scholarly journals Release timing and duration control the fate of photolytic compounds in stream-hyporheic systems

2021 ◽  
Author(s):  
Jase Hixson ◽  
Adam Ward ◽  
Christina Remucal ◽  
Megan McConville
Keyword(s):  
Release Timing

Tidal-amplitude rhythms of larval release: variable departure from presumed optimal timing among populations of the mottled shore crab

2010 ◽  
Vol 90 (5) ◽  
pp. 859-865 ◽  
Author(s):  
M. Bueno ◽  
A.A.V. Flores
Keyword(s):  
Comprehensive Evaluation ◽  
Natural Populations ◽  
Wave Action ◽  
Shore Crab ◽  
Optimal Timing ◽  
Rocky Shores ◽  
Tidal Amplitude ◽  
Larval Release ◽  
Underlying Mechanisms ◽  
Release Timing

It is widely assumed that optimal timing of larval release is of major importance to offspring survival, but the extent to which environmental factors entrain synchronous reproductive rhythms in natural populations is not well known. We sampled the broods of ovigerous females of the common shore crab Pachygrapsus transversus at both sheltered and exposed rocky shores interspersed along a 50-km coastline, during four different periods, to better assess inter-population differences of larval release timing and to test for the effect of wave action. Shore-specific patterns were consistent through time. Maximum release fell within 1 day around syzygies on all shores, which matched dates of maximum tidal amplitude. Within this very narrow range, populations at exposed shores anticipated hatching compared to those at sheltered areas, possibly due to mechanical stimulation by wave action. Average departures from syzygial release ranged consistently among shores from 2.4 to 3.3 days, but in this case we found no evidence for the effect of wave exposure. Therefore, processes varying at the scale of a few kilometres affect the precision of semilunar timing and may produce differences in the survival of recently hatched larvae. Understanding the underlying mechanisms causing departures from presumed optimal release timing is thus important for a more comprehensive evaluation of reproductive success of invertebrate populations.

3.5 SUPPRESSION OF SPRUCE BUDWORM POPULATIONS BY TRICHOGRAMMA MINUTUM RILEY, 1982–1986

1990 ◽  
Vol 122 (S153) ◽  
pp. 56-81 ◽  
Author(s):  
S.M. Smith ◽  
D.R. Wallace ◽  
G. Howse ◽  
J. Meating
Keyword(s):  
Choristoneura Fumiferana ◽  
Host Density ◽  
Spruce Budworm ◽  
Mass Rearing ◽  
Egg Parasitoid ◽  
Curvilinear Relationship ◽  
Egg Masses ◽  
Trichogramma Minutum ◽  
Egg Parasitism ◽  
Release Timing

AbstractThe ability of the egg parasitoid, Trichogramma minutum Riley, to suppress outbreak populations of the spruce budworm, Choristoneura fumiferana (Clemens), was studied annually near Hearst, Ont., from 1982 through 1986. Timing of broadcast parasitoid-releases was linked to spruce budworm moth emergence and oviposition. These phenological relationships were predicted from a regression based on larval development at least 2 weeks before expected emergence; this allowed sufficient time to regulate (program) parasitoid emergence during mass-rearing. Emergence of caged spruce budworm adults was used to monitor moth eclosion in the field. Pheromone traps provided daily information on the activity of male moths and helped to synchronize the parasitoid releases with spruce budworm oviposition. Information on parasitoid activity was obtained from sentinel (laboratory-reared) and naturally occurring spruce budworm egg masses. A curvilinear relationship between the rate of parasitoid release and parasitism of sentinel egg masses was developed. Two parasitoid releases, 1 week apart, early in the oviposition period of spruce budworm, significantly increased parasitism of host eggs by 14–83% and reduced larval populations correspondingly from 42 to 82%. Single releases were less effective and increased parasitism by 0.3–52% (single ground release, 1986). Two parasitoid releases, combined with a spring application of Bacillus thuringiensis Berliner to larval populations, was the most effective strategy and resulted in 83% egg parasitism and 93% larval reduction. Release rates greater than 12–16 × 106 ♀ ♀ T. minutum per hectare were not warranted based on impact and costs. The effects of release timing, weather, host density, and parasitoid quality on the future successful use of T. minutum are discussed.

Inverse modeling to estimate LNAPL plume release timing

2000 ◽  
Vol 45 (3-4) ◽  
pp. 303-327 ◽  
Author(s):  
J.C Parker ◽  
M Islam
Keyword(s):  
Inverse Modeling ◽  
Release Timing

Cardiovascular Biomarkers

2014 ◽  
Author(s):  
Parul U Gandhi ◽  
James L Januzzi Jr
Keyword(s):  
Myocardial Infarction ◽  
Natriuretic Peptide ◽  
Amino Terminal ◽  
Coronary Syndrome ◽  
Patients With Heart Failure ◽  
Troponin Release ◽  
Universal Definition ◽  
Definition Of ◽  
Release Timing ◽  
Cardiovascular Biomarkers

The value of circulating biomarkers to care for patients with cardiovascular disease has grown significantly over the last few decades. The majority of clinical data focus on the use of natriuretic peptides (NPs) for the diagnosis, prognosis, and management of patients with heart failure (HF) and troponin measurements in patients with suspected or proven acute coronary syndrome (ACS). Part of the reason for the slow adoption of biomarkers beyond these two classes has been limitation in the optimal modes of application of new assays. Future studies are needed to clarify the use of biomarkers, with the ultimate goal of simplifying the diagnosis, prognosis, and patient care of complex cardiovascular conditions. This chapter reviews the use of established biomarkers for HF, ACS, and atrial fibrillation (AF). Tables include a summary of emerging and established cardiovascular biomarkers, characteristics of B-type natriuretic peptide and amino-terminal pro-B-type natriuretic peptide, cutoff points for NP measurement, differential diagnosis of elevated NP concentrations, biomarkers in HF with preserved ejection fraction, summary of NP management trials, third universal definition of myocardial infarction, and guidelines for recommendations of biomarkers in HF. Figures depict the various causes of NP release, the complex mechanism of troponin release in patients with HF, the ischemic and nonischemic etiologies of troponin release, timing of biomarker release during myocardial infarction, and the biomarkers involved in the pathogenesis of AF. Algorithms demonstrate evaluating outpatients with dyspnea in the clinic using NPs in their workup and the use of troponin to assist with determining an appropriate management strategy for a patient with ACS. This review contains 7 highly rendered figures, 8 tables, and 202 references.

Cardiovascular Biomarkers

2017 ◽  
Author(s):  
Parul U Gandhi ◽  
James L Januzzi Jr
Keyword(s):  
Myocardial Infarction ◽  
Natriuretic Peptide ◽  
Amino Terminal ◽  
Coronary Syndrome ◽  
Patients With Heart Failure ◽  
Troponin Release ◽  
Universal Definition ◽  
Definition Of ◽  
Release Timing ◽  
Cardiovascular Biomarkers

The value of circulating biomarkers to care for patients with cardiovascular disease has grown significantly over the last few decades. The majority of clinical data focus on the use of natriuretic peptides (NPs) for the diagnosis, prognosis, and management of patients with heart failure (HF) and troponin measurements in patients with suspected or proven acute coronary syndrome (ACS). Part of the reason for the slow adoption of biomarkers beyond these two classes has been limitation in the optimal modes of application of new assays. Future studies are needed to clarify the use of biomarkers, with the ultimate goal of simplifying the diagnosis, prognosis, and patient care of complex cardiovascular conditions. This chapter reviews the use of established biomarkers for HF, ACS, and atrial fibrillation (AF). Tables include a summary of emerging and established cardiovascular biomarkers, characteristics of B-type natriuretic peptide and amino-terminal pro-B-type natriuretic peptide, cutoff points for NP measurement, differential diagnosis of elevated NP concentrations, biomarkers in HF with preserved ejection fraction, summary of NP management trials, third universal definition of myocardial infarction, and guidelines for recommendations of biomarkers in HF. Figures depict the various causes of NP release, the complex mechanism of troponin release in patients with HF, the ischemic and nonischemic etiologies of troponin release, timing of biomarker release during myocardial infarction, and the biomarkers involved in the pathogenesis of AF. Algorithms demonstrate evaluating outpatients with dyspnea in the clinic using NPs in their workup and the use of troponin to assist with determining an appropriate management strategy for a patient with ACS. This review contains 7 highly rendered figures, 8 tables, and 202 references.

Coronary sinus pressure and arterial flow during intermittent coronary sinus occlusion

1989 ◽  
Vol 256 (3) ◽  
pp. H906-H915
Author(s):  
F. Neumann ◽  
W. Mohl ◽  
W. Schreiner
Keyword(s):  
Coronary Sinus ◽  
Flow Curve ◽  
Methodological Approach ◽  
Venous Pressure ◽  
Artery Occlusion ◽  
Mean Value ◽  
Arterial Flow ◽  
The Mean ◽  
Release Ratio ◽  
Release Timing

The relationship between coronary artery flow and coronary venous pressure during intermittent coronary sinus occlusion was studied in dogs at normal perfusion, left anterior descending artery occlusion, and reperfusion. Coronary sinus occlusion and release phases were varied systematically. The periodicity of the data and the assumption of a linear relationship between pressure and flow suggested Fourier analysis as a methodological approach. To show the systematic slow oscillations of coronary venous pressure and arterial flow induced by intermittent occlusion of the coronary sinus, the data were smoothed by superimposing consecutive cycles of identical occlusion-release timing and filtering the higher frequencies. A small number of Fourier components, corresponding to the time scale of the respective occlusion-release cycle, was sufficient to study the long wavelength behavior. The effect of arbitrarily varying the occlusion-to-release ratio at a given total cycle length was investigated in hypothetical pressure and flow curves based on interpolation of experimental Fourier coefficients. By means of a transfer function relating pressure and flow in the frequency domain, it was possible to predict the arterial flow curve using coronary venous pressure measurements only. Because at zero frequency the pressure-flow relationship cannot be assumed to be linear, the mean value of flow could not be obtained in this way. However, the deviation of flow from the mean, i.e., the shape of the flow curve, was reproduced satisfactorily.

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