Price Rate of Change

2015 ◽  
pp. 51-60
Keyword(s):  
Rate Of Change

Decreasing water pressure cues ‘bailout’ in seaweed-associated crustaceans

2020 ◽  
Vol 653 ◽  
pp. 121-129
Author(s):  
RB Taylor ◽  
S Patke
Keyword(s):  
Water Pressure ◽  
Rapid Change ◽  
Brown Seaweed ◽  
Model System ◽  
Rate Of Change ◽  
Suitable Habitat ◽  
Changing Light ◽  
Surface Increase ◽  
Reduced Water ◽  
Transparent Chamber

Small mobile crustaceans are abundant on seaweeds. Many of these crustaceans rapidly abandon their host if it is detached from the seafloor and floats towards the surface, but the trigger for this ‘bailout’ behaviour is unknown. We tested 2 potential cues, i.e. rapid change in light and rapid change in water pressure, using >1 mm epifauna on the brown seaweed Carpophyllum plumosum as a model system. Bailout occurred in response to reduced water pressure, but not to changing light, as (1) bailout occurred at similar rates in light and dark, (2) bailout occurred on the seafloor when water pressure was reduced within a transparent chamber by the equivalent of ~0.5 m depth or more, and (3) little bailout occurred when water pressure was held constant within the chamber while seaweeds were raised to the surface. Increase in pressure (simulating sinking) did not induce bailout. The rate of bailout increased with increasing magnitude of pressure reduction but was not influenced greatly by the rate of change of pressure within the range tested (up to an equivalent of 0.4 m depth s-1). The use of pressure rather than light as a cue for bailout is consistent with the need for seaweed-associated crustaceans to rapidly abandon a detached host and relocate to suitable habitat during both day and night.

Dry Matter Production and Rate of Change of Harvest Index at High Temperature in Peanut

Crop Science ◽  
2002 ◽  
Vol 42 (1) ◽  
pp. 146 ◽  
Author(s):  
P. Q. Craufurd ◽  
P. V. Vara Prasad ◽  
R. J. Summerfield
Keyword(s):  
High Temperature ◽  
Harvest Index ◽  
Dry Matter ◽  
Rate Of Change ◽  
Dry Matter Production ◽  
Matter Production

Mixed Layer Models and Their Application to Water Quality Problems

1994 ◽  
Vol 29 (2-3) ◽  
pp. 221-232
Author(s):  
M.J. McCormick
Keyword(s):  
Water Quality ◽  
Mixed Layer ◽  
Thermal Structure ◽  
Mass Conservation ◽  
Eddy Diffusion ◽  
Rate Of Change ◽  
Surface Mixed Layer ◽  
Storm Events ◽  
Quality Model ◽  
Mixing Processes

Abstract Four one-dimensional models which have been used to characterize surface mixed layer (ML) processes and the thermal structure are described. Although most any model can be calibrated to mimic surface water temperatures, it does not imply that the corresponding mixing processes are well described. Eddy diffusion or "K" models can exhibit this problem. If a ML model is to be useful for water quality applications, then it must be able to resolve storm events and, therefore, be able to simulate the ML depth, h, and its time rate of change, dh/dt. A general water quality model is derived from mass conservation principles to demonstrate how ML models can be used in a physically meaningful way to address water quality issues.

Temperature control in a chemical reactor through variable area of the heat transfer surface. Simulation analysis

1982 ◽  
Vol 47 (2) ◽  
pp. 430-445
Author(s):  
Josef Horák ◽  
Zina Valášková
Keyword(s):  
Heat Exchange ◽  
Simulation Analysis ◽  
Batch Reactor ◽  
Chemical Reactor ◽  
Rate Of Change ◽  
Action Variable ◽  
Heat Exchange Surface ◽  
Relay With Hysteresis ◽  
Exchange Surface

An algorithm has been developed and on a mathematical model analyzed to stabilize the reaction temperature of a batch reactor. The reaction has been a zero-order one and the reactor has been operated in a instable operating point. The action variable is the heat exchange surface whose area is increased if the temperature is above, or decreased if the temperature is below the set point. The following two-point regulators have been studied: An ideal relay, a relay with hysteresis and an asymmetric PD relay. The effect has been discussed of the parameters of the regulators on the quality of regulation. Stability analysis has been made of the stationary switching cycles and the domains of applicability have been determined for individual regulators with respect to the rate of change of the area of heat exchange surface.

A walking bout reveals altered foot thermodynamics associated with unilateral transtibial amputation among individuals with type 2 diabetes

2020 ◽  
pp. 030936462096864
Author(s):  
Kyle R Leister ◽  
Shane R Wurdeman
Keyword(s):  
Type 2 Diabetes ◽  
Temperature Change ◽  
Foot Ulcer ◽  
Diabetic Foot Ulcer ◽  
Rate Of Change ◽  
Peak Temperature ◽  
Cross Sectional ◽  
Contralateral Limb ◽  
Transtibial Amputation

Background: Increased foot temperature among individuals with type 2 diabetes can be predictive of diabetic foot ulcer development. A combination of physiological and mechanical deficiencies may contribute to elevations in intact foot temperature during gait for individuals with type 2 diabetes and transtibial amputation. Objective: This study evaluated plantar foot temperature differences between individuals with type 2 diabetes with and without transtibial amputation. We hypothesized that individuals with transtibial amputation maintain increased foot temperature compared to those without amputation. Study Design: Cross-sectional, case control. Methods: A sample of 16 participants with type 2 diabetes and transtibial amputation, and 16 age- and sex-matched participants with type 2 diabetes without amputation were recruited. Foot temperatures were measured during resting, walking, and cooldown periods. Peak temperature, mean temperature, and rate of temperature change were analyzed for each period, and compared between cohorts. Results: Participants with amputation exhibited increased mean foot temperature while at rest and during walking. Participants without amputation exhibited increased rate of change of foot temperature during walking. No differences in peak temperature or rate of temperature change were observed during the baseline or cooldown periods. Conclusion: The current findings of altered foot temperature for individuals with transtibial amputation and type 2 diabetes suggest a possible reason for the high rates of contralateral limb ulceration and amputation among this population.

scholarly journals Longitudinal analysis of intervention effects on temptations and stages of change for dietary fat using parallel process latent growth modeling

2016 ◽  
Vol 24 (5) ◽  
pp. 572-585 ◽  
Author(s):  
Leslie Ann D Brick ◽  
Si Yang ◽  
Lisa L Harlow ◽  
Colleen A Redding ◽  
James O Prochaska
Keyword(s):  
Stages Of Change ◽  
Daily Intake ◽  
Rate Of Change ◽  
Dietary Guidelines ◽  
High Fat ◽  
Latent Growth ◽  
Intervention Effects ◽  
Randomized Controlled ◽  
Stage Of Readiness ◽  
Dietary Guidelines For Americans

The Dietary Guidelines for Americans recommend a 20–35 percent daily intake of fat. Resisting the temptation to eat high-fat foods, in conjunction with stage of readiness to avoid these foods, has been shown to influence healthy behavior change. Data ( N = 6516) from three randomized controlled trials were pooled to examine the relationships among direct intervention effects on temptations and stage of change for limiting high-fat foods. Findings demonstrate separate simultaneous growth processes in which baseline level of temptations, but not the rate of change in temptations, was significantly related to the change in readiness to avoid high-fat foods.

scholarly journals Perioperative Geriatric Assessment as A Predictor of Long-Term Hepatectomy Outcomes in Elderly Patients with Hepatocellular Carcinoma

Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 842
Author(s):  
Masaki Kaibori ◽  
Hideyuki Matsushima ◽  
Morihiko Ishizaki ◽  
Hisashi Kosaka ◽  
Kosuke Matsui ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Geriatric Assessment ◽  
Proportional Hazards ◽  
Prognostic Indicator ◽  
Cox Proportional Hazards ◽  
Rate Of Change ◽  
Score Change ◽  
Comorbidity Burden ◽  
Reduction Group

This retrospective study recorded pertinent baseline geriatric assessment variables to identify risk factors for recurrence-free survival (RFS) and overall survival (OS) after hepatectomy in 100 consecutive patients aged ≥70 years with hepatocellular carcinoma. Patients had geriatric assessments of cognition, nutritional and functional statuses, and comorbidity burden, both preoperatively and at six months postoperatively. The rate of change in each score between preoperative and postoperative assessments was calculated by subtracting the preoperative score from the score at six months postoperatively, then dividing by the score at six months postoperatively. Patients with score change ≥0 comprised the maintenance group, while patients with score change <0 comprised the reduction group. The change in Geriatric 8 (G8) score at six months postoperatively was the most significant predictive factor for RFS and OS among the tested geriatric assessments. Five-year RFS rates were 43.4% vs. 6.7% (maintenance vs. reduction group; HR, 0.19; 95%CI, 0.11–0.31; p < 0.001). Five-year OS rates were 73.8% vs. 17.8% (HR, 0.12; 95%CI, 0.06–0.25; p < 0.001). Multivariate Cox proportional hazards analysis showed that perioperative maintenance of G8 score was an independent prognostic indicator for both RFS and OS. Perioperative changes in G8 scores can help forecast postoperative long-term outcomes in these patients.

scholarly journals Plasma NfL levels and longitudinal change rates in C9orf72 and GRN-associated diseases: from tailored references to clinical applications

2021 ◽  
pp. jnnp-2021-326914
Author(s):  
Dario Saracino ◽  
Karim Dorgham ◽  
Agnès Camuzat ◽  
Daisy Rinaldi ◽  
Armelle Rametti-Lacroux ◽  
...  
Keyword(s):  
Single Molecule ◽  
Light Chain ◽  
Rate Of Change ◽  
Longitudinal Change ◽  
Youden Index ◽  
Clinical Genetic ◽  
Neurofilament Light Chain ◽  
Neurofilament Light ◽  
Link Type ◽  
Therapeutic Trials

ObjectiveNeurofilament light chain (NfL) is a promising biomarker in genetic frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). We evaluated plasma neurofilament light chain (pNfL) levels in controls, and their longitudinal trajectories in C9orf72 and GRN cohorts from presymptomatic to clinical stages.MethodsWe analysed pNfL using Single Molecule Array (SiMoA) in 668 samples (352 baseline and 316 follow-up) of C9orf72 and GRN patients, presymptomatic carriers (PS) and controls aged between 21 and 83. They were longitudinally evaluated over a period of >2 years, during which four PS became prodromal/symptomatic. Associations between pNfL and clinical–genetic variables, and longitudinal NfL changes, were investigated using generalised and linear mixed-effects models. Optimal cut-offs were determined using the Youden Index.ResultspNfL levels increased with age in controls, from ~5 to~18 pg/mL (p<0.0001), progressing over time (mean annualised rate of change (ARC): +3.9%/year, p<0.0001). Patients displayed higher levels and greater longitudinal progression (ARC: +26.7%, p<0.0001), with gene-specific trajectories. GRN patients had higher levels than C9orf72 (86.21 vs 39.49 pg/mL, p=0.014), and greater progression rates (ARC:+29.3% vs +24.7%; p=0.016). In C9orf72 patients, levels were associated with the phenotype (ALS: 71.76 pg/mL, FTD: 37.16, psychiatric: 15.3; p=0.003) and remarkably lower in slowly progressive patients (24.11, ARC: +2.5%; p=0.05). Mean ARC was +3.2% in PS and +7.3% in prodromal carriers. We proposed gene-specific cut-offs differentiating patients from controls by decades.ConclusionsThis study highlights the importance of gene-specific and age-specific references for clinical and therapeutic trials in genetic FTD/ALS. It supports the usefulness of repeating pNfL measurements and considering ARC as a prognostic marker of disease progression.Trial registration numbersNCT02590276 and NCT04014673.

Sign in / Sign up

Export Citation Format

Share Document