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1.
Phys Rev Lett ; 127(15): 151301, 2021 Oct 08.
Article in English | MEDLINE | ID: mdl-34678017

ABSTRACT

We present results from an analysis of all data taken by the BICEP2, Keck Array, and BICEP3 CMB polarization experiments up to and including the 2018 observing season. We add additional Keck Array observations at 220 GHz and BICEP3 observations at 95 GHz to the previous 95/150/220 GHz dataset. The Q/U maps now reach depths of 2.8, 2.8, and 8.8 µK_{CMB} arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈600 square degrees at 95 GHz and ≈400 square degrees at 150 and 220 GHz. The 220 GHz maps now achieve a signal-to-noise ratio on polarized dust emission exceeding that of Planck at 353 GHz. We take auto- and cross-spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz and evaluate the joint likelihood of the spectra versus a multicomponent model of lensed ΛCDM+r+dust+synchrotron+noise. The foreground model has seven parameters, and no longer requires a prior on the frequency spectral index of the dust emission taken from measurements on other regions of the sky. This model is an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r_{0.05}<0.036 at 95% confidence. Running maximum likelihood search on simulations we obtain unbiased results and find that σ(r)=0.009. These are the strongest constraints to date on primordial gravitational waves.

2.
Phys Rev Lett ; 121(22): 221301, 2018 Nov 30.
Article in English | MEDLINE | ID: mdl-30547645

ABSTRACT

We present results from an analysis of all data taken by the bicep2/Keck CMB polarization experiments up to and including the 2015 observing season. This includes the first Keck Array observations at 220 GHz and additional observations at 95 and 150 GHz. The Q and U maps reach depths of 5.2, 2.9, and 26 µK_{CMB} arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈400 square degrees. The 220 GHz maps achieve a signal to noise on polarized dust emission approximately equal to that of Planck at 353 GHz. We take auto and cross spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz. We evaluate the joint likelihood of the spectra versus a multicomponent model of lensed-ΛCDM+r+dust+synchrotron+noise. The foreground model has seven parameters, and we impose priors on some of these using external information from Planck and WMAP derived from larger regions of sky. The model is shown to be an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r_{0.05}<0.07 at 95% confidence, which tightens to r_{0.05}<0.06 in conjunction with Planck temperature measurements and other data. The lensing signal is detected at 8.8σ significance. Running a maximum likelihood search on simulations we obtain unbiased results and find that σ(r)=0.020. These are the strongest constraints to date on primordial gravitational waves.

3.
Phys Rev Lett ; 116(3): 031302, 2016 Jan 22.
Article in English | MEDLINE | ID: mdl-26849583

ABSTRACT

We present results from an analysis of all data taken by the BICEP2 and Keck Array cosmic microwave background (CMB) polarization experiments up to and including the 2014 observing season. This includes the first Keck Array observations at 95 GHz. The maps reach a depth of 50 nK deg in Stokes Q and U in the 150 GHz band and 127 nK deg in the 95 GHz band. We take auto- and cross-spectra between these maps and publicly available maps from WMAP and Planck at frequencies from 23 to 353 GHz. An excess over lensed ΛCDM is detected at modest significance in the 95×150 BB spectrum, and is consistent with the dust contribution expected from our previous work. No significant evidence for synchrotron emission is found in spectra such as 23×95, or for correlation between the dust and synchrotron sky patterns in spectra such as 23×353. We take the likelihood of all the spectra for a multicomponent model including lensed ΛCDM, dust, synchrotron, and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r) using priors on the frequency spectral behaviors of dust and synchrotron emission from previous analyses of WMAP and Planck data in other regions of the sky. This analysis yields an upper limit r_{0.05}<0.09 at 95% confidence, which is robust to variations explored in analysis and priors. Combining these B-mode results with the (more model-dependent) constraints from Planck analysis of CMB temperature plus baryon acoustic oscillations and other data yields a combined limit r_{0.05}<0.07 at 95% confidence. These are the strongest constraints to date on inflationary gravitational waves.

4.
Wiad Lek ; 53(7-8): 469-74, 2000.
Article in Polish | MEDLINE | ID: mdl-11070773

ABSTRACT

The new standards of cardiopulmonary resuscitation (CPR), being the result of the World Health Organisation and the European Resuscitation Council studies, should be introduced to the hospital practice everywhere. The aim of this study is to create the project of organisation of the effective CPR system in the big, multidisciplinary hospital--Central Teaching Hospital of the Silesian University of Medicine in Katowice. We propose to establish the interdisciplinary Hospital Resuscitation Council (HRC) consisted of competent representatives of doctors and nurses from all departments with the head of department of anaesthesiology and intensive therapy as a leader of this group. The HRC will be responsible for introducing the effective teaching program of cardiac arrest assessment and basic life support for the whole hospital staff including physicians, nurses, nursing students and lay people. Clear rules of CPR-Alarm, call-system and "do not resuscitate" patients should be established and introduced. There is a need of elaboration of the uniform documentation system and continuous analysis of the effects of CPR activity in the hospital. Anticipated costs of this project are high but the safety of our patients and quality of medical service in the hospital will improve significantly.


Subject(s)
Cardiopulmonary Resuscitation/education , Health Personnel/education , Health Services Administration , Patient Care Team , Hospitals , Humans , Poland
5.
J Physiol Pharmacol ; 51(1): 151-9, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10768858

ABSTRACT

The aim of this study was to evaluate a usefulness of thoracic electrical bioimpedance (TEB) in following adaptive haemodynamic adjustments to postural change and isometric exercise. Sixteen subjects with intact cardiovascular system took part in this study. Haemodynamic parameters were obtained in recumbency and after taking up erect posture. Besides, TEB was performed during handgrip test and the results were compared with baseline resting data. Each time the radionuclide ventriculography (RV) was performed concurrently with TEB to obtain an independent measurement of ejection fraction (EF). Active orthostasis was associated with a change in stroke volume, cardiac output and total vascular resistance by -29.7%, -3.4%, +3.9%, respectively. The handgrip produced a significant increase in cardiac output by 16.3%, however it was not associated with an enhancement of stroke volume. Although there was a moderate correlation between EF calculated by TEB and RV in supine position (r=0.66; p < 0.001), TEB failed to reflect changes of EF in orthostasis and isometric exercise. In conclusion, our results suggest that TEB offers in subjects with normal cardiovascular function a valuable alternative to cardiovascular monitoring of stroke volume and cardiac output, but calculation of EF is associated with a risk of serious error.


Subject(s)
Stroke Volume , Thorax/physiology , Electric Impedance , Female , Hand Strength/physiology , Humans , Male , Middle Aged , Posture/physiology , Radionuclide Ventriculography
6.
Boll Chim Farm ; 138(7): 359-63, 1999.
Article in English | MEDLINE | ID: mdl-10597657

ABSTRACT

An anorectic drug, dexfenfluramine (dF) is commonly used in obesity treatment. The aim of our study was to investigate if dexfenfluramine used alone or together with alpha 2-adrenolitic yohimbine (Y), can change cardiovascular state in obese women.


Subject(s)
Adrenergic alpha-Antagonists/adverse effects , Appetite Depressants/adverse effects , Dexfenfluramine/adverse effects , Hemodynamics/drug effects , Obesity/physiopathology , Yohimbine/adverse effects , Adrenergic alpha-Antagonists/therapeutic use , Adult , Appetite Depressants/therapeutic use , Dexfenfluramine/therapeutic use , Electric Impedance , Exercise Test , Female , Humans , Obesity/drug therapy , Yohimbine/therapeutic use
7.
Clin Physiol ; 18(1): 69-76, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9545623

ABSTRACT

Low caloric diet is a commonly accepted treatment in obesity. However, owing to moderate results, a pharmacological support has been proposed. As some efficacious drugs activate overall sympathetic activity, they might modify functions of the cardiovascular system. Three groups of subjects were studied: (1) nine obese women receiving only a standard hypocaloric diet; (2) nine obese women receiving a standard hypocaloric diet and ephedrine (2 x 25 mg) with caffeine (2 x 200 mg); (3) nine obese women receiving a standard hypocaloric diet and ephedrine (2 x 25 mg) with caffeine (2 x 200 mg) and yohimbine (2 x 5 mg). The cardiovascular state was evaluated by thoracic electrical bioimpedance, automatic sphygmomanometry and continuous ECG recording. In each patient, the haemodynamic study was performed twice: at rest, i.e. before treatment; and after 10 days of treatment. On the same days in each patient, the haemodynamic tests were performed during physical exercises (handgrip stress and cycloergometer exercise). Caffeine and ephedrine had no haemodynamic effect in resting patients. These two drugs led to an increase in ejection fraction during cycloergometer exercise. Addition of yohimbine increased diastolic pressure and heart rate but decreased ejection fraction and stroke index during rest. We also observed that addition of yohimbine decreased ejection fraction during the handgrip and cycloergometer exercise and increased cardiac load during dynamic exercise. Pharmacological supplement of ephedrine and caffeine to a low caloric diet modified the cardiovascular system weakly, but the addition of yohimbine to this regimen attenuated cardiac performance during rest and handgrip and increased cardiac work during dynamic exercise.


Subject(s)
Adrenergic alpha-Antagonists/pharmacology , Appetite Depressants/pharmacology , Caffeine/pharmacology , Cardiography, Impedance , Central Nervous System Stimulants/pharmacology , Ephedrine/pharmacology , Hemodynamics/drug effects , Obesity/physiopathology , Yohimbine/pharmacology , Adult , Body Mass Index , Diet, Reducing , Exercise Test , Female , Hemodynamics/physiology , Humans , Obesity/diet therapy , Obesity/drug therapy
8.
Liver ; 17(1): 1-6, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9062872

ABSTRACT

It seems that hypervolemia and vasodilatation coincide in compensated cirrhosis, but neither rank nor importance of these factors has been fully clarified in adaptive response to postural change. We studied, with gated equilibrium radionuclide angiography and thoracic electrical bioimpedance the hemodynamic status of 19 patients with compensated cirrhosis and 18 healthy subjects in upright and supine positions. In the upright position, the cirrhotic patients were hypotensive and had decreased peripheral vascular resistance despite increased cardiac output. The transition to the supine position was accompanied by a significant fall in the heart rate and an increase in the stroke volume in both controls (92 +/- 22 to 63 +/- 10 beats/min, and 38 +/- 9 to 62 +/- 19 ml/m2, respectively) and cirrhotic patients (101 +/- 20 to 79 +/- 13 beats/min, and 44 +/- 15 to 63 +/- 19 ml/m2, respectively). Besides, the diastolic arterial pressure fell in controls from 89 +/- 9 mmHg to 81 +/- 11 mmHg; p < 0.01, while it remained unchanged in cirrhotic patients (77 +/- 17 vs 82 +/- 13 mmHg). In the supine position, the cirrhotic patients presented tachycardia and left ventricular hyperkinesy (increased velocity of left ventricular filling and emptying). In conclusion, these results show that in compensated cirrhosis the decreased arterial tone and peripheral blood pooling are important factors of adaptive hemodynamic reaction to postural change.


Subject(s)
Hemodynamics , Liver Cirrhosis/physiopathology , Posture/physiology , Adult , Blood Pressure , Cardiac Output/physiology , Cardiography, Impedance , Female , Gated Blood-Pool Imaging , Heart Rate/physiology , Humans , Male , Middle Aged
9.
Biull Eksp Biol Med ; 107(6): 658-60, 1989 Jun.
Article in Russian | MEDLINE | ID: mdl-2790156

ABSTRACT

The paper studies electrical activity of the heart during the anti-ischemic protection by cool high-potassium cardioplegic solution based on the blood. Parametres characterising automatism function and the myocardial state of the ventricles practically did not differ from the control data obtained during the experiments without ischemia. Atrioventricular conduction and the atrium myocardium were worse preserved. The positive effects of the papaverine addition to the cardioplegic perfusate has been also shown. The author came to the conclusion that it is necessary to pay special attention to the electrical activity of the supraventricular area of the heart for the adequate evaluation of the cardioplegia.


Subject(s)
Coronary Disease/prevention & control , Heart/physiopathology , Animals , Atropine/pharmacology , Coronary Disease/physiopathology , Dogs , Droperidol/pharmacology , Electrocardiography , Electrophysiology , Heart/drug effects , Heart Arrest, Induced/methods , In Vitro Techniques , Papaverine/pharmacology , Perfusion/methods , Promedol/pharmacology , Time Factors
12.
Kardiologiia ; 22(6): 54-8, 1982.
Article in Russian | MEDLINE | ID: mdl-6750204

ABSTRACT

In 12 experiments on dogs heterotopic cardiac allotransplantation on the recipient's neck has been performed. During the transplant survival its electrical activity and the coronary blood flow (CBF) were recorded with an implanted sensor of electromagnetic flowmeter. The combination of relatively low CBF and the amplitude of R wave during the first hours after transplantation with a high heart rate is a poor prognostic sign. Oscillations of CBF run parallel to changes of ECG when the viability of the transplant is retained, during the rejection crisis these changes do not correlate. The significance of comprehensive assessment of the cardiac function with the use of ECG and CBF measurement and comparison of their absolute figures and dynamics is shown to be of importance for the early diagnosis of the rejection crisis.


Subject(s)
Coronary Circulation , Graft Rejection , Heart/physiology , Animals , Dogs , Electrocardiography , Female , Heart Rate , Heart Transplantation , Male , Time Factors , Transplantation, Homologous
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