scholarly journals Thermokinetic Modelling of High-Temperature Evolution of Primary Nb(C,N) in Austenite Applied to Recrystallization of 316Nb Austenitic Stainless Steel

Metals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 715
Author(s):  
Nicolas Cliche ◽  
Sylvain Ringeval ◽  
Philippe Petit ◽  
Jacques Bellus ◽  
Eric Georges ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Heat Treatments ◽  
Recrystallization Behavior ◽  
Bearing Steels ◽  
Size Evolution ◽  
Nb Content ◽  
Change In The Mean ◽  
The Mean ◽  
Hot Torsion ◽  
First Time

The size evolution of niobium carbonitrides Nb(C,N) and the evolution of the composition of an austenitic matrix in 316Nb stainless steel were simulated using DICTRA software. For the first time, the complete nine-element composition of steel was taken into account during isothermal and even anisothermal heat treatments. A reduced model was then proposed to optimize the calculation time for complex heat treatments. The change in the mean Nb content in austenite due to Nb(C,N) evolution during different heat treatments was studied. It qualitatively agrees with experimental data as obtained by electron probe microanalysis. Furthermore, the model was successfully applied to explain the effect of heat treatments on the recrystallization behavior of 316Nb steel during hot torsion tests. Moreover, the effect of the thermodynamic database and the number of alloying elements chosen was discussed. We showed that taking into account seven or even nine elements greatly improves the accuracy compared to usual simplified compositions. The proposed method can be useful in designing heat treatments promoting or conversely hindering recrystallization for a wide variety of Nb-bearing steels.

Isotope shifts and hyperfine structure in the atomic spectrum of palladium

1976 ◽  
Vol 351 (1665) ◽  
pp. 267-275 ◽  
Keyword(s):  
High Resolution ◽  
Hyperfine Structure ◽  
Nuclear Charge ◽  
Digital Recording ◽  
Mean Square ◽  
Atomic Spectrum ◽  
Nuclear Charge Distribution ◽  
Change In The Mean ◽  
The Mean ◽  
First Time

The lines λ340.5 nm, λ357.1 nm, and λ677.4 nm of the arc spectrum of palladium have been studied under high resolution by means of digital recording interferometry. The even-even shifts are claimed to be more accurate than previously published work; the relative shifts determined in λ357.1 nm are 102 Pd - 104 Pd, 1.03(2); 104 Pd - 106 Pd, 1.00; 106 Pd - 108 Pd, 1.02(1); 108 Pd - 110 Pd, 0.92(2); 104 Pd - 105 Pd, 0.23(1). An odd-even shift has been measured for the first time in this element, and shows appreciable staggering. The relative shift 102 Pd - 104 Pd has been found to be substantially greater than the values reported in the literature. Values of the change in the mean square radius of the nuclear charge distribution have been deduced from the measurements, all to an accuracy of Ŧ15% ; these are: 102 Pd - 104 Pd, 0.176 fm 2 ; 104 Pd - 106 Pd, 0.170 fm 2 ; 106 Pd - 108 Pd, 0.173 fm 2 ; 108 Pd - 110 Pd, 0.153 fm 2 .

RESULTS OF INTRALESIONAL TRIAMCINOLONE ACETONIDE FOR CHALAZION TREATMENT

2011 ◽  
pp. 100-104
Author(s):  
Thi Thu Nguyen ◽  
Viet Hien Vo ◽  
Thi Em Do
Keyword(s):  
Success Rate ◽  
Key Words ◽  
Triamcinolone Acetonide ◽  
Lower Eyelid ◽  
Upper Eyelid ◽  
Interventional Trial ◽  
The Mean ◽  
First Time

The study use intralesional triamcinolone acetonide injection proceduce for chalazion treatment.1. Objectives: To evaluate results of intralesional triamcinolone acetonide injection for chalazion treatment. 2. Method: This noncomparative prospective interventional trial included 72 chalazions of 61 patients. 3. Results: 61 patients (72 chalazions) with 19 males (31.1%) và 42 females (68.9%), the mean age was 24 ± 9,78 years. 31.1% patients was the first time chalazion and 68.9% patients was more than one times chalazion including 78.6% patients was recurrent at the first position and 21.4% patients occur at new position. 72 chalazions with 16 (22.2%) chalazions was treated before and 56 (77.8%) chalazions wasn’t done that. 72 chalazions with 49 chalazions (68.1%) are local in upper eyelid and 23 chalazions (31.9%) are local in lower eyelid. The mean of chalazion diameter is 6.99 ± 3.03mm. Intralesional triamcinolone acetonide is injected to treat 72 chalazions with 16 (22.2%) chalazions are injected through the route of skin and 56 (77.8%) chalazions are injected through the route of conjunctiva. After 2 weeks follow-up, the success rate was 93.1% and 6.9% failed. 4. Conclusion: intralesional triamcinolone acetonide injection for chalazion treatment is really effective. Key words: chalazion, intralesional triamcinolone acetonide.

Synthesis of a silymarin-gold nanoparticle conjugate and analysis of its liver-protecting activity

2021 ◽  
Vol 22 ◽  
Author(s):  
Sergey Staroverov ◽  
Sergey Kozlov ◽  
Alexander Fomin ◽  
Konstantib Gabalov ◽  
Alexey Volkov ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Liver Disease ◽  
Carbon Tetrachloride ◽  
Glutathione Depletion ◽  
Laboratory Animals ◽  
Experimental Hepatitis ◽  
Acute Liver Disease ◽  
The Mean ◽  
Extent Of Damage ◽  
First Time

Background: The liver disease problem prompts investigators to search for new methods of liver treatment. Introduction: Silymarin (Sil) protects the liver by reducing the concentration of free radicals and the extent of damage to the cell membranes. A particularly interesting method to increase the bioavailability of Sil is to use synthesized gold nanoparticles (AuNPs) as reagents. The study considered whether it was possible to use the silymarin-AuNP conjugate as a potential liver-protecting drug. Method: AuNPs were conjugated to Sil and examine the liver-protecting activity of the conjugate. Experimental hepatitis and hepatocyte cytolysis after carbon tetrachloride actionwere used as a model system, and the experiments were conducted on laboratory animals. Result: For the first time, silymarin was conjugated to colloidal gold nanoparticles (AuNPs). Electron microscopy showed that the resultant preparations were monodisperse and that the mean conjugate diameter was 18–30 nm ± 0.5 nm (mean diameter of the native nanoparticles, 15 ± 0.5 nm). In experimental hepatitis in mice, conjugate administration interfered with glutathione depletion in hepatocytes in response to carbon tetrachloride was conducive to an increase in energy metabolism, and stimulated the monocyte–macrophage function of the liver. The results were confirmed by the high respiratory activity of the hepatocytes in cell culture. Conclusion: We conclude that the silymarin-AuNP conjugate holds promise as a liver-protecting agent in acute liver disease caused by carbon tetrachloride poisoning.

scholarly journals Neutrosophic ratio-type estimators for estimating the population mean

2021 ◽  
Author(s):  
Zaigham Tahir ◽  
Hina Khan ◽  
Muhammad Aslam ◽  
Javid Shabbir ◽  
Yasar Mahmood ◽  
...  
Keyword(s):  
Minimum Mean Square Error ◽  
Auxiliary Information ◽  
Population Parameter ◽  
Uncertain Information ◽  
Population Mean ◽  
Classical Statistics ◽  
Neutrosophic Statistics ◽  
The Mean ◽  
Type Data ◽  
First Time

AbstractAll researches, under classical statistics, are based on determinate, crisp data to estimate the mean of the population when auxiliary information is available. Such estimates often are biased. The goal is to find the best estimates for the unknown value of the population mean with minimum mean square error (MSE). The neutrosophic statistics, generalization of classical statistics tackles vague, indeterminate, uncertain information. Thus, for the first time under neutrosophic statistics, to overcome the issues of estimation of the population mean of neutrosophic data, we have developed the neutrosophic ratio-type estimators for estimating the mean of the finite population utilizing auxiliary information. The neutrosophic observation is of the form $${Z}_{N}={Z}_{L}+{Z}_{U}{I}_{N}\, {\rm where}\, {I}_{N}\in \left[{I}_{L}, {I}_{U}\right], {Z}_{N}\in [{Z}_{l}, {Z}_{u}]$$ Z N = Z L + Z U I N where I N ∈ I L , I U , Z N ∈ [ Z l , Z u ] . The proposed estimators are very helpful to compute results when dealing with ambiguous, vague, and neutrosophic-type data. The results of these estimators are not single-valued but provide an interval form in which our population parameter may have more chance to lie. It increases the efficiency of the estimators, since we have an estimated interval that contains the unknown value of the population mean provided a minimum MSE. The efficiency of the proposed neutrosophic ratio-type estimators is also discussed using neutrosophic data of temperature and also by using simulation. A comparison is also conducted to illustrate the usefulness of Neutrosophic Ratio-type estimators over the classical estimators.

scholarly journals P1398 Echocardiographic continuous monitoring of exercise stress test using probe fixation device

2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
K Wdowiak-Okrojek ◽  
P Wejner-Mik ◽  
Z Bednarkiewicz ◽  
P Lipiec ◽  
J D Kasprzak
Keyword(s):  
Image Quality ◽  
Physical Exercise ◽  
Stress Test ◽  
Exercise Stress Test ◽  
Bicycle Ergometer ◽  
Exercise Stress ◽  
Fixation Device ◽  
The Mean ◽  
First Time

Abstract Background Stress echocardiography (SE) plays an important role among methods of noninvasive diagnosis of ischemic disease. Despite the advantages of physical exercise as the most physiologic stressor, it is difficult (bicycle ergometer) or impossible (treadmill) to obtain and maintain the acoustic window during the exercise. Recently, an innovative probe fixation device was introduced and a research plan was developed to assess the feasibility of external probe fixation during exercise echocardiography on a supine bicycle and upright treadmill exercise for the first time. Methods 37 subjects (36 men, mean age 39 ± 16 years, 21 healthy volunteers, 16 patients with suspected coronary artery disease) were included in this study. This preliminary testing stage included mostly men due to more problematic probe fixation in women. All subjects underwent a submaximal exercise stress test on a treadmill (17/37) or bicycle ergometer (11/37). Both sector and matrix probes were used. We assessed semi-quantitatively the quality of acquired apical views at each stage – the four-point grading system was used (0-no view, 1-suboptimal quality, 2-optimal quality, 3-very good quality), 2-3 sufficient for diagnosis. Results The mean time required for careful positioning of the probe and image optimization was 12 ± 3 min and shortened from 13,7 to 11,1 minutes (mean) in first vs second half of the cohort documenting learning curve. At baseline, 9 patients had at least one apical view of quality precluding reliable analysis. Those patients were excluded from further assessment. During stress, 17 patients maintained the optimal or very good quality of all apical views, whereas in 11 patients the quality significantly decreased during the stress test and required probe repositioning. The mean image quality score at baseline was 2,61 ± 0,48 and 2,25 ± 0,6 after exercise. Expectedly, good image quality was easier to obtain and maintain in the supine position (score 2,74 ± 0,44) points as compared with upright position (score 2,25 ± 0,57). Conclusion This preliminary, unique experience with external probe fixation device indicates that continuous acquisition and monitoring of echocardiographic images is feasible during physical exercise, and for the first time ever - also on the treadmill. This feasibility data stem from almost exclusively male patients and the estimated rate of sufficient image quality throughout the entire test is currently around 60%. We are hoping, that gaining more experience with the product could increase the success rate on exercise tests. Abstract P1398 Figure. Treadmill and ergometer stress test

THE INFLUENCE OF WEIGHT AND HEIGHT ON WEIGHT CHANGES ASSOCIATED WITH PREGNANCY IN WOMEN

1957 ◽  
Vol 15 (4) ◽  
pp. 423-429 ◽  
Author(s):  
THOMAS McKEOWN ◽  
R. G. RECORD
Keyword(s):  
Weight Change ◽  
Weight Changes ◽  
Body Build ◽  
Weight Increment ◽  
Time Table ◽  
The Mean ◽  
Significant Change ◽  
First Time

SUMMARY Three hundred and eighty-three women whose weights were recorded during and after pregnancy were divided into groups of short (under 64 in.) and tall (64 in. and over) individuals, and further subdivided according to an index of body build (based on the observed regression of antenatal weight on height). Differences between the weight 12 months after delivery and the antenatal weight (adjusted according to the number of days by which it preceded or followed the 124th day of gestation) were examined. The proportion of short women who added weight in this interval was relatively high for those who were thinnest at the antenatal examination, was lowest for those who were moderately thin and thereafter increased with increasing degree of obesity (from about 1 in 3 to 4 in 5); the proportion of tall women who added weight showed no significant change (Fig. 2). This variation in weight change according to height is exhibited by women pregnant for the first time (Table 3). For both short and tall women, the mean weight increment of those who added weight, and the mean weight decrement of those who lost weight, increased with increasing degree of obesity (Fig. 3). When weight change is expressed as a proportion of the antenatal weight these trends disappear (Fig. 4).

scholarly journals Modeling of temporal groundwater level variations based on a Kalman filter adaptation algorithm with exogenous inputs

2016 ◽  
Vol 19 (2) ◽  
pp. 191-206 ◽  
Author(s):  
Emmanouil A. Varouchakis
Keyword(s):  
Kalman Filter ◽  
Groundwater Level ◽  
Auxiliary Information ◽  
Model Parameters ◽  
Adaptation Algorithm ◽  
Arx Model ◽  
Resources Management ◽  
Temporal Modelling ◽  
The Mean ◽  
First Time

Reliable temporal modelling of groundwater level is significant for efficient water resources management in hydrological basins and for the prevention of possible desertification effects. In this work we propose a stochastic method of temporal monitoring and prediction that can incorporate auxiliary information. More specifically, we model the temporal (mean annual and biannual) variation of groundwater level by means of a discrete time autoregressive exogenous variable (ARX) model. The ARX model parameters and its predictions are estimated by means of the Kalman filter adaptation algorithm (KFAA) which, to our knowledge, is applied for the first time in hydrology. KFAA is suitable for sparsely monitored basins that do not allow for an independent estimation of the ARX model parameters. We apply KFAA to time series of groundwater level values from the Mires basin in the island of Crete. In addition to precipitation measurements, we use pumping data as exogenous variables. We calibrate the ARX model based on the groundwater level for the years 1981 to 2006 and use it to predict the mean annual and biannual groundwater level for recent years (2007–2010). The predictions are validated with the available annual averages reported by the local authorities.

Seven years follow-up of corneal cross-linking (CXL) in pediatric patients: Evaluation of treated and untreated eye

2021 ◽  
pp. 112067212110206
Author(s):  
Iliya Simantov ◽  
Lior Or ◽  
Inbal Gazit ◽  
Biana Dubinsky-Pertzov ◽  
David Zadok ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Pediatric Patients ◽  
Pediatric Population ◽  
Corneal Thickness ◽  
Cross Linking ◽  
Uncorrected Distance Visual Acuity ◽  
Mild Reduction ◽  
Change In The Mean ◽  
The Mean

Background: Retrospective cohort study evaluating long term keratoconus progression amongst cross-linking (CXL) treated pediatric patients in the treated and the fellow untreated eyes. Methods: Data on 60 eyes of 30 patients, 18 years old or younger, who underwent CXL in at least one eye was collected and analyzed. Follow-up measurements taken from the treated and untreated eye up to 7 years after CXL treatment, were compared to baseline measurements. Parameters included uncorrected distance visual acuity (UCDVA), best-corrected spectacle visual acuity (BCSVA), manifest refraction, pachymetry, corneal tomography, and topography. Results: Mean age of patients was 16 ± 2.1 years. For the treated eyes, during follow-up period mean UCDVA had improved (from 0.78 ± 0.22 at baseline to 0.58 ± 0.26 logMAR at 7 years; p = 0.13), as well as mean BCSVA (from 0.23 ± 0.107 at baseline to 0.172 ± 0.05 logMAR at 7 years; p = 0.37). The mean average keratometry showed a significant flattening (from 49.95 ± 4.04 to 47.94 ± 3.3 diopters (D); p < 0.001), However there was no change in the mean maximal keratometry. The mean minimal corneal thickness (MCT) showed a significant mild reduction of 26 µm ( p = 0.006). Although statistically insignificant, the mean manifest cylinder was also reduced to 2D ( p = 0.15). During the follow-up period, eight untreated eyes (26.6%) deteriorated and underwent CXL, while only one treated eye (3.33%) required an additional CXL. Conclusion: CXL is a safe and efficient procedure in halting keratoconus progression in the pediatric population, the fellow eye needs to be carefully monitored but only a 25% of the patients will require CXL in that eye during a period of 7 years.

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