Heart Rate Response to Sound and Light

Heart rate response to varying sound and light intensitie

A model of heart rate kinetics in response to exercise

We present a mathematical model, in the form of two coupled ordinary differential equations, for the heart rate kinetics in response to exercise. Our heart rate model is an adaptation of the model of oxygen uptake kinetics of Stirling: a physiological justification for this adaptation, as well as the physiological basis of our heart rate model is provided. We also present the optimal fit of the heart rate model to a set of raw un averaged data for multiple constant intensity exercises for an individual at a particular level of fitness

The Contribution of Growth and Interest Rate Differentials to the Persistence of Real Exchange Rates.

This paper employs a new methodology for measuring the contribution of growth and interest rate differentials to the half-life of deviations from Purchasing Power Parity (PPP). Our method is based on directly comparing the impulse response function of a VAR model, where the real exchange rate is Granger caused by these variables with the impulse response function of a univatiate ARMA model for the real exchange rate. We show that the impulse response function of the VAR model is not, in general, the same with the impulse response function obtained from the equivalent ARMA representation, if the real exchange rate is Granger caused by other variables in the system. The difference between the two functions captures the effects of the Granger-causing variables on the half-life of deviations from PPP. Our empirical results for a set of four currencies suggest that real and nominal long term interest rate differentials and real GDP growth differentials account for 22% to 50% of the half-life of deviations from PPP.real exchange rate; persistence measures; VAR; impulse response function; PPP

Regimes of heating and dynamical response in driven many-body localized systems

We explore the response of many-body localized (MBL) systems to periodic driving of arbitrary amplitude, focusing on the rate at which they exchange energy with the drive. To this end, we introduce an infinite-temperature generalization of the effective "heating rate" in terms of the spread of a random walk in energy space. We compute this heating rate numerically and estimate it analytically in various regimes. When the drive amplitude is much smaller than the frequency, this effective heating rate is given by linear response theory with a coefficient that is proportional to the optical conductivity; in the opposite limit, the response is nonlinear and the heating rate is a nontrivial power-law of time. We discuss the mechanisms underlying this crossover in the MBL phase, and comment on its implications for the subdiffusive thermal phase near the MBL transition.Comment: 17 pages, 9 figure

A Potential Function Derivation of a Constitutive Equation for Inelastic Material Response

Physical and thermodynamic concepts are used to develop a potential function for application to high temperature polycrystalline material response. Inherent in the formulation is a differential relationship between the potential function and constitutive equation in terms of the state variables. Integration of the differential relationship produces a state variable evolution equation that requires specification of the initial value of the state variable and its time derivative. It is shown that the initial loading rate, which is directly related to the initial hardening rate, can significantly influence subsequent material response. This effect is consistent with observed material behavior on the macroscopic and microscopic levels, and may explain the wide scatter in response often found in creep testing

Interest Rate Rules and the Response to the Output Gap

Modern monetary policy analysis is built around the concept of an interest rate rule that responds to both inflation and output. This paper evaluates the quantitative implications of having a policy rule target different definitions of the output gap in a New Keynesian model with endogenous capital. One crucial result is that different model specifications result in alternative values for potential output, raising the issue of which output gap to target. The results of this paper suggest that targeting the true output gap can be well approximated by a rule that only reacts to inflation.Monetary Policy Rules, Output Gap

Response behaviour of oxygen sensing solid electrolytes

The response time (t r) after a step change in oxygen partial pressure was investigated for some solid electrolytes used in Nernst type oxygen sensors. The electrolyte as well as the (porous) electrode material affect the value oft r. Stabilized Bi2O3 materials exhibit slower response rates (largert r values) than stabilized ZrO2. Introduction of Bi2O3 in stabilized ZrO2 increases the response time. Gold electrodes show a higher response rate than platinum in the oxygen partial pressure and temperature region used.\u

The Negativity Bias Predicts Response Rate To Behavioral Activation For Depression

Background and Objectives: This treatment study investigated the extent to which asymmetric dimensions of affective responding, specifically the positivity offset and the negativity bias, at pretreatment altered the rate of response to Behavioral Activation treatment for depression. Method: Forty-one depressed participants were enrolled into 16 weekly sessions of BA. An additional 36 lifetime healthy participants were evaluated prospectively for 16 weeks to compare affective responding between healthy and remitted patients at post-treatment. All participants were assessed at Weeks 0, 8 and 16 using repeated measures, involving a structured clinical interview for DSM-IV Axis I disorders, questionnaires, and a computerized task designed to measure affective responses to unpleasant, neutral, and pleasant images. Results: The negativity bias at pre-treatment predicted the rate of response to BA, while the positivity offset did not. Limitations: Only one treatment condition was used in this study and untreated depressed participants were not enrolled, limiting our ability to compare the effect of BA. Conclusions: Baseline negativity bias may serve as a signal for patients to engage in and benefit from the goal-directed BA strategies, thereby accelerating rate of response

Treating cisplatin-resistant cancer: a systematic analysis of oxaliplatin or paclitaxel salvage chemotherapy

Objective: To examine the pre-clinical and clinical evidence for the use of oxaliplatin or paclitaxel salvage chemotherapy in patients with cisplatin-resistant cancer. Methods: Medline was searched for 1) Cell models of acquired resistance reporting cisplatin, oxaliplatin and paclitaxel sensitivities and 2) Clinical trials of single agent oxaliplatin or paclitaxel salvage therapy for cisplatin/carboplatin-resistant ovarian cancer. Results: Oxaliplatin - Oxaliplatin is widely regarded as being active in cisplatin-resistant cancer. In contrast, data in cell models suggests that there is cross-resistance between cisplatin and oxaliplatin in cellular models with resistance levels which reflect clinical resistance (<10 fold). Oxaliplatin as a single agent had a poor response rate in patients with cisplatin-resistant ovarian cancer (8%, n=91). Oxaliplatin performed better in combination with other agents for the treatment of platinum-resistant cancer suggesting that the benefit of oxaliplatin may lie in its more favourable toxicity and ability to be combined with other drugs rather than an underlying activity in cisplatin resistance. Oxaliplatin therefore should not be considered broadly active in cisplatin-resistant cancer. Paclitaxel – Cellular data suggests that paclitaxel is active in cisplatin-resistant cancer. 68.1% of cisplatin-resistant cells were sensitive to paclitaxel. Paclitaxel as a single agent had a response rate of 22% in patients with platinum-resistant ovarian cancer (n = 1918), a significant increase from the response of oxaliplatin (p<0.01). Paclitaxel-resistant cells were also sensitive to cisplatin, suggesting that alternating between agents may be beneficial. Studies of single agent paclitaxel in platinum-resistant ovarian cancer where patients had previously received paclitaxel had an improved response rate of 35.3% n=232 (p<0.01), suggesting that pre-treatment with paclitaxel improves the response of salvage paclitaxel therapy. Conclusions: Cellular models reflect the resistance observed in the clinic as the cross resistant agent oxaliplatin has a lower response rate compared to the non-cross resistant agent paclitaxel in cisplatin-resistant ovarian cancer. Alternating therapy with cisplatin and paclitaxel may therefore lead to an improved response rate in ovarian cancer