Continuous Regime Research Articles

Characterization of Properties of 325-MHz Half-Wave Superconducting Resonators at Low Microwave Field Amplitudes

A prototype of the 325-MHz niobium half-wave coaxial resonator (\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\beta = 0.21$$\\end{document}) is developed, built, and tested at low microwave field amplitudes. Electromagnetic properties of the prototype in the superconducting state are investigated in the continuous wave regime and the damping regime using a highly stable radio-frequency (RF) generator and power detectors. The experimental data on the resonator’s response in the superconducting state are used to calculate its most important characteristics—the intrinsic Q value and the accelerating field. The experimentally measured Q value of the prototype is \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{Q}_{0}} = (3.5 \\pm 0.1) \ imes {{10}^{8}}$$\\end{document} at input powers of up to +20 dBm.

Construction and evaluation of electrophotocataltic tubular reactor in phenol degradation

Contamination of the environment is one of the main threats to achieving sustainability. Even though there have been significant legal efforts to regulate parameters for effluent disposal, conventional treatment methods often prove to be ineffective, resulting in the incomplete removal of pollutants. This inefficiency leads to serious environmental issues, such as the toxicity of biomes, which is closely related to the bioaccumulation of harmful substances. In response to this challenge, this study aimed to develop and optimize an electrophotocatalytic reactor for the remediation of a synthetic phenol solution using advanced oxidative processes (AOPs). By applying these processes, we observed that the characteristics of the reaction medium allowed for a maximum pollutant removal yield of 54.73% over a 3-hour operation period in a continuous recirculation regime. Despite the promising results, the study revealed the influence of additional factors that were not considered, which are likely important in further optimizing the reactor's efficiency for real-world applications.

Influence of Rarefaction Degree and Aft-Body Geometry on Supersonic Flows

During atmospheric entry, super-/hypersonic vehicles cross distinct atmospheric layers characterized by large density variations and thus experience different flow regimes ranging from free molecular, transition, slip, to continuous regimes. Due to the distinct modeling strategy between these regimes and complex physical phenomena appearing near the vehicles (boundary-layer/shock interaction, base-flow recirculation, etc.), assessing their aerodynamic properties may be difficult. The present work focuses on supersonic flows around sharp-base geometries in both continuous and slip-flow regimes and aims at highlighting the influence of both rarefaction degree and base geometry on the vehicles’ aerodynamic features. For this purpose, three axisymmetric cone-cylinder geometries with right-angled, rounded, or flared rear parts are considered. Flow visualization, pressure, and drag measurements are carried out at Mach number Ma=4 and Knudsen numbers ranging from Kn=4×10−4 to 1×10−2 in the supersonic rarefied MARHy wind tunnel. The experimental data are compared with numerical results of simulations performed with a continuous-flow Navier–Stokes (NS) solver and two rarefied flows codes: a discrete-ordinate Bhatnagar–Gross–Krook (K) solver and a direct simulation Monte Carlo (SPARTA) solver. While the NS solver overestimates frictional drag as Kn rises, the rarefied K and SPARTA results show satisfactory agreement with experimental data. The latter numerical results highlight the main effects of rarefaction: as Kn increases, shocks become more diffuse, skin friction strengthens (leading to a significant increase in drag coefficients), and the extent of the base-recirculation decreases. Regarding the aft-body geometry, its influence on the base recirculation vanishes with increasing Kn.

Emulating the Delivery of Sawtooth Proton Arc Therapy Plans on a Cyclotron-Based Proton Beam Therapy System

Purpose: To evaluate and compare the deliverability of ‘sawtooth’ proton arc therapy (PAT) plans relative to static intensity modulated proton therapy (IMPT) at a cyclotron-based clinical facility. Methods: The delivery of single and dual arc Sawtooth PAT plans for an abdominal CT phantom and multiple clinical cases of brain, head and neck (H&N) and base of skull (BoS) targets was emulated under the step-and-shoot and continuous PAT delivery regimes and compared to that of a corresponding static IMPT plan. Results: Continuous PAT delivery increased the time associated with beam delivery and gantry movement in single/dual PAT plans by 4.86/7.34 min (brain), 7.51/12.40 min (BoS) and 6.59/10.57 min (H&N) on average relative to static IMPT. Step-and-shoot PAT increased this delivery time further by 4.79 min on average as the delivery was limited by gantry motion. Conclusions: The emulator can approximately model clinical sawtooth PAT delivery but requires experimental validation. No clear benefit was observed regarding beam-on time for sawtooth PAT relative to static IMPT.

Multivariate post‐processing of probabilistic sub‐seasonal weather regime forecasts

AbstractReliable forecasts of quasi‐stationary, recurrent, and persistent large‐scale atmospheric circulation patterns—so‐called weather regimes—are crucial for various socio‐economic sectors, including energy, health, and agriculture. Despite steady progress, probabilistic weather regime predictions still exhibit biases in the exact timing and amplitude of weather regimes. This study thus aims at advancing probabilistic weather regime predictions in the North Atlantic–European region through ensemble post‐processing. Here, we focus on the representation of seven year‐round weather regimes in sub‐seasonal to seasonal reforecasts of the European Centre for Medium‐Range Weather Forecasts (ECMWF). The manifestation of each of the seven regimes can be expressed by a continuous weather regime index, representing the projection of the instantaneous 500‐hPa geopotential height anomalies (A) onto the respective mean regime pattern. We apply a two‐step ensemble post‐processing involving first univariate ensemble model output statistics and second ensemble copula coupling, which restores the multivariate dependence structure. Compared with current forecast calibration practices, which rely on correcting the field by the lead‐time‐dependent mean bias, our approach extends the forecast skill horizon for daily/instantaneous regime forecasts moderately by 1 day (from 13.5 to 14.5 days). Additionally, to our knowledge our study is the first to evaluate the multivariate aspects of forecast quality systematically for weather regime forecasts. Our method outperforms current practices in the multivariate aspect, as measured by the energy and variogram score. Still, our study shows that, even with advanced post‐processing, weather regime prediction becomes difficult beyond 14 days, which likely points towards intrinsic limits of predictability for daily/instantaneous regime forecasts. The proposed method can easily be applied to operational weather regime forecasts, offering a neat alternative for cost‐ and time‐efficient post‐processing of real‐time weather regime forecasts.

An insight in to microwave induced defects and its impact on nonlinear process in NiO nanostructures under femtosecond and continuous wave laser excitation.

This work demonstrates the impact of microwave (MW) irradiation on third-order nonlinear optical (NLO) processes in chemically deposited NiO nanostructure films. The optical nonlinearity of the NiO nanostructure films was studied using third-harmonic generation (THG) measurements in the pulsed femtosecond laser regime and the Z-scan technique in the continuous wave laser regime. In the ultrafast pulsed regime, THG measurements revealed a significant increase in the THG signal of MW-irradiated NiO nanostructures due to photoexcitation and relaxation processes, resulting from an enhancement in defect concentration. This increase in defect density upon MW irradiation was quantified by PL and XPS studies. Under continuous wave laser irradiation, the Z-scan technique showed an enhanced absorption coefficient of ∼10-1 m W-1 and a nonlinear refractive index of ∼10-7 m2 W-1. The high NLO values in both pulsed and continuous laser regimes indicate that MW-irradiated NiO nanostructure films hold promise for optoelectronic device applications.

Integrated analysis of the Neogene–Quaternary Valdera‐Volterra Basin (Northern Apennines). Evidence for composite development of hinterland basins

AbstractThe Neogene and Quaternary hinterland basins of the Northern Apennine have been the subject of different tectonic interpretations. Several studies considered these basins as the result of polyphase normal faulting framed in a continuous crustal extensional regime since the middle Miocene. On the contrary, geophysical and geological studies provided evidence of the important role played by out‐of‐sequence thrusts and backthrusts in the evolution of these basins during a prolongated and intense period of shortening. Here we present an integrated analysis of 2D stacked seismic reflection profiles, stratigraphic and geophysical data from deep exploration wells, gravity data, and published geological and biostratigraphic data for the Valdera‐Volterra basin (central Tuscany, Italy). The results support a polyphase and composite evolution of the basin, subdivided into three main phases. During the late Tortonian–Zanclean, the growth of major thrust‐related anticlines controlled the evolution of the sedimentary basin. The growth of a syncline determined the creation of accommodation space for the sediments. This main compressional deformation occurred during the Messinian and ended during the Late Zanclean. NE migration of the depocentre during the Early Zanclean was identified, likely possibly due to a differential activity growth between the bordering anticlines. During the Piacenzian, an extensional phase has been recognised, superposed to the previous compressive phase. During the Latest Piacenzian–Early Pleistocene (?), a final compressional phase took place resulting in the positive inversion of the Piacenzian WSW dipping main border fault.

Mathematical derivation of a unified equations for adjoint lattice Boltzmann method in airfoil and wing aerodynamic shape optimization

Unified equations of the adjoint lattice Boltzmann method (ALBM) are derived for five applicable objective functions in 2D/3D aerodynamic shape optimization problems. The derived equations include the adjoint equation, boundary condition, terminal condition and gradient of the cost function. In this research, firstly, these relations are extracted for each objective in details and then the general form of ALBM equations are presented for all defined practical aerodynamic objective function. Five applicable cost functions which are the most important objectives in optimization of aerodynamic geometries include desired pressure and viscous shear stress (VSS) inverse design, drag and moment at fixed lift and finally lift to drag ratio at fixed angle of attack. The new extracted relations are based on the circular and spherical function scheme, and are valid for viscous/inviscid, compressible/incompressible and 2D/3D flows in all continuous flow regimes. Proof of new extracted general relations have been performed by authors.

Analysis of membrane fouling during microfiltration of copper sulfide precipitates

Membrane filtration, particularly MF-UF, has previously been assessed as an attractive process for clarifying and recovering valuable metals from metal sulfide precipitation. Previous results of the high transmembrane flux achieved have shown to be promising. However, those studies were primarily focused on demonstrating the method’s feasibility and estimating its performance under different operational conditions. Based on that, this study represents a significant advancement in the field, assessing the fouling behavior and its impact on process performance during the microfiltration of metal sulfide precipitates. Different operational conditions were evaluated using commercial microfiltration membranes operating in batch and continuous regimes, varying Cu concentration in the feed solution (200 and 1800 mg/L), and cross-flow velocities (0.2 – 0.16 m/s). Batch recirculation tests had over 80 % better flux results than the long-term continuous-mode operation tests, mainly due to a progressive decline in the membrane flux observed at longer operation times.Moreover, the cross-flow velocity evaluation indicated that elevated tangential flow rates might result in a decline in the performance of particles with high aggregation behavior. Analyses with modified Hermia’s models and with SEM-EDX image characterizations demonstrated that cake filtration represents the primary fouling mechanism in this process under long-term operation. The present study offers crucial insights that will inform the further development of MF for the treatment of metal sulfide precipitates.

New spin coated multilayer lactate biosensor for acidosis monitoring in continuous flow assisted with an electrochemical pH probe

A LOx-based electrochemical biosensor for high-level lactate determination was developed. For the construction of the biosensor, chitosan and Nafion layers were integrated by using a spin coating procedure, leading to less porous surfaces in comparison with those recorded after a drop casting procedure. The analytical performance of the resulting biosensor for lactate determination was evaluated in batch and flow regime, displaying satisfactory results in both modes ranging from 0.5 to 20 mM concentration range for assessing the lactic acidosis. Finally, the lactate levels in raw serum samples were estimated using the biosensor developed and verified with a blood gas analyzer. Based on these results, the biosensor developed is promising for its use in healthcare environment, after its proper miniaturization. A pH probe based on common polyaniline-based electrochemical sensor was also developed to assist the biosensor for the lactic acidosis monitoring, leading to excellent results in stock solutions ranging from 6.0 to 8.0 mM and raw plasma samples. The results were confirmed by using two different approaches, blood gas analyzer and pH-meter. Consequently, the lactic acidosis monitoring could be achieved in continuous flow regime using both (bio)sensors.

Decreased activity in zebrafish larvae exposed to glyphosate-based herbicides during development-potential mediation by glucocorticoid receptor.

Glyphosate-based herbicides (GBH) are a widely used group of pesticides that have glyphosate (GLY) as main active compound and are used to control a wide range of weeds. Experimental and epidemiological studies point to neurotoxicity and endocrine disruption as main toxic effects. The aim of this study was to investigate the effects of developmental exposure to GLY and GBH on locomotor behavior, and the possible contribution of GR-mediated signaling. We used zebrafish (Danio rerio) larvae in a continuous exposure regimen to GLY or GBH in the rearing medium. Alongside TL wildtype, we used a mutant line carrying a mutation in the GR which prevents the GR from binding to DNA (grs357), as well as a transgenic strain expressing a variant of enhanced green fluorescent protein (d4eGFP) controlled by a promoter carrying multiple GR response elements (SR4G). We found that acute exposure to GBH, but not GLY, activates GR-mediated signaling. Using a continuous developmental exposure regime, we show that wildtype larvae exposed to GBH display decreased spontaneous activity and attenuated response to environmental stimuli, a pattern of alteration similar to the one observed in grs357 mutant larvae. In addition, developmental exposure to GBH has virtually no effects on the behavior of grs357 mutant larvae. Taken together, our data indicate that developmental exposure to GBH has more pronounced effects than GLY on behavior at 5 dpf, and that interference with GR-mediated signaling may have a relevant contribution.

Dynamics of the material ejection in a dipolar arc in continuous regime

Electrical and fast imaging measurements are performed on an experimental device designed to study the dynamics of electric arcs in the DC regime. The work presented here investigates the relationship between electrical fluctuations and material ejection from the electrode surface. Cross-analysis of the electrical and imaging data reveals a significant correlation between electrical fluctuations in the kHz range and particle emission from the electrode surface. Different types of ejection are presented and a study of the dynamics of the ejected particles is carried out through the analysis of a statistically significant number of trajectories.

Oral infections - a retrospective study of patients treated in the Oral and Maxillofacial Surgery clinic of the Emergency County Clinical Hospital in Sibiu.

The present study was carried out in the Department of Oral and Maxillo-Facial Surgery of the Sibiu County Emergency Clinical Hospital and aimed to evaluate the oral health status of patients who refer to this medical unit, identifying the presence and frequency of dental infections among these patients. The study also aimed to identify and characterize the comorbidities present in patients with these oral conditions. Finally, the study aims to highlight the degree of concern regarding the oral health status of patients and provide relevant information for dental health services and for the development of appropriate prevention and intervention strategies. The study was conducted retrospectively and descriptively, using the hospital's electronic medical records. The total sample consisted of 1246 people, the inclusion criteria were: (a) patients admitted to the OMF Surgery Department; (b) outpatients who required hospitalization; (c) patients hospitalized under continuous hospitalization regime; (d) patients over 16 years of age; (e) patients diagnosed with infectious pathologies.After data registration, information on sex, background, distribution of diagnoses, associated pathologies of the patients and the existence of combined pathologies of the patients included in the study were taken into account. The duration of hospitalization of patients, the need and duration of antibiotic therapy, the frequency of use of combinations of antibiotics, and the number of antibiotics used in correlation with the duration of hospitalization were also analyzed.The data are presented as frequency and percentages. The combination of the most frequent associated pathologies was analyzed using an algorithm based on association rules and chord diagram was used for their visual representation. Statistical analyses were performed using IBM SPSS® (Statistical Package for the Social Science) version 20 and R software. The total sample consisted of a total of 1246 people. From the preliminary analysis, the majority of people in the sample, 68.5%, did not suffer from infectious conditions, while 31.5% were affected. Most of the patients came from the urban environment (61.73%) and were male (54.34%). Frequent comorbidities included cardiac pathologies (11.99%) and diabetes (4.08%).These data indicate the poor state of oral health among patients who call on the OMF Surgery services. It is not an isolated case, but it reflects a pattern observed globally. Based on the results of the study, the hypothesis is validated that there is a poor state of oral health among the population, manifested by the increased incidence of dental infections. International studies confirm that dental infections are often complicated by the presence of comorbidities. The study concludes that patients hospitalized in the department of Oral and Maxillofacial Surgery face a poor oral health state, characterized by a high prevalence of dental infections. The presence of comorbidities and seasonal factors contribute to the aggravation of these infections. These results emphasize the need for preventive and educational interventions to improve the oral health of the population in this region, as well as the development of personalized treatment strategies.

Continuous Rifampicin Therapy Induced Acute Kidney Injury in a Tuberculous Patient: A Case Report

Background: Tuberculosis (TB) presents with productive cough, hemoptysis, chest pain, fever, weight loss, and night sweats. Anti-tuberculosis treatment (ATT) can affect various organs, including the liver and kidneys. ATT-induced acute kidney injury (AKI) presents with fever, rash, nausea, vomiting, diarrhea, and abdominal pain. It occurs due to type 2 or 3 hypersensitivity and affects individuals who have previously used rifampicin or are currently using it intermittently. Case: An 60-year-old lady was diagnosed with TB and started on ATT. After a few days, she complained of reduced food intake and vomiting, yellow discoloration of the skin, abdominal pain and distention, and limb swelling. She was diagnosed as a case of ATT-induced AKI. She didn't have past exposure to rifampicin and was continuously using it this time. Conclusion: The key learning point from this case is that ATT-induced AKI can develop even when used in a continuous dosing regime and upon first time exposure despite no history of past exposure. This prompts vigilance in monitoring renal function in patients being started on ATT regimen. This is becasuse, ATT-induced AKI poses risk to patient’s life and there is a possibility of developing resistance to anti-tuberculous therapy as a result of discontinuation of treatment. Furthermore, our case suggests that, in addition to immune-mediated mechanisms described in literature for ATT-induced AKI, other pathophysiological mechanisms might also be linked to this pathology and need further research for better understanding and optimization of treatment strategies.

Abandonment or biomass production? Phytodiversity responses to land-use changes of semi-natural grasslands in northern Europe

European semi-natural grasslands are hotspots for biodiversity and important for the provisioning of multiple ecosystem services, but their extent has declined considerably during the past century. Increasing demands for agricultural and forest biomass risk causing further loss of grasslands, raising concern about a goal conflict between climate mitigation and biodiversity conservation. This study focused on the loss of semi-natural grasslands in a mixed farm-forest landscape in southern Sweden by comparing plant diversity in grasslands with continuous grazing regimes to recently abandoned grasslands, improved grasslands (sown leys), and afforested grasslands. Compared to actively grazed grasslands, grasslands where grazing had been abandoned showed a lower plant species richness and fewer plant species of conservation concern, but similar species composition. In contrast, both improved and afforested grasslands showed >50 % lower species richness than abandoned and grazed grasslands, with profoundly different species composition. The dissimilarity in plant diversity between sites was primarily driven by the replacement of species (turnover), and trait-based analyses indicated that environmental filtering of light, management, and nutrient requirements of plants shaped the community differences. Furthermore, an increased cover of semi-natural grassland around the sites positively related to plant species richness and diversity, while an increased cropland coverage around the sites showed a negative relationship. Our results emphasize the importance of integrated land-use strategies that prioritize biodiversity conservation in mixed farm-forest landscapes, such as restoration of semi-natural grasslands and strategic planning of biomass production to avoid serious biodiversity losses.

Additive and geometric transversality of fractal sets in the integers

AbstractBy juxtaposing ideas from fractal geometry and dynamical systems, Furstenberg proposed a series of conjectures in the late 1960's that explore the relationship between digit expansions with respect to multiplicatively independent bases. In this work, we introduce and study — in the discrete context of the integers — analogs of some of the notions and results surrounding Furstenberg's work. In particular, we define a new class of fractal sets of integers that parallels the notion of ‐invariant sets on the 1‐torus and investigate the additive and geometric independence between two such fractal sets when they are structured with respect to multiplicatively independent bases. Our main results in this direction parallel the works of Furstenberg, Hochman–Shmerkin, Shmerkin, Wu, and Lindenstrauss–Meiri–Peres and include: a classification of all subsets of the positive integers that are simultaneously ‐ and ‐invariant; integer analogs of two of Furstenberg's transversality conjectures pertaining to the dimensions of the intersection and the sumset of ‐ and ‐invariant sets and when and are multiplicatively independent; and a description of the dimension of iterated sumsets for any ‐invariant set . We achieve these results by combining ideas from fractal geometry and ergodic theory to build a bridge between the continuous and discrete regimes. For the transversality results, we rely heavily on quantitative bounds on the ‐dimensions of projections of restricted digit Cantor measures obtained recently by Shmerkin. We end by outlining a number of open questions and directions regarding fractal subsets of the integers.

Hyperspectral optical orbital angular momentum modulation from tunable structured waveplates.

Shaping the orbital angular momentum of optical pulses in the spectral domain is a means of managing light in space and time that offers many possible applications. However, these are limited by the small number of techniques available, whose flexibility does not yet rival that of the continuous regime. We propose here to implement a tunable hyperspectral management of the orbital angular momentum of a polychromatic light field. The main idea is to exploit the dispersive nature of geometric phase optical elements by intentionally choosing to work in a regime of high anisotropic optical retardance. An experimental proof of principle is demonstrated in the visible range using a supercontinuum laser and an optically thick, electrically controllable, liquid crystal structured wave plate.

Mechanistic Studies of Continuous Partial Methane Oxidation on Cu−Zeolites Using Kinetic and Spectroscopic Methods

AbstractOver the past few decades, a significant amount of research effort has focused on investigating the active site requirements and reaction mechanisms for partial methane oxidation (PMO) to methanol over copper–exchanged zeolites during stoichiometric and stepwise chemical looping routes. More recently, research efforts have expanded to include investigating the PMO reaction in a continuous catalytic regime, primarily focusing on determining the influence of catalyst composition on Cu speciation and structure and, in turn, on PMO rate and selectivity. The structures of candidate Cu active sites are commonly studied using a combination of ex situ and in situ spectroscopic approaches. In this perspective, we critically examine the prior literature on catalytic PMO over Cu–zeolites to identify key knowledge gaps that remain in our understanding as motivation for future research efforts. We identify opportunities for future research to address these gaps by adapting analogous interrogation techniques that have been successfully used to elucidate the active site requirements and mechanistic details of another catalytic redox reaction cycle on Cu–zeolites, the selective catalytic reduction (SCR) of nitrogen oxides (NOx).

Особенности использования кластерного подхода при организации государственно-частного партнерства в сфере туризма

The study of the features of using the cluster approach in organizing public-private partnerships in the field of tourism is highly relevant in the context of the continued sanctions regime against Russia by the United States and the European Union. This is due, on the one hand, to the multiple growth of domestic tourism in many regions of Russia, and on the other, to high geopolitical risks and limited financial resources of Russian business. The article describes the dynamics of the development of public-private partnerships and its organizational features in the Russian Federation. In particular, the absolute priority of the share of concession agreements in the overall structure of public-private partnership projects in 2022 is shown; the structural differences between the initiatives of public-private partnership projects in Europe and the Russian Federation in 2020-2022 are identified, as well as the national characteristics of public-private partnerships in relation to the tourism complex, the organization of which is still a poorly developed method of improving national tourism. A significant difference between a domestic organization and a foreign one is that in Russia tourism is considered as a separate sector, while in Europe public-private partnership projects indirectly influence the improvement of tourism in the regions through the development of transport and social infrastructures. Whereas in Russia, in addition to projects of indirect importance, much attention is paid to potentially useful objects for increasing direct endogenous tourism indicators, such as the number of tourist arrivals, the number of foreign arrivals, increasing the share of tourism in GDP, passenger traffic, etc. It is concluded that a characteristic feature of the development of the tourism complex in the public-private partnership (PPP) format can be considered the use of the cluster approach as the main one. This allowed the authors to reveal a set of advantages of PPP in tourism; formulate the characteristics of a tourism cluster formed through the association of representatives of government agencies and private business; propose a scheme for the effectiveness of PPP design in tourism using a cluster approach.

Operation of a Ramsey-CPT microcell atomic clock with driving current-based power modulation of a VCSEL

We report on the operation of a coherent population trapping (CPT) microcell atomic clock using a pulsed Ramsey-like interrogation. The Ramsey-CPT sequence, defined by two-step optical pulses separated by a free-evolution dark time, is produced by switching on and off the output power of a low-power vertical-cavity surface-emitting laser, through direct modulation of its driving current. High-contrast and narrow Ramsey-CPT fringes are detected without the use of any external optical modulator stage. We demonstrate closed-loop operation of the clock based on high-speed digital signal processing implemented in a field programmable gate array board. The clock's short-term fractional frequency stability is 1.3 × 10−10τ−1/2 until 2000 s. A power light-shift coefficient of 8 × 10−11/μW, in relative value, is obtained for a dark time of 150 μs. This value is about ten times lower than in the continuous regime. These results show the feasibility of fully integrated atomic clocks based on Ramsey spectroscopy, which could provide enhanced long-term stability.