Experience with Short and Long Term Courses of Local Adrenal Steroid Therapy For Ulcerative Colitis

Gastroenterology ◽

10.1016/s0016-5085(62)80117-6 ◽

1962 ◽

Vol 42 (6) ◽

pp. 669-677 ◽

Cited By ~ 18

Author(s):

Jean A. Spencer ◽

Joseph B. Kirsner

Keyword(s):

Ulcerative Colitis ◽

Steroid Therapy ◽

Adrenal Steroid ◽

Short And Long Term

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Short- and Long-Term Results of Total vs Subtotal Thyroid- ectomies in the Surgical Treatment of Graves' Disease

Swiss Surgery ◽

10.1024/1023-9332.7.1.20 ◽

2001 ◽

Vol 7 (1) ◽

pp. 20-24 ◽

Cited By ~ 14

Author(s):

Robert ◽

Mariéthoz ◽

Pache ◽

Bertin ◽

Caulfield ◽

...

Keyword(s):

Recurrent Laryngeal Nerve ◽

Nerve Palsy ◽

Recurrent Laryngeal Nerve Palsy ◽

Laryngeal Nerve ◽

Long Term Results ◽

Graves Disease ◽

Laryngeal Nerve Palsy ◽

Short And Long Term

Objective: Approximately one out of five patients with Graves' disease (GD) undergoes a thyroidectomy after a mean period of 18 months of medical treatment. This retrospective and non-randomized study from a teaching hospital compares short- and long-term results of total (TT) and subtotal thyroidectomies (ST) for this disease. Methods: From 1987 to 1997, 94 patients were operated for GD. Thirty-three patients underwent a TT (mostly since 1993) and 61 a ST (keeping 4 to 8 grams of thyroid tissue - mean 6 g). All patients had received propylthiouracil and/or neo-mercazole and were in a euthyroid state at the time of surgery; they also took potassium iodide (lugol) for ten days before surgery. Results: There were no deaths. Transient hypocalcemia (< 3 months) occurred in 32 patients (15 TT and 17 ST) and persistent hypocalcemia in 8 having had TT. Two patients developed transient recurrent laryngeal nerve palsy after ST (< 3 months). After a median follow-up period of seven years (1-15) with five patients lost to follow-up, 41 patients having had a ST are in a hypothyroid state (73%), thirteen are euthyroid (23%), and two suffered recurrent hyperthyroidism, requiring completion of thyroidectomy. All 33 patients having had TT - with follow-ups averaging two years (0.5-8) - are receiving thyroxin substitution. Conclusions: There were no instances of persistent recurrent laryngeal nerve palsy in either group, but persistent hypoparathyroidism occurred more frequently after TT. Long after ST, hypothyroidism developed in nearly three of four cases, whereas euthyroidy was maintained in only one-fourth; recurrent hyperthyroidy was rare.

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