Working Cycle Research Articles

Estimation of Pro-Inflammatory Markers In Night Shift Healthcare Workers And Identify Risk Factors Associated With It

Shift labor, with hours outside of the regular diurnal work cycle, is used to facilitate round-the-clock emergency healthcare services. This impacts the circadian rhythm, which can potentially activate the pro-inflammatory responses of the immune system. This study aimed to find out the levels of pro-inflammatory markers in night shift healthcare workers and find risk factors associated with their increase. 303 participants (doctors, nurses, technicians, health care aids) were recruited with 169 participants nightshift and 134 dayshift workers. Pro-inflammatory markers Highly Sensitive C-Reactive Protein (hsCRP) and Total Leukocyte Count (TLC)] were estimated. Factors were compared by t test, Wilcoxon Rank Sum test and Chi square test. Risk factors for hsCRP elevation were identified by logistic regression analysis. Pro-inflammatory markers like hsCRP and TLC were significantly increased in night shift health workers in comparison to the day shift workers (hsCRP 0.30± 0.33 mg/dl vs 0.10± 0.09 mg/dl, TLC 8181.06± 1181.53 /cu mm vs 7473.80± 1018.81 /cu mm) respectively. Multivariate logistic regression analysis showed night shift work (OR 48.20 95% CI (4.99-465.61), age (OR 1.13 95% CI (1.01-1.26)) and BMI (OR 1.18 95% CI (1.06-1.32)) as independent predictors of elevated hsCRP after adjusting for other risk factors. Hence, night-shift work is an independent risk factor for a rise in pro-inflammatory markers. These findings might aid health care workers and policymakers strategize methods to tackle the challenges through providing support programs, counselling sessions to avoid ailments and deliver health services in a better way.

Study of operating modes of electromagnetic hammer with adjustable impact energy and blow frequency

The current work was designed to study the operating modes of electromagnetic impact mechanism (electromagnetic hammer) comprising idle and working stroke windings that are enclosed in magnetic conductor, and reciprocating ferromagnetic striker. Investigation was conducted by modelling in MATLAB environment and performing verification tests with different hammers. Simulation model of the hammer was derived using experimentally obtained static characteristic curves of flux linkage and thrust force for each of the windings. Results revealed that at maximum working stroke winding voltage-varying idle stroke winding voltage, the impact energy did not change, but the impact frequency varied between 0-187 bpm. At maximum idle stroke winding voltage and working stroke winding voltage ranging between 0 to maximum value, the impact energy varied between 84-360 J, the impact frequency varied between 96-187 bpm. Maximum losses over the working cycle were associated with electric losses in the hammer windings and can be reduced by reducing winding currents through increasing the striker speed. The mathematical model of the current study allowed quantifying energy parameters of the electromagnetic hammer. The impact machine cycle includes three operating modes, each determines the main energy parameters: efficiency, impact energy, and cycle time.

Justification the surface mining system parameters of amber pits with semi-mobile beneficiation plants

Research is aimed at establishing the dependence of the semi-mobile beneficiation plant productivity on the face width of the excavator at the developing amber deposits. Analytical research methods were used at the development of the methodology to determine the working time of excavator, taking into account the time for moving the enrichment plant. Appropriate calculation methods are relevant for determining the required amount of technical equipment that ensures the mining operation. The efficient parameters of the face width during the excavation of mining mass have been established, depending on the parameters of the excavator boom, taking into account its replacement. It was determined that the duration of the working cycle of working out the block with the corresponding face width of the pit is based on the time of loading and moving the semi-mobile beneficiation plant, as well as the time for reexcavation. The effective width of the working pit face was calculated with the appropriate choice of the excavator boom. The established parameters of the face width of the pit on the mining bench with the loading of mining mass to the semi-mobile concentrator were implemented in the pit at the development of the Galbin-24 amber deposit.

Assessment of the Impact of the COVID-19 Pandemic on the Economy of Russian Regions

The COVID-19 pandemic has had a serious impact on the sustainability of the social, economic and environmental development of countries and regions. Differences in the structure of the economy of the subjects of Russia and the rate of spread of infection give rise to an assumption about the spatial unevenness of the economic consequences of the COVID-19 pandemic. The purpose of this work is to determine the degree of impact of COVID-19 on various types of regional economies, taking into account industry specifics. The article presents the theoretical base of the study based on foreign and domestic sources, considers the spread of coronavirus infection in the regions of the Russian Federation using the indicator “total number of cases of COVID-19 (per 1000 people)”, the dynamics of the unemployment rate at working age in the regions of Russia in 2018–2021, the dynamics of economic growth in the regions of the Russian Federation and the dynamics of the growth rate of GRP by sectors of the economy during the COVID-19 pandemic, specialization of the regions of the Russian Federation. Based on the results of the study, the regions of the Russian Federation were ranked according to the degree of influence of COVID-19 on their economic sphere: a) regions whose specialization is determined by natural and geographical factors (with the exception of tourism) experienced the least impact of the COVID-19 pandemic; b) regions whose economies are highly differentiated, large industrial and financial enterprises are located on their territory, the economic sphere of this group of regions has experienced a significant impact of the COVID-19 pandemic, but recovery has been rapid; c) regions in whose economy a number of pandemic risk factors have been concentrated; d) economic outsider regions in the Russian Federation. The conducted research complements the cycle of works in the field of the impact of epidemics on the economy of regions and countries. The results obtained can be used to develop and implement a risk management policy to mitigate the consequences of anti-epidemic measures in the regions of the Russian Federation.

High cadence cycling not high work rate, increases gait velocity post-exercise

ABSTRACT Gait velocity, or walking speed, has been referred to as the sixth vital sign, and research suggests that it is highly sensitive to change. Previous research has demonstrated the utility of cycling to improve gait parameters and in particular gait velocity in a variety of populations. However, it is unclear if the benefits from cycling to gait velocity stem from increased cadence, increased work rate, or the interaction between them. Therefore, the objective of the current research was to explicitly test the relationship between cycling work rate, cycling cadence, and gait velocity. 45 recreationally active young adults were randomly assigned to cycle at a normalised cadence and work rate, a higher cadence, or a higher work rate (CONTROL, FAST, HARD). All participants completed two ten-metre walk tests (10 MWT) pre- and post-cycling intervention. There was a significant interaction between group and time and post hoc comparisons showed that the FAST group walked significantly faster than the HARD group post-cycling. These results support the hypothesis that cycling at a cadence greater than the comfortable walking cadence, and not cycling at an increased work rate, increased gait velocity post-exercise for all members of our sample of healthy young adults.

Post-process updating of model parameters to approximate thermal errors of machine tools operating in different configurations

Machine tool (MT) thermal errors induced by external and internal heat sources (e.g. changing environment, friction and power losses in MT components) are an important element in machined workpiece inaccuracies. In the past few decades, indirect software compensation techniques have been used to address thermal errors on account of their economic and ecological aspects. Many slightly different approaches are described in the literature. If thermal error models are properly identified based on experiments with sufficiently varying input parameters, they usually work within similar calibration and verification conditions. As the sensory equipment of machines increases, models can be adapted to regions with higher thermo-mechanical system nonlinearity and inhomogeneity through the introduction of deformation feedback from direct measurements into model structures. However, adaptive functionalities require discrete interruptions of the MT's work cycle, which threaten the integrity of the machined surface and complicate the model structure and thus also implementation and industrial deployment possibilities. In this research, a novel approach of automatic post-process adaptation suitable for repetitive manufacturing, which takes advantage of transfer functions (TF), is proposed for thermal error reduction. The method respects basic heat transfer mechanisms in the MT structure by combining linear parametric models, requires a minimum of additional gauges, and feedback from direct measurements is obtained only during technological pauses in the production process. Post-process adaptation is solved retrospectively by updating model parameters using the heuristic method of genetic algorithms (GA). First, the approach was tuned on a case study of a heavy-duty milling machine with a horizontal headstock for a configuration with an exchangeable spindle head and a configuration with a change in the position of the headstock in the workspace, both of which were different from the initial model's calibration range. Subsequently, the developed approach was applied to repeated production on a medium-sized milling centre. Another goal of the paper is to emphasize the need for quality input information for modelling efforts and the industrial applicability of scientific results.

Experimental Investigation of a Pulsation Reactor via Optical Methods

Material treatment in pulsation reactors (PRs) offers the potential to synthesize powdery products with desirable properties, such as nano-sized particles and high specific surface areas, on an industrial scale. These exceptional material characteristics arise from specific process parameters within PRs, characterized by the periodically varying conditions and the resulting enhanced heat and mass transfer between the medium and the particulate material. Understanding flame behavior and the re-ignition mechanism is crucial to controlling the efficiency and stability of the pulse combustion process. In order to accomplish this objective, an investigation was conducted into flame behavior within the combustion chamber of a Helmholtz-type pulsation reactor. The study was focused on primarily analyzing the flame propagation process and examining flame velocity throughout the operational cycle of the reactor. Two optical methods—natural flame luminosity (NFL) and particle image velocimetry (PIV)—were applied in related experiments. An analysis of the NFL measurement data revealed a correlation between the intensity of light emitted by the pulsed flame and the air-fuel equivalence ratio (range from 0.89 to 2.08 in this study). It is observed that a lower air-fuel equivalence ratio leads to higher flame luminosity in the PR. In addition, in order to study the parameters related to system stability and energy transfer efficiency, this study also focuses on the local velocity field measurement method and an example of a fluid flow result in a combustion chamber by using a phase-locked PIV measurement system upgraded from a classic PIV system. The presented results herein contribute to the characterization of flame propagation within a pulsation reactor, as well as in pulsatile flows over one working cycle in a broader context, with flow velocity in the center of the combustion chamber ranging from 1.5 m/s to 5 m/s. Furthermore, this study offers insights into the applicable experimental methodologies for investigating the intricate interplay between flames and flows within combustion processes.

ОГНЕВЫЕ ИСПЫТАНИЯ МОБИЛЬНОЙ УНИВЕРСАЛЬНОЙ УСТАНОВКИ ПОЖАРОТУШЕНИЯ

To assess the effectiveness of a full-size mobile universal fire extinguishing system, fire tests of the developed layout of an experimental mobile universal fire extinguishing system were carried out, taking into account the requirements of national standards, which determined the choice of the operating pressure range and nozzle diameters. Numerical values of the duration of the supply, the length of the jet and the rate of discharge of fire extinguishing agent from the vessel of the layout of a mobile universal fire extinguishing system from the diameters of the nozzles with a change in pressure are obtained. The results showed that
 the duration of the supply and the length of the jet of fire extinguishing agent, regardless of the diameters of the nozzles, depend on the pressure, the flow rate and outflow rate of fire extinguishing agent depend on both the diameters of the nozzles and the pressure. The relationship between the parameters of the layout and its extinguishing capacity has been determined, which confirms the declared capabilities of its working cycle.

A Simulation Study of Noise Exposure in Sledge-Based Cable Yarding Operations

Ensuring the safety of forestry workers is a key challenge, particularly when working with partly mechanized harvesting systems. Cable yarding is typically used in steep terrain timber harvesting. For long-distance extraction, one of the few alternatives is to use sledge yarders, but these machines may expose workers to high doses of noise. The goal of this study was to model haulers’ exposure to noise in sledge-based cable yarding operations, based on a simulation approach that considered variable factors such as the yarding distance, lateral yarding distance, and average skyline height. Taken into consideration were 165 scenarios developed by examining the variation in yarding distance (500 to 1500 m, with a step of 100 m), lateral yarding distance (10 to 50 m, with a step of 10 m), and average skyline height above the ground (10, 15, and 20 m). The simulations assumed an 8-h working day with a break of 1 h. The models and statistics published by other studies were used to calculate the time consumption and number of work cycles completed within a working day. These data were used to compute the equivalent exposure to noise (LAeq) for each scenario, as well as for those work elements that were likely to expose the haulers to noise the most. The presented findings indicated that (i) the exposure to noise was higher than 100 dB(A), irrespective of variation in the considered factors; (ii) the trend in exposure was characterized by polynomials in relation to the extraction distance, and the magnitude of exposure was consistently affected by variation in the considered factors; and (iii) without hearing protection, the empty and loaded turns exposed workers to noise over the permissible limits. These findings strongly suggest the use of hearing protection when working in close proximity to sledge-based cable yarding operations. The methods proposed in this study in the form of simulation may help benchmark other forest operations.

Waste Heat Conversion to Power via Organic Rankine Cycle

several studies have been carried out on how to recover waste heat using Organic Rankine cycle. Each study applied different working conditions, power scale and cycle configuration, hence an assessment of working fluids is given for specific case. As a result, no single working fluid have been identified that would meet an entire heat source temperature levels. This motivated us to examine various substances for use as working fluids for subcritical ORC systems operating in the temperature range (543 - 633K). In this study, with a given finite thermal source, performance of working fluid candidates are evaluated and assessed using four criteria: thermal efficiency, exergy efficiency, total exergy destruction and net power output. Results of the study indicate that from a performance point of view, the linear alkanes such as nonane seem to be a suitable fluid in the temperature range (543-573K). Beyond aforementioned temperature range it appears that aromatic hydrocarbons such as toluene, ethylbenzene, P-xylene, O-xylene, propylbenzene preformed better. Under this condition, they represent comparably similar proposed screening criteria parameters and comparably high evaporating pressure, with only occasional slight differences between them.

Nightshift work and irregular menstrual cycle: 8-year follow-up cohort study.

Irregular menstruation is a major health problem among women, although its association with nightshift work remains controversial. To study the association between nightshift work and irregular menstrual cycle among female workers and investigate any differences according to sleep quality, working hours or obesity. This study included female workers who underwent health examinations from 2012 to 2019. Nightshift work, working hours, sleep quality and menstrual cycles were assessed using self-administered questionnaires. Irregular menstrual cycle was defined as self-reported irregular or ≥36 days. Adjusted odds ratios and 95% confidence intervals (CIs) were calculated by multivariable logistic regression; adjusted hazard ratios (95% CIs) for incident irregular menstrual cycle were calculated by Cox proportional hazard models with time-dependent analysis. The study participants were 87 147 in the cross-sectional study and 41 516 in the longitudinal study. After adjusting for all covariates in the cross-sectional analyses, the odds ratio for prevalent irregular menstrual cycle among female nightshift workers versus the reference was 1.26 (95% CI 1.2-1.33). In the cohort study, the adjusted hazard ratio for incident irregular menstrual cycle among nightshift workers was 1.95 (95% CI 1.61-2.35) in the period after 6 years. No significant differences were observed among subgroups stratified by sleep quality, working hours or obesity. Nightshift work is associated with an increased risk of both prevalent and incident irregular menstrual cycle in female workers without significant interactions by sleep quality, working hours or obesity.

The thermophysical properties of a promising composite adsorbent based on multi-wall carbon nanotubes for heat storage

AbstractThe use of energy from alternative energy sources as well as the use of waste heat are key elements of an efficient energetics. Adsorption heat storage is a technology that allows solving such problems. For the successful operation of an adsorption heat accumulator, it is necessary to analyze the thermophysical characteristics of the system under the conditions of the operating cycle: heat transfer coefficient adsorbent-metal (α2), overall (U) and global (UA) heat transfer coefficients of heat exchanger. Multi-walled carbon nanotube (MWCNT) composites are very promising for adsorption-based renewable energy storage and conversion technologies. In this work at the stage of heat release, α2 was measured by the large pressure jump (LPJ) method, at the stage of heat storage by large temperature jump method (LTJ), which made it possible to obtain thermophysical characteristics that corresponded to the implementation of the real working cycle as much as possible. The heat transfer coefficients for a pair of adsorbent LiCl/MWCNT—methanol are measured for the first time under the conditions of a daily heat storage cycle both at the sorption stage (α2 = 190 W/m2K) and at the desorption stage (α2 = 170 W/m2K).

Behavior of elastohydrodynamic lubricating film point contact problems in the unsteady state of reciprocating motion

Purpose In this study a numerical analysis of the elastohydrodynamic lubrication point contact problem in the unsteady state of reciprocating motion is presented. The effects of frequency, stroke length and load on film thickness and pressure variation during one operating cycle are discussed. The general tribological behavior of elastohydrodynamic lubrication during reciprocating motion is explained. Design/methodology/approach The system of equations of Reynolds, film thickness considering surface deformation and load balance equations are solved using the Newton-Raphson technique with the Gauss-Seidel iteration method. Numerical solutions were performed with a sinusoidal contact surface velocity to simulate reciprocating elastohydrodynamics. The methodology is validated using historical experimental measurements/observations and numerical predictions from other researchers. Findings The numerical results showed that the change in oil film during a stroke is controlled by both wedge and squeeze effects. When the surface velocity is zero at the stroke end, the squeeze effect is most noticeable. As the frequency increases, the general trend of central and minimum film thickness increases. With the same entraining speed but different stroke lengths, the properties of the oil film differ from one another, with an increase in stroke length leading to a reduction in film thickness. Finally, the numerical results showed that the overall film thickness decreases with increasing load. Originality/value General tribological behaviors of elastohydrodynamic lubricating point contact, represented by pressure and film thickness variations over time and profiles, are analyzed under reciprocating motion during one working cycle to show the effects of frequency, stroke length and applied load.

Artificial intelligence in healthcare: combining deep learning and Bayesian optimization to forecast COVID-19 confirmed cases.

Healthcare is a topic of significant concern within the academic and business sectors. The COVID-19 pandemic has had a considerable effect on the health of people worldwide. The rapid increase in cases adversely affects a nation's economy, public health, and residents' social and personal well-being. Improving the precision of COVID-19 infection forecasts can aid in making informed decisions regarding interventions, given the pandemic's harmful impact on numerous aspects of human life, such as health and the economy. This study aims to predict the number of confirmed COVID-19 cases in Saudi Arabia using Bayesian optimization (BOA) and deep learning (DL) methods. Two methods were assessed for their efficacy in predicting the occurrence of positive cases of COVID-19. The research employed data from confirmed COVID-19 cases in Saudi Arabia (SA), the United Kingdom (UK), and Tunisia (TU) from 2020 to 2021. The findings from the BOA model indicate that accurately predicting the number of COVID-19 positive cases is difficult due to the BOA projections needing to align with the assumptions. Thus, a DL approach was utilized to enhance the precision of COVID-19 positive case prediction in South Africa. The DQN model performed better than the BOA model when assessing RMSE and MAPE values. The model operates on a local server infrastructure, where the trained policy is transmitted solely to DQN. DQN formulated a reward function to amplify the efficiency of the DQN algorithm. By examining the rate of change and duration of sleep in the test data, this function can enhance the DQN model's training. Based on simulation findings, it can decrease the DQN work cycle by roughly 28% and diminish data overhead by more than 50% on average.

Dual phase change separator combining cooling and thermal shutdown functions for Li-ion battery with enhanced safety

The rapid growth of electric vehicles raises an unmet need to enhance high-temperature performance and safety of Li-ion battery (LIB). Herein, polyethylene glycol/polyvinylidene fluoride (PEG/PVDF) core @ polybutylene succinate (PBS) shell separator with cooling and thermal shutdown functions was fabricated using a one-step coaxial electrospinning method. The separator exhibited superior electrochemical performance even at room temperature due to good wettability and high porosity. When battery temperature rises as discharging, PEG with 50 °C melting point (m.p.) will melt to store heat temporarily. Thus, the separator with cooling function can effectively enhance ion conductivity to alleviate specific capacity drop and polarization voltage increase. As temperature decreases after battery discharging, the separator will release thermal energy to prepare for the next working cycle. When thermal runaway happens and raises temperate above 100 °C rapidly, the PBS shell will melt at 110 °C without skeleton thermal shrinkage. Separator pores can be blocked by the melted PBS and Li+ ions transfer can be inhibited in time to prevent disastrous consequence. Thus, dual phase change of the separator provides a novel and effective strategy for synergistic performance and safety enhancement of high temperature LIB.

Соціально-психологічне забезпечення сталого розвитку підприємства

Today's realities of economic development are associated with the strengthening of globalization, as well as innovation and integration processes, therefore the global society can be complementary characterized by an orientation towards ensuring sustainable development, which involves the harmonization of its economic, social and psychological components. International experience shows that, taking into account the conception of this process that should be aimed primarily at people and be carried out as a result of social and labor activities using their resources, sustainable development is possible only if there is a direct impact on work and the sociopsychological potential of society. The aim of the article is to study the principles, methods and tools of ensuring the sustainable development of the enterprise, using a sociopsychological complex of methods and techniques to ensure the professional activity of specialists at an optimal level, maintaining their functional state and capacity for work throughout the long working cycle. The set aim is achieved by consistently solving problems using dialectical, historical and logical approaches. The article presents the essence and parametric characteristics of the sustainable development of enterprise, with the aim of determining the level of efficiency of its functioning in accordance with modern development criteria. The contentual components of the conception of "sustainable development of enterprise" are defined through the prism of generally recognized components of sustainable development. Aspects of mutual coherence and effectiveness of enterprise functioning are considered through the prism of assessment, the sociopsychological aspectivity of the parametric characteristics of sustainable development. The practical significance lies in the formulation of proposals to ensure sustainable development of enterprise, primarily by means of the comprehensive use of a complex of social and psychological methods of ensuring a high level of professional activity, which is directly aimed at the specialist, his/her mental and physical health.

Longitudinal splitting of bunches with variable energies in synchrotron

The ever-enriching beam application has put for-ward more demands on accelerators. If multiple bunches of different energies can be extracted for FLASH point scanning in a short time (< 500 ms), the spatial dose distribution advantage of proton Bragg peak can be combined with the temporal effect ad-vantage of FLASH. This paper provides three methods for generating short bunches in synchrotron. By adjusting the pulse parameters of the barrier voltages in the induction synchrotron, the short bunches can be easily generated. The short bunches can be kicked out of the beam reference orbit by kickers. When the pro-cess is repeated for many times, and the energy-changing process is added to the time interval during which the short bunches are continuously generated, the short bunches of multiple energies can be extracted in one working cycle. By finely controlling the changes of rectangular pulses, the number of particles in the short bunches can be better controlled, making an important contribution to further enriching the application of synchrotron.

Focusing on Calibrating the Virtuous Cycle of Ideological and Political Psychological Work in Colleges and Universities in the New Era

Focusing on Calibrating the Virtuous Cycle of Ideological and Political Psychological Work in Colleges and Universities in the New Era

„Bamberger Zyklus“ von Albrecht von Eyb: die Schaffung der humanistischen Literatur in Deutschland um die Mitte des 15. Jahrhunderts

Albrecht von Eyb (1420–1475) — was a canon, lawyer, and writer, one of the first northern humanists of the 15th century. Eyb went down in the history of German literature primarily as the author of a treatise on marriage (Ehebüchlein, 1472) and as the first translator of Plautus’ comedies (part of Spiegel der Sitten, 1474). These significant works were preceded by the first humanist textbook of rhetoric written in Germany (Margarita poetica, 1459), which was the result of a 15-year stay in Italy and acquaintance with the humanist culture of the time. This article studies a cycle of Latin works (1451), Eyb’s first attempt at writing, which were later partially included in his Margarita. The four Latin opuscula, which I call here the ‘Bamberg Cycle’, were composed during Eyb’s one-year visit in Bamberg, when he was forced to interrupt his studies for a while to secure an income from his prebenda. The works of the cycle are united by the young author’s ambition to imitate humanist literature of his time, from which he borrows not only themes but also form. While it remains impossible to identify the precise audience for these works, or the reason that prompted Eyb to write them, a closer look at these works-exercises, which remain in the shadow of the author’s more successful works, allows us to trace the ways in which the ancient and humanist heritage was received and adapted. Thus, the works of the ‘cycle’ become important material not only for the study of Albrecht von Eyb’s writings, but also for the formation of humanist identity in mid-15th-century Germany, at a time when the institutionalisation of the movement and its further flourishing were only just emerging.

Towards improving the prognosis of stroke through targeting the circadian clock system.

Rhythmicity of the circadian system is a 24-hour period, driven by transcription-translation feedback loops of circadian clock genes. The central circadian pacemaker in mammals is located in the hypothalamic suprachiasmatic nucleus (SCN), which controls peripheral circadian clocks. In general, most physiological processes are regulated by the circadian system, which is modulated by environmental cues such as exposure to light and/or dark, temperature, and the timing of sleep/wake and food intake. The chronic circadian disruption caused by shift work, jetlag, and/or irregular sleep-wake cycles has long-term health consequences. Its dysregulation contributes to the risk of psychiatric disorders, sleep abnormalities, hypothyroidism and hyperthyroidism, cancer, and obesity. A number of neurological conditions may be worsened by changes in the circadian clock via the SCN pacemaker. For stroke, different physiological activities such as sleep/wake cycles are disrupted due to alterations in circadian rhythms. Moreover, the immunological processes that affect the evolution and recovery processes of stroke are regulated by the circadian clock or core-clock genes. Thus, disrupted circadian rhythms may increase the severity and consequences of stroke, while readjustment of circadian clock machinery may accelerate recovery from stroke. In this manuscript, we discuss the relationship between stroke and circadian rhythms, particularly on stroke development and its recovery process. We focus on immunological and/or molecular processes linking stroke and the circadian system and suggest the circadian rhythm as a target for designing effective therapeutic strategies in stroke.