Variations of hydrogen in the surface-atmosphere in connection with the manifestation of seismic activity in the Eastern Caucasus

According to the literature, modern ideas about the earthquake center as one of the blocks of the hierarchical structure of the earth's crust, which loses stability during energy and mass exchange with the environment, are considered. Long-term continuous measurements (6 years) of hydrogen concentrations in the surface-atmosphere were carried out at two observation points in the Dagestan wedge tectonic region (Republic of Dagestan). It is shown that variations of hydrogen concentrations in the surface-atmosphere have annual periodicity. At the same time, in adjacent time intervals of the series, a change in the dispersion of hydrogen concentrations is noted. Initially, there is an increase in the value of the dispersion, after which it is marked by an abrupt decrease, the stages of which in most cases correspond to seismic events. A change in the dispersion value in adjacent time intervals of hydrogen concentrations implies a corresponding change in the entropy in the exciting thermodynamic system, i.e. in the earthquake focus. As a result of the relaxation of elastic energy, the thermodynamic system passes to the most probable, steady-state, and accordingly, values of dispersion of concentrations of hydrogen tend to a minimum.

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Steady-State Analysis of the Join-the-Shortest-Queue Model in the Halfin–Whitt Regime

Mathematics of Operations Research ◽

10.1287/moor.2019.1023 ◽

2020 ◽

Vol 45 (3) ◽

pp. 1069-1103

Author(s):

Anton Braverman

Keyword(s):

Steady State ◽

Diffusion Limit ◽

Fluid Limit ◽

Time Intervals ◽

Dimensional Diffusion ◽

Queue Model ◽

Join The Shortest Queue ◽

Shortest Queue ◽

Process Level ◽

General Tool

This paper studies the steady-state properties of the join-the-shortest-queue model in the Halfin–Whitt regime. We focus on the process tracking the number of idle servers and the number of servers with nonempty buffers. Recently, Eschenfeldt and Gamarnik proved that a scaled version of this process converges, over finite time intervals, to a two-dimensional diffusion limit as the number of servers goes to infinity. In this paper, we prove that the diffusion limit is exponentially ergodic and that the diffusion scaled sequence of the steady-state number of idle servers and nonempty buffers is tight. Combined with the process-level convergence proved by Eschenfeldt and Gamarnik, our results imply convergence of steady-state distributions. The methodology used is the generator expansion framework based on Stein’s method, also referred to as the drift-based fluid limit Lyapunov function approach in Stolyar. One technical contribution to the framework is to show how it can be used as a general tool to establish exponential ergodicity.

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Comparison of dynamic programming policies for long-term hydrothermal scheduling of single-reservoir systems in steady-state regime

Electric Power Systems Research ◽

10.1016/j.epsr.2021.107275 ◽

2021 ◽

Vol 196 ◽

pp. 107275

Author(s):

Thayze D’Martin Costa ◽

Secundino Soares

Keyword(s):

Dynamic Programming ◽

Steady State ◽

Steady State Regime ◽

Hydrothermal Scheduling ◽

Reservoir Systems ◽

State Regime

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Debridement, Antibiotics, and Implant Retention Is a Viable Treatment Option for Early Periprosthetic Joint Infection Presenting More Than 4 Weeks After Index Arthroplasty

Clinical Infectious Diseases ◽

10.1093/cid/ciz867 ◽

2019 ◽

Vol 71 (3) ◽

pp. 630-636 ◽

Cited By ~ 3

Author(s):

Claudia A M Löwik ◽

Javad Parvizi ◽

Paul C Jutte ◽

Wierd P Zijlstra ◽

Bas A S Knobben ◽

...

Keyword(s):

Treatment Failure ◽

Periprosthetic Joint Infection ◽

Joint Infection ◽

Viable Option ◽

Time Intervals ◽

Implant Retention ◽

Time Point ◽

Viable Treatment

Abstract Background The success of debridement, antibiotics, and implant retention (DAIR) in early periprosthetic joint infection (PJI) largely depends on the presence of a mature biofilm. At what time point DAIR should be disrecommended is unknown. This multicenter study evaluated the outcome of DAIR in relation to the time after index arthroplasty. Methods We retrospectively evaluated PJIs occurring within 90 days after surgery and treated with DAIR. Patients with bacteremia, arthroscopic debridements, and a follow-up <1 year were excluded. Treatment failure was defined as (1) any further surgical procedure related to infection; (2) PJI-related death; or (3) use of long-term suppressive antibiotics. Results We included 769 patients. Treatment failure occurred in 294 patients (38%) and was similar between time intervals from index arthroplasty to DAIR: the failure rate for Week 1–2 was 42% (95/226), the rate for Week 3–4 was 38% (143/378), the rate for Week 5–6 was 29% (29/100), and the rate for Week 7–12 was 42% (27/65). An exchange of modular components was performed to a lesser extent in the early post-surgical course compared with the late course (41% vs 63%, respectively; P < .001). The causative microorganisms, comorbidities, and durations of symptoms were comparable between time intervals. Conclusions DAIR is a viable option in patients with early PJI presenting more than 4 weeks after index surgery, as long as DAIR is performed within at least 1 week after the onset of symptoms and modular components can be exchanged.

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Long-term repopulating hematopoietic stem cells and “side population” in human steady state peripheral blood

Stem Cell Research ◽

10.1016/j.scr.2013.04.003 ◽

2013 ◽

Vol 11 (1) ◽

pp. 625-633 ◽

Cited By ~ 16

Author(s):

Philippe Brunet de la Grange ◽

Marija Vlaski ◽

Pascale Duchez ◽

Jean Chevaleyre ◽

Veronique Lapostolle ◽

...

Keyword(s):

Stem Cells ◽

Steady State ◽

Hematopoietic Stem Cells ◽

Peripheral Blood ◽

Side Population ◽

Hematopoietic Stem

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Annual hazard rates of recurrence for breast cancer after primary therapy.

Journal of Clinical Oncology ◽

10.1200/jco.1996.14.10.2738 ◽

1996 ◽

Vol 14 (10) ◽

pp. 2738-2746 ◽

Cited By ~ 592

Author(s):

T Saphner ◽

D C Tormey ◽

R Gray

Keyword(s):

Breast Cancer ◽

Eastern Cooperative Oncology Group ◽

Entire Group ◽

Hazard Rates ◽

Primary Therapy ◽

Time Intervals ◽

Differentiating Agents ◽

The Mean ◽

Lower Hazard

PURPOSE To determine if the long-term increase of recurrence for breast cancer is stable or slowly decreasing, or if it ever reaches zero; and to determine the effect of prognostic factors on the hazard of recurrence. METHODS All patients entered onto the seven completed and unblinded Eastern Cooperative Oncology Group (ECOG) coordinated studies of postoperative adjuvant therapy for breast cancer were analyzed in terms of annual hazard of recurrence of breast cancer. RESULTS For the entire group, the peak hazard of recurrence occurred in the interval of 1 to 2 years. The hazard decreased consistently in the interval of 2 to 5 years. Beyond 5 years, the hazard of recurrence decreased very, very slowly through year 12. The average hazard of recurrence between years 5 and 12 for the entire population was 4.3% per year. The pattern of a peak hazard of recurrence during the first 5 years with a slowly decreasing hazard of recurrence beyond 5 years was also observed to varying degrees in most subsets. Higher risk subsets such as patients with more than three nodes positive had a higher hazard of recurrence at all time intervals, while lower risk subsets such as patients with negative nodes had a lower hazard of recurrence in all time periods. CONCLUSION Patients 5 years postsurgery for breast cancer appear to have a very slowly decreasing hazard of recurrence. The mean hazard of recurrence between years 5 to 12 postsurgery is 4.3% per year. This group of patients may be well suited for trials evaluating cytostatic drugs or differentiating agents.

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Effects of Accelerated Aging Period of Time at 180°C on Tensile Property of Plain Woven Fabric/Epoxy Resin Laminated Composites

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.182-183.76 ◽

2012 ◽

Vol 182-183 ◽

pp. 76-79 ◽

Cited By ~ 1

Author(s):

Lei Lei Song ◽

Quan Rong Liu ◽

Jia Lu Li

Keyword(s):

Tensile Strength ◽

Carbon Fiber ◽

Epoxy Resin ◽

Laminated Composites ◽

Accelerated Aging ◽

Woven Fabric ◽

Accelerated Ageing ◽

Time Intervals ◽

Composite Samples

In this paper, carbon fiber reinforced resin matrix composites were produced by stacking eight pieces of carbon fiber woven plain fabric and subjected to accelerated ageing. Accelerated ageing was carried out in oven at 180°C for three different time intervals (60 hours, 120 hours and 180 hours). The influence of different ageing time intervals at 180°C on tensile properties of laminated composites was examined, compared with the composites without aging. The appearance and damage forms of these laminated composites were investigated. The results revealed that the tensile strength of the laminates declined significantly after long term accelerated aging at 180°C. The average tensile strengths of composite samples aged 60 hours, 120 hours, and 180 hours period of time at 180°C are 80.36%, 79.82%, 76.57% of average tensile strength of composite samples without aging, respectively. The high temperature accelerated aging makes the resin macromolecular structure in the composites changed, and then the adhesive force between fiber bundles and resin declines rapidly which result in the tensile strength of composites aged decrease. This research provides a useful reference for long term durability of laminated/epoxy resin composites.

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Predictive value of glucose tolerance test

Kazan medical journal ◽

10.17816/kazmj59774 ◽

1982 ◽

Vol 63 (1) ◽

pp. 18-19

Author(s):

V. G. Baranov

Keyword(s):

Glucose Tolerance ◽

Tolerance Test ◽

Normal Glucose Tolerance ◽

Time Intervals ◽

Glucose Content ◽

Glucose Loading ◽

Normal Glucose ◽

Risk Zones ◽

Long Term Observation

Abstract. A retrospective analysis of the long-term observation of the dynamics of normal glucose tolerance in 564 women was carried out. Re-examination revealed violations of tolerance in 33.8% (of doubtful type in 25.7% and of diabetic type in 8.1%). An unfavorable prognostic value of the blood glucose content after glucose loading was established after 1 hour - from 7.8 mmol / L and more and after 2 hours - from 6.1 mmol / L or more. It is proposed to consider these levels as the limit of normoglycemia at the indicated time intervals when conducting a test for glucose tolerance. Glycemia from 7.8 to 9.9 mmol / L 1 hour after glucose loading and from 6.1 to 7.2 mmol / L after 2 hours are regarded by the authors as risk zones for diabetes mellitus.

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Temporal Evolution of Immunity Distributions in a Population with Waning and Boosting

Complexity ◽

10.1155/2018/9264743 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13

Author(s):

M. V. Barbarossa ◽

M. Polner ◽

G. Röst

Keyword(s):

Mathematical Model ◽

Steady State ◽

Temporal Evolution ◽

Disease Outbreaks ◽

Population Level ◽

Coupled System ◽

Disease Outbreak ◽

Periodic Disease ◽

Evolution Of Immunity

We investigate the temporal evolution of the distribution of immunities in a population, which is determined by various epidemiological, immunological, and demographical phenomena: after a disease outbreak, recovered individuals constitute a large immune population; however, their immunity is waning in the long term and they may become susceptible again. Meanwhile, their immunity can be boosted by repeated exposure to the pathogen, which is linked to the density of infected individuals present in the population. This prolongs the length of their immunity. We consider a mathematical model formulated as a coupled system of ordinary and partial differential equations that connects all these processes and systematically compare a number of boosting assumptions proposed in the literature, showing that different boosting mechanisms lead to very different stationary distributions of the immunity at the endemic steady state. In the situation of periodic disease outbreaks, the waveforms of immunity distributions are studied and visualized. Our results show that there is a possibility to infer the boosting mechanism from the population level immune dynamics.

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Super-Fine Structure in the Critical Flow-Rate of Critical Flow Venturi Nozzles

Volume 1: Fora, Parts A and B ◽

10.1115/fedsm2002-31079 ◽

2002 ◽

Cited By ~ 3

Author(s):

Masahiro Ishibashi

Keyword(s):

Fine Structure ◽

Steady State ◽

Discharge Coefficient ◽

Constant Pressure ◽

Pressure Ratio ◽

Critical Flow ◽

Time Intervals ◽

Critical Flow Rate ◽

A Value ◽

Long Time

It is shown that critical flow Venturi nozzles need time intervals, i.e., more than five hours, to achieve steady state conditions. During these intervals, the discharge coefficient varies gradually to reach a value inherent to the pressure ratio applied. When a nozzle is suddenly put in the critical condition, its discharge coefficient is trapped at a certain value then afterwards approaches gradually to the inherent value. Primary calibrations are considered to have measured the trapped discharge coefficient, whereas nozzles in applications, where a constant pressure ratio is applied for a long time, have a discharge coefficient inherent to the pressure ratio; inherent and trapped coefficients can differ by 0.03–0.04%.

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