FRQ-CK1 Interaction Underlies Temperature Compensation of the Neurospora Circadian Clock

Temperature compensation allows clocks to adapt to all seasons by having a relatively constant period length at different physiological temperatures, but the mechanism of temperature compensation is unclear. Stability of clock proteins was previously proposed to be a major factor that regulated temperature compensation.

Using Repetitive Control to Enhance Force Control During Human-Robot Interaction in Quasi-Periodic Tasks

We investigated the use of repetitive control (RC) to enhance force control during human-robot interaction in quasi-periodic tasks. We first developed a two-mass spring damper model and formulated three different RCs under force control: a 1st order RC (RC-1), a 3rd order RC designed for random period error, and a 3rd order RC designed for constant period error. Then, we quantified the performance of these three RCs through simulations and experiments conducted on a bench top linear platform, subject to nominal cyclical inputs (input signal and fundamental frequency: 0.5 Hz), and subject to inputs with random and constant period errors. Moreover, we compared the performance achieved with the RCs with those achievable with a passive proportional controller (PPC), subject to known theoretical limits for passivity and coupled stability. In both simulated and real-world experiments, the root mean square force error under nominal conditions was reduced most effectively by the RC-1 to 0.7% and 12.9%, respectively, of the error achieved with the PPC. Subject to inputs with constant period errors, RCs performed better than PPC for period error values below 0.05 Hz, with the RC-1 performing significantly better than both 3rd order RCs. Subject to inputs with random period errors, all RCs performed better than PPC up to 0.11 Hz of frequency error. Our results indicate that RC can successfully integrated in force control schemes to improve performance beyond the one achievable with a PPC, in the range of period variability expected in applications such as walking assistance and rehabilitation.

INCREASED LIFE EXPECTANCY BASED ON PHYSICAL FORMULAS

Life expectancy is due to the frequency of processes occurring in the body. The lower the frequency, the longer the lifespan. The frequency is influenced by the fraction of vacuum particles in a free, unbound state. Elementary particles are connected, grouped particles of vacuum. But in a free state, a large proportion of them affect the frequency of oscillations, increasing it, therefore, reducing the lifetime. The connection between a living organism and an inanimate body has been drawn. Dislocations are analogous to vacuum particles. Their low density and low fraction of vacuum particles describe the theoretical ultimate strength and lifetime. The increase in density and the formation of crystalline elementary particles cause the average lifetime and average strength, orders of magnitude smaller than the theoretical one. A further increase in the dislocation density causes cracks and ruptures, and partly chaotic formation — tumors, partly crystalline. Chaos and order are described by a complex unified field that causes tumors. This unified field is described by the hydrodynamic, acoustic, complex Reynolds number with a small imaginary part. But the formation of a small imaginary Reynolds number is an inevitable process with increasing time, as is the formation of tumors. But how to deal with them. It is necessary for the tumors to pass from a partially chaotic state to a crystalline one, forming elementary particles. This requires a periodic unified field with a wavelength equal to a constant period, which is formed by vacuum particles in elementary, crystalline particles. In addition, an imaginary magnetic field is required, which has a sign opposite to the Reynolds number. Just irradiating the tumor will not help, you need a certain wavelength and a certain sign of the imaginary magnetic

Phase curve and variability analysis of WASP-12b using TESS photometry

We analyse Sector 20 TESS photometry of the ultra-hot Jupiter WASP-12b, and extract its phase curve to study the planet’s atmospheric properties. We successfully recover the phase curve with an amplitude of 549 ± 62 ppm, and a secondary eclipse depth of 609$^{+74}_{-73}$ ppm. The peak of the phase curve is shifted by 0.049 ± 0.015 in phase, implying that the brightest spot in the atmosphere is shifted from the substellar point towards the planet’s evening terminator. Assuming zero albedo, the eclipse depth infers a day-side brightness temperature of 3128$^{+64}_{-68}$ K. No significant detection of flux from the night-side is found at 60 ± 97 ppm, implying a night-side brightness temperature of <2529 K (1-σ). We do not detect any significant variability in the light from the planet over the ∼27 days of the TESS observations. Finally, we note that an ephemeris model taking orbital decay into account provides a significantly better fit than a constant-period model.

Evaluación preliminar de la Variabilidad de la Frecuencia Cardiaca de Pacientes con Fibrilación Auricular Paroxística y Apnea Obstructiva Barra lateral del artículo

This paper describes the processing of electrocardiographic (ECG) signals from 16 patients diagnosed with paroxysmal atrial fibrillation and sleep apnea-hypopnea syndrome (SAHS) classified as either moderate or severe by respiratory polygraphy. Processing goes from acquisition up to the analysis of their heart rate variability (HRV), where original computer scripts written in MATLAB R2020b are used within scripts adapted from other research groups. Computer processing included linear resampling, noise suppression, R-wave detection, misidentified peaks correction, tachogram resampling at a constant period and trend removal. Regular sampling is mandatory for Fourier analysis through Welch’s periodogram. Once the spectral power was estimated, the HRV was evaluated before, during and after an apnea episode. The behavior of the HRV was compared to the group of patients with moderate SAHS against those with severe SAHS. When comparing the groups at post-apnea stage, significant differences were found in the normalized low-frequency band (LF: 0.04–0.15Hz, p=0.0183), and also in the normalized high frequency band (HF: 0.15–0.4 Hz, p=0.0182), which suggests that in patients with severe SAHS the sympathetic activity is higher (power in LF band), which in turn presupposes that the autonomic nervous system is in frequent alertness, which has been associated with high cardiovascular risk.

Orbital period modulation in hot Jupiter systems

ABSTRACT We introduce a model for the orbital period modulation in systems with close-by giant planets based on a spin–orbit coupling that transfers angular momentum from the orbit to the rotation of the planet and vice versa. The coupling is produced by a permanent non-axisymmetric gravitational quadrupole moment assumed to be present in the solid core of the planet. We investigate two regimes of internal planetary rotation, that is, when the planet rotates rigidly and when the rotation of its deep interior is time-dependent as a consequence of a vacillating or intermittent convection in its outer shell. The model is applied to a sample of very hot Jupiters predicting maximum transit-time deviations from a constant-period ephemeris of approximately 50 s in the case of rigid rotation. The transit time variations of WASP-12, currently the only system showing evidence of a non-constant period, cannot be explained by assuming rigid rotation, but can be modelled in the time-dependent internal rotation regime, thus providing an alternative to their interpretation in terms of a tidal decay of the planet orbit.

Automated Code Inspection of Twitter Data using Software Repository Mining

The project proposes an application that reviews and analysis tweets on twitter application by doing software repository mining on the information gathered. The main purpose of this project is to investigate a few computational strategies to estimate the effect of web based life. Propelled by the techniques recently created to break down software systems and other unique frameworks, these strategies measure different static and dynamic parts of interpersonal organizations, the possibility and advantages of these estimation techniques with regards to Twitter is shown. By investigating the tweets the connection between the imperativeness of the news and the volume of the related tweets can be seen, which gets refreshed after every constant period of time. Using this strategy the tweets are ranked according to the highest priority.

CikA Modulates the Effect of KaiA on the Period of the Circadian Oscillation in KaiC Phosphorylation

Cyanobacteria contain a circadian oscillator that can be reconstituted in vitro. In the reconstituted circadian oscillator, the phosphorylation state of KaiC oscillates with a circadian period, spending about 12 h in the phosphorylation phase and another 12 h in the dephosphorylation phase. Although some entrainment studies have been performed using the reconstituted oscillator, they were insufficient to fully explain entrainment mechanisms of the cyanobacterial circadian clock due to the lack of input pathway components in the in vitro oscillator reaction mixture. Here, we investigate how an input pathway component, CikA, affects the phosphorylation state of KaiC in vitro. In general, CikA affects the amplitude and period of the circadian oscillation of KaiC phosphorylation by competing with KaiA for the same binding site on KaiB. In the presence of CikA, KaiC switches from its dephosphorylation phase to its phosphorylation phase prematurely, due to an early release of KaiA from KaiB as a result of competitive binding between CikA and KaiA. This causes hyperphosphorylation of KaiC and lowers the amplitude of the circadian oscillation. The period of the KaiC phosphorylation oscillation is shortened by adding increased amounts of CikA. A constant period can be maintained as CikA is increased by proportionally decreasing the amount of KaiA. Our findings give insight into how to reconstitute the cyanobacterial circadian clock in vitro by the addition of an input pathway component, and explain how this affects circadian oscillations by directly interacting with the oscillator components.

Variability of bacterial behavior in the mammalian gut captured using a growth-linked single-cell synthetic gene oscillator

The dynamics of the bacterial population that comprises the gut microbiota plays key roles in overall mammalian health. However, a detailed understanding of bacterial growth within the gut is limited by the inherent complexity and inaccessibility of the gut environment. Here, we deploy an improved synthetic genetic oscillator to investigate dynamics of bacterial colonization and growth in the mammalian gut under both healthy and disease conditions. The synthetic oscillator, when introduced into both Escherichia coli and Salmonella Typhimurium maintains regular oscillations with a constant period in generations across growth conditions. We determine the phase of oscillation from individual bacteria using image analysis of resultant colonies and thereby infer the number of cell divisions elapsed. In doing so, we demonstrate robust functionality and controllability of the oscillator circuit’s activity during bacterial growth in vitro, in a simulated murine gut microfluidic environment, and in vivo within the mouse gut. We determine different dynamics of bacterial colonization and growth in the gut under normal and inflammatory conditions. Our results show that a precise genetic oscillator can function in a complex environment and reveal single cell behavior under diverse conditions where disease may create otherwise impossible-to-quantify variability in growth across the population.