Fibroblast growth factor-21 improves insulin action in non-lactating ewes

During metabolically demanding physiological states, ruminants and other mammals coordinate nutrient use among tissues by varying the set point of insulin action. This set point is regulated in part by metabolic hormones with some antagonizing (e.g., growth hormone and TNFa) and others potentiating (e.g., adiponectin) insulin action. Fibroblast growth factor-21 (FGF21) was recently identified as a sensitizing hormone in rodent and primate models of defective insulin action. FGF21 administration, however, failed to improve insulin action in dairy cows during the naturally occurring insulin resistance of lactation, raising the possibility that ruminants as a class of animals or lactation as a physiological state are unresponsive to FGF21. To start addressing this question, we asked whether FGF21 could improve insulin action in non-lactating ewes. Gene expression studies showed that the ovine FGF21 system resembles that of other species, with liver as the major site of FGF21 expression and adipose tissue as a target tissue based on high expression of the FGF21 receptor complex and activation of p44/42 ERK1/2 following exogenous FGF21 administration. FGF21 treatment for 13 days reduced plasma glucose and insulin over the entire treatment period and improved glucose disposal during a glucose tolerance test. FGF21 increased plasma adiponectin by day 3 of treatment but had no effect on the plasma concentrations of total, C16:0-, or C18:0-ceramide. Overall, these data confirm that the insulin-sensitizing effects of FGF21 are conserved in ruminants and raise the possibility that lactation is an FGF21 resistant state.

Extended state observer based fractional order controller design for integer high order systems

In this paper, based on the extended state observer (ESO) and on a fractional order controller (FOC), composed of an integer order PID cascaded with a fractional order filter (FOF), a new control scheme for an n th order integer plant is proposed. The ESO is used to estimate and cancel the unknown internal dynamics and the external disturbance. Afterwards, an FOC is designed to resolve the set-point tracking problem. An analytical and systematic method is proposed to design the FOC. This method is based on the Internal Model Control (IMC) and the Bode’s Ideal Transfer Function (BITF). Therefore, the proposed control structure improves the robustness and performance of the traditional linear active disturbance rejection control (LADRC), especially for the open-loop gain variation. In addition, since the system be controlled is an n th order, a general form of the BITF is also proposed. Numerical simulations on a nonlinear model and experimental results on a cart-pendulum system design illustrate the effectiveness of the suggested ESO-PID-FOF scheme for the disturbance rejection, the set-point tracking and robustness. A comparison with the results obtained using the standard LADRC is also presented.

Roles of Oxytocin in Stress Responses, Allostasis and Resilience

Oxytocin has been revealed to work for anxiety suppression and anti-stress as well as for psychosocial behavior and reproductive functions. Oxytocin neurons are activated by various stressful stimuli. The oxytocin receptor is widely distributed within the brain, and oxytocin that is released or diffused affects behavioral and neuroendocrine stress responses. On the other hand, there has been an increasing number of reports on the role of oxytocin in allostasis and resilience. It has been shown that oxytocin maintains homeostasis, shifts the set point for adaptation to a changing environment (allostasis) and contributes to recovery from the shifted set point by inducing active coping responses to stressful stimuli (resilience). Recent studies have suggested that oxytocin is also involved in stress-related disorders, and it has been shown in clinical trials that oxytocin provides therapeutic benefits for patients diagnosed with stress-related disorders. This review includes the latest information on the role of oxytocin in stress responses and adaptation.

Improving Homeostatic Set-Point through Proper Training Adaptations for Better Sporting Outcome

The concept of homeostasis is based on Darwin’s theory of survival of the fittest. In order to survive one has to maintain a stable internal and external environment. For attaining positive change of an individual’s physical, physiological, psychological, and mechanical performance stress is required in a systematic and scientific planned way. Regular upsetting the homeostatic set point, a new set-point is able to create within the body, which can be termed as adaptation. In the case of sports performance, the training load must be adopted by an athlete through the process of super-compensation in order to exhibit better performance in the competitive sports arena. Adaptation is facilitated the positive reinforcement through a negative feedback loop in physical, physiological, and psychological areas of any individual and able to develop the concept of feed-forward mechanism. If adaptation stimuli are applied properly, training can be expected to have accumulative effect. The sporting world depends upon the positive adaptation of training load through improving the sporting performance by elevating the homeostatic set point. Long term training has also positive impact on health sports performance by modifying the qualitative and quantitative physiological component. A physiological adaptation refers to the metabolic or physiologic adjustment within the cell, or tissues, of an organism in response to an environmental stimulus resulting in the improved ability of that organism to cope with its changing environment adaptation. The purpose of the present study is to critically discuss the various aspects of homeostatic regulations and the way to create a new set point of an athlete for better performance through the adaptation process.

Simulation and Implementation PID Controlling Buck Converter DC

Regulating the output voltage based on the desired set point is useful for many applications. However, getting the optimal value using fast computation with minimal error is still challenging. This paper aims to design, simulate, and implement a second-order Buck-Boost DC-DC converter circuit so that the voltage result according to the desired set point can be achieved. Initially, testing is conducted using Matlab Simulink. Then, Proteus is used to test the computation of the program on embedded systems in which the result is implemented in C. In low voltage power electronics applications, this approach has never been used to determine the output form. To determine the value of Kp, Ki, dan Kd, PID, Ziger Nichos (Guo, 2002). method is used. Meanwhile, tuning is done through Matlab. For simulation on Proteus, the output is tested by setting the setpoint values of 3.0, 2.5, and 1.7 volts. This aims to see the pattern of changes in the simulation. The simulation results with Proteus show that they have similar peak values but with different overshoot values. This is because the simulation must pass the reference voltage before it drops to the desired setpoint value. Proteus simulation can also help to prove embedded system programs are running correctly. On the other hand, the value of 1.7 volts is used as a setpoint in device implementation. This is due to the determination that the setpoint voltage in the implementation does not exceed the value of the source/power supply. The results show that for the rise time value of 378,770 ms, Overshoot and settling time are 11.798% and 0, respectively. This means the result produces an optimal value which is a return to the initial target. The optimal factor is assessed from the ability to minimize existing errors as well as having the shortest possible computational process.

Dimensions of Psychological Well-being and Subjective Happiness in the New Normal: An Exploration

The pandemic has brought in unprecedented changes in societies across the globe. It has altered the equilibrium and forced individuals to move out of their comfort zone, leading to disturbance in psychological well-being in the new normal (Kuster, 2021). This empirical study examines the effect of psychological well-being (PWB) on subjective happiness (SH) of students of higher educational institutions (HEIs) during the global pandemic. Total of 290 students of HEIs were administered with the PWB questionnaire and SH questionnaire. The relationship between the variables was examined using multiple regression. The results indicated that the SH levels of the sample were above average (M = 19.76). SH was found to be more in women. No gender difference was found in PWB levels. The findings also revealed that improving PWB will positively influence the SH (r = 0.581) of the students. PWB can explain 32% variation of SH. Self-acceptance (p = .01), autonomy (p = .01), positive relationships with others (p = .03), and personal growth (p = .002) increases the feeling of SH. The findings validate the set point theory that while recent life events influence SH, individuals tend to return to natural set point over a period in time. The findings add to the repertoire of research on PWB and SH in the context of Set point theory. Study findings can help in strategizing the student counselling process as well as curriculum design of HEIs to ensure greater SH of its stakeholders.

Case Study of a Novel Autonomous Real-Time Monitoring, Control and Analysis System, to Maximize Production Uptime on Sustained Annulus Pressure Wells, While Improving HSE and Compliance with Double Barrier Well Integrity Policies

This paper describes an innovative solution for the safe and effective management of wells with unplanned sustained annulus pressure (SAP). The solution restores double barrier integrity in the well and provides reliable real time annulus pressure and temperature data. It also has the functionality to autonomously bleed-off the annulus pressure at a pre-determined set point. As a result, the nature and severity of the SAP can be better understood, and in many cases wells that would otherwise have been closed in awaiting workover can remain in production.