40Ar–39Ar incremental heating study of mineral separates from the early Archean east Indian craton: implications for the thermal history of a section of the Singbhum Granite batholithic complex

1987 ◽  
Vol 24 (10) ◽  
pp. 1985-1993 ◽  
Author(s):  
Ajoy K. Baksi ◽  
D. A. Archibald ◽  
S. N. Sarkar ◽  
A. K. Saha
Keyword(s):  
High Precision ◽  
Thermal History ◽  
Eastern India ◽  
Slow Cooling ◽  
East Indian ◽  
History Of ◽  
Tonalitic Gneiss ◽  
Indian Craton ◽  
Very High

40Ar–39Ar incremental heating studies on mineral separates from three sets of rocks in the Singbhum craton in eastern India have helped unravel the thermochronometric history of the terrane and explain an earlier discrepancy between Sm–Nd (~3800 Ma) and Rb–Sr (~3100 Ma) whole-rock ages for the Older Metamorphic Tonalitic Gneiss (OMTG). High precision plateau ages for hornblende separates from the Older Metamorphic Group of rocks (OMG) suggest that this unit is older than 3300 Ma and that enclaves of both the OMTG and OMG within the batholithic complex cooled to ~500 °C at 3300 ± 15 Ma following engulfment in magma, forming the Singbhum Granite (SG). Results from a biotite separate from the OMTG imply that slow cooling continued to a temperature of ~300 °C at ~3160 Ma. Study of a feldspar separate from the Singbhum Granite, suggests final cooling (uplift?) through the ~150 °C isotherm ~660 Ma ago.We suggest that an earlier Rb–Sr whole-rock age of 3130 ± 85 Ma on the OMTG did not yield the crystallisation age, but rather the time of cooling to strontium retention temperature for the biotite in these rocks. We also demonstrate that for hornblende and mica from Archean rocks, 40Ar–39Ar incremental heating experiments can yield very high precision plateau ages (e.g., ± 2 to ± 5 Ma at 3300 Ma). In practice, however, we suggest this technique can separate events in the early Archean spaced ~30 Ma apart.

Phase Stability in Binary Ti-Al

1990 ◽  
Vol 186 ◽  
Author(s):  
C.D. Anderson ◽  
W.H. Hofmeister ◽  
R.J. Bayuzick
Keyword(s):  
Phase Diagram ◽  
Thermal History ◽  
Sampling Rate ◽  
Electromagnetic Levitation ◽  
Solidification Structure ◽  
High Undercooling ◽  
The Third ◽  
High Sampling Rate ◽  
History Of ◽  
Very High

AbstractBinary Ti-Al samples containing from 46 to 54 at.% Al were solidified while undercooled by various amounts using electromagnetic levitation techniques. A detailed thermal history of these samples was obtained with sampling rates as high as 500 KHz during recalescence. This very high sampling rate was essential to resolve the thermal events. Primary α solidification was observed in samples containing from 51 to 54 at.% Al that were undercooled less than about 100 K at solidification. Primary β solidification was found for all undercoolings tested in samples containing less than 51 at.% Al and for undercoolings greater than about 100 K in samples containing 51 to 54 at.% Al. These first two observations are in agreement with results from Valencia et al. for Ti-45 at.% Al and Ti-50 at.% Al, respectively [4]. However, the third observation of β as the primary solidification structure at high undercooling and 54 at.% Al differs from Valencia's interpretation for Ti-55 at.% Al. The results in this study are consistent with the proposed McCullough Ti-Al phase diagram.

Thermal history of the Slušovice-1 borehole

2015 ◽  
Author(s):  
Petr Jirman ◽  
Marek Goldbach ◽  
Eva Geršlová
Keyword(s):  
Thermal History ◽  
History Of

Effect of thermal history of aqueous solutions of KCl on the metastable zone width

1984 ◽  
Vol 49 (3) ◽  
pp. 559-569 ◽  
Author(s):  
Jaroslav Nývlt
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Thermal History ◽  
Equilibrium Solubility ◽  
Metastable Zone Width ◽  
Zone Width ◽  
Preceding Experiment ◽  
History Of ◽  
Metastable Zone ◽  
The Given

The metastable zone width of an aqueous solution of KCI was measured as a function of the time and temperature of overheating above the equilibrium solubility temperature. It has been found that when the experiments follow close upon one another, the parameters of the preceding experiment affect the results of the experiment to follow.The results are interpreted in terms of hypotheses advanced in the literature to account for the effect of thermal history of solution. The plausibility and applicability of these hypotheses are assessed for the given cause of aqueous solution of a well soluble electrolyte.

scholarly journals Antihypertensive Efficacy of Fixed Combination of Amlodipine and Ramipril in Patients with Arterial Hypertension and Very High Cardiovascular Risk

2019 ◽  
Vol 14 (6) ◽  
pp. 840-845
Author(s):  
O. Yu. Korennova ◽  
S. P. Podolnaya ◽  
E. P. Prihodko ◽  
E. A. Turusheva ◽  
S. N. Starinskaya ◽  
...  
Keyword(s):  
Cardiovascular Risk ◽  
Coronary Artery ◽  
Fixed Combination ◽  
Antihypertensive Drugs ◽  
Antihypertensive Efficacy ◽  
High Cardiovascular Risk ◽  
Hypertensive Patients ◽  
Coronary Artery Stenting ◽  
History Of ◽  
Very High

Aim. To evaluate the antihypertensive efficacy and tolerability of a fixed combination of amlodipine and ramipril in hypertensive patients with very high cardiovascular risk. Material and methods. A retrospective cohort study of real clinical practice of prescribing antihypertensive drugs according to 255 medical records of outpatient hypertensive patients with a history of acute coronary syndrome (ACS) and coronary artery stenting was performed in the first part. An open observational study was performed in the second part. 69 people older than 18 years with a history of ACS and coronary artery stenting, without reaching the target blood pressure (BP) level while using free combinations of antihypertensive drugs and with indications for a fixed combination of ramipril and amlodipine were included into the study. Analysis of self-monitoring of BP, office BP, daily BP monitoring (ABPM) and patients’ adherence to treatment (Morisky-Green test) initially, after 4 and after 12 weeks of taking the fixed combination of ramipril and amlodipine was performed to assess the clinical efficacy of the studied drug. Results. It was found that 42.0% of patients did not follow the recommendations for regular intake of antihypertensive drugs. So, hypertension of all patients regarded as false-refractory, which was the basis for the prescription of the fixed combination of ramipril and amlodipine in accordance with clinical guidelines for the diagnosis and treatment of hypertension. After 4 weeks of therapy, there was significant decrease in office BP with the achievement and preservation of the target level by the 12th week, normalization to the 12th week of day and night BP variability in 54.9% of patients. 78.0% of patients followed medical recommendations for regular administration of antihypertensive drugs, none of the patients had adverse events. Conclusion. The use of fixed combinations of drugs, in particular, amlodipine and ramipril as a part of multicomponent therapy in hypertensive patients with very high cardiovascular risk, led to the achievement of target BP by the 4th week of therapy and stable preservation of antihypertensive effect in 12 weeks of treatment as well as gradual normalization of day and night BP variability in more than half of patients. Fixed combination of ramipril and amlodipine allowed to improve adherence of patients to cardiovascular diseases.

scholarly journals Separate Universe calibration of the dependence of halo bias on cosmic web anisotropy

2020 ◽  
Vol 499 (3) ◽  
pp. 4418-4431 ◽  
Author(s):  
Sujatha Ramakrishnan ◽  
Aseem Paranjape
Keyword(s):  
Dark Matter ◽  
High Precision ◽  
Gaussian Distribution ◽  
Initial Perturbation ◽  
Analytical Framework ◽  
Web Environment ◽  
Wide Range ◽  
Galaxy Assembly ◽  
Very High ◽  
Good Agreement

ABSTRACT We use the Separate Universe technique to calibrate the dependence of linear and quadratic halo bias b1 and b2 on the local cosmic web environment of dark matter haloes. We do this by measuring the response of halo abundances at fixed mass and cosmic web tidal anisotropy α to an infinite wavelength initial perturbation. We augment our measurements with an analytical framework developed in earlier work that exploits the near-lognormal shape of the distribution of α and results in very high precision calibrations. We present convenient fitting functions for the dependence of b1 and b2 on α over a wide range of halo mass for redshifts 0 ≤ z ≤ 1. Our calibration of b2(α) is the first demonstration to date of the dependence of non-linear bias on the local web environment. Motivated by previous results that showed that α is the primary indicator of halo assembly bias for a number of halo properties beyond halo mass, we then extend our analytical framework to accommodate the dependence of b1 and b2 on any such secondary property that has, or can be monotonically transformed to have, a Gaussian distribution. We demonstrate this technique for the specific case of halo concentration, finding good agreement with previous results. Our calibrations will be useful for a variety of halo model analyses focusing on galaxy assembly bias, as well as analytical forecasts of the potential for using α as a segregating variable in multitracer analyses.

The Thermal History of the Earth

Nature ◽  
1956 ◽  
Vol 177 (4500) ◽  
pp. 155-157 ◽  
Author(s):  
J. A. JACOBS ◽  
D. W. ALLAN
Keyword(s):  
Thermal History ◽  
The Earth ◽  
History Of

scholarly journals AB0420 RISK OF DEVELOPING TYPE 2 DIABETES MELLITUS IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1510.2-1510
Author(s):  
L. Kondrateva ◽  
T. Popkova ◽  
E. Nasonov ◽  
A. Lila
Keyword(s):  
Abdominal Obesity ◽  
Lupus Erythematosus ◽  
Antihypertensive Drugs ◽  
Control Group ◽  
Systemic Lupus ◽  
Type 2 Dm ◽  
History Of ◽  
Systemic Rheumatic Diseases ◽  
Very High

Background:Patients with systemic lupus erythematosus (SLE) have higher than in general population prevalence of diabetes mellitus (DM). Hyperinsulinemia is a predictor of developing type 2 DM, however routine measurement of insulin levels for DM risk assessment is uncomfortable in daily clinical practice. International Diabetes Federation recommends the use of patient questionnaires to quickly identify people who may be at a higher risk of DM development.Objectives:To determine the 10-years risk of developing type 2 DM in SLE patients using dedicated questionnaire - Finnish Type 2 Diabetes Risk Assessment Form (FINDRISK) data.Methods:The study included 92 SLE patients without DM (83 women, 9 men, 39 [34; 47] years old). The median disease duration was 6 [2,14] years, SLEDAI-2K was 4[2;8]. SLE pts were treated with glucocorticoids (GC) (89%) and hydroxychloroquine (78%), immunosuppressive drugs (28%) and biological agents (10%). The control group consisted of 88 subjects without systemic rheumatic diseases, inflammatory arthritis or DM, matched by age and sex with SLE patients. Eight items of FINDRISK questionnaire (age, overweight, abdominal obesity, family history of diabetes, physical inactivity, eating habits, history of antihypertensive drugs treatment, history of hyperglycemia) were taken into account to calculate the total risk score (TS). The risk of developing DM within following 10 years is regarded as low (1%) or slightly elevated (4%) with TS ≤11 points, as moderate (17%), high (33%) or very high (50%) with TS ≥12 points.Results:The risk of developing DM was low or slightly elevated in 65 (71%) SLE pts and moderate, high or very high in 27 (29%) pts. The difference was significant compared with the control group, in which 76 (86%) subjects had a low or slightly elevated risk and 12 (14%) had a moderate, high or very high risk (p=0,01). The number of risk factors (4[2;5]) and the median TS of SLE pts (9[5;12] points) were higher than values in control subjects (3[2,4] factors and 6[3;9] points, respectively) (p<0,01 for both). DM risk factors profiles were similar in two groups, except for higher prevalence of abdominal obesity (66% vs 41%, p<0,01) and history of antihypertensive drugs treatment (57% vs 17%, p<0,01) in SLE. There were positive correlations between TS and CRP levels (r=0,25, p=0,02), SLICC (r=0,36, p<0,01), HAQ (r=0,29, p<0,01), and negative correlations between TS and SLEDAI-2K (r= -0,32, p<0,01), glomerular filtration rate by CKD-EPI (r=-0,23, p=0,03). Current GC use had no influence on TS values in SLE.Conclusion:Patients with SLE were more likely than individuals without systemic rheumatic diseases to have a moderate, high and very high risk of developing DM, and therefore, required interventions to prevent the metabolic disease. Increased risk of developing DM was associated with most common traditional factors, especially by abdominal obesity and regular use of antihypertensive drugs that can be considered a kind of equivalent to the presence of hypertension. Curtain contribution of inflammation, lupus activity and irreversible damage index can’t be ignored. Clarification of SLE-specific phenomena in DM pathogenesis requires further research.Disclosure of Interests: :None declared

Sign in / Sign up

Export Citation Format

Share Document