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1.
Vnitr Lek ; 57(9): 764-71, 2011 Sep.
Artigo em Tcheco | MEDLINE | ID: mdl-21957772

RESUMO

INTRODUCTION: Favourable effect of exercise training on cardiovascular prognosis in patients with metabolic syndrome have been documented in lot of studies. Less information exist about results of cardiovascular rehabilitation in patients with different forms of coronary heart disease and associated diseases and abnormalities within metabolic syndrome. METHODS: The present article evaluates a benefit of combined, aerobic-resistance training in two groups of patients after percutaneous coronary intervention for acute coronary syndrome: with [group MS(+), n = 42] and without [group MS(-), n = 53] metabolic syndrome. The changes in aerobic capacity (VO2 peak, VO2 peak . kg(-1)), physical performance (W peak, W peak . kg(-1)), blood pressure, BMI and waist circumference after 12 weeks of cardiovascular rehabilitation are evaluated. RESULTS: Significant improvement in aerobic capacity and physical performance were found out both in group MS(+) and MS(-) (p < 0.01, resp. p < 0.001). Decrease of systolic blood pressure was significant in MS(+), whereas in MS(-) together with decrease of diastolic BP in both groups were not significant. The increase in aerobic capacity and physical performance in patients of MS(+) is comparable with those in MS(-); the decrease in systolic BP was more intensive in MS(+) compared to MS(-). The changes in waist circumference and BMI were not significant in both groups. CONCLUSION: The results show, that in patients with high number of risk factors associated with metabolic syndrome was demonstrated at least comparable benefit from cardiovascular rehabilitation compared with those without metabolic syndrome.


Assuntos
Síndrome Coronariana Aguda/reabilitação , Terapia por Exercício , Síndrome Metabólica/reabilitação , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/terapia , Angioplastia Coronária com Balão/reabilitação , Humanos , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade
2.
Scr Med (Brno) ; 83(1): 5-15, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21603087

RESUMO

Countering the trend in specialization, we advocate the trans-disciplinary monitoring of blood pressure and heart rate for signatures of environmental cyclic and other variabilities in space as well as terrestrial weather on the one hand, and for surveillance of personal and societal health on the other hand. New rules (if confirmed novel laws) emerge as we recognize our inheritance from the cosmos of cycles that constitute and characterize life and align them with inheritance from parents. In so doing, we happen to follow the endeavors of Gregor Mendel, who recognized the segregation and independent assortment of what became known as genes. Circadians, rhythms with periods, τ, between 20 and 28 hours, and cycles with frequencies that are higher (ultradian) or lower (infradian) than circadian, are genetically anchored. An accumulating long list of very important but aeolian (nonstationary) infradian cycles, characterizing the incidence patterns of sudden cardiac death, suicide and terrorism, with drastically different τs, constitutes the nonphotic (corpuscular emission from the sun, heliogeomagnetics, ultraviolet flux, gravitation) Cornélissen-series.

3.
Scr Med (Brno) ; 83(1): 16-32, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21566725

RESUMO

Three spectral components with periods of about (~) 0.41, ~0.5 and ~1.0 year had been found with serially independent sampling in human circulating melatonin. The time series consisted of around-the-clock samples collected for 24 hours at 4-hour intervals from different patients over several years. Some of these components had been found to be circadian stage-dependent, the daytime measurements following mostly a circannual variation, whereas a half-year characterized the nighttime samples. The latter were incorporated into a circasemiannual map. The relative brevity of the series prevented a check for the coexistence of all three spectral components, even if each component seemed to have a raison d'être. In time series of transdisciplinary data, a 1.00-year synchronized component is interpreted as representing the seasons. The half-year may qualify the circannual waveform, but it is also a signature of geomagnetics. An ~0.41-year (~5-month) component is the signature of solar flares. It has been called a cis-half-year (cis = on this side of a half-year) and may be detected only intermittently. Charles L. Wolff predicted the existence, among others, of ~0.42- and ~0.56-year components as beat periods of rotations at different solar latitudes.The multiple components characterizing circulating melatonin could also be found in a (to our knowledge unique) data set of a clinically healthy scientist (RBS). Herein, we focus on vascular data self-measured by RBS as he aged from ~20 to ~60 years. A multi-component model consisting of cosine curves with periods of 0.41, 0.50 and 1.00 year was fitted to weekly means of systolic (S) and diastolic (D) blood pressure (BP) and heart rate (HR) collected ~5 times a day over 39 years by RBS. All three components can coexist for a while, although all of them are nonstationary in their characteristics and come and go by the criterion of statistical significance.Intermittently, BP and HR are synchronized selectively with one or the other aspect of RBS' physical environment, namely the seasons (at ~1.0 year), earth magnetism (at ~0.5 year) and/or solar flares (at ~0.42 year). Cosmic-biotic transfer of information, albeit hardly of energy (the biospheric amplitudes are very small) may be mediated in this set of frequency windows. As found earlier, RBS' circulation is also frequency-trapped environmentally in multidecadal windows, HR being locked into the transtridecadal Brückner, or rather Brückner-Egeson-Lockyer, BEL sunspot and terrestrial weather cycle, while his BP follows Hale's didecadal cycle in the changing polarity of sunspots.The ~0.41-year HR cycle may be associated with changes in solar flares, the cis-half-year amplitude of HR showing a cross-correlation coefficient of 0.79 with the total solar flare index (from both solar hemispheres) at a lag of ~3.2 years. The superposed time courses of these two variables indicate the presence of a shared Horrebow-Arago-Schwabe sunspot cycle of ~11 years, the cis-half-year in HR being more prominent after the total solar flare index reaches its ~11-year peak. Differences in the time-varying behavior of BP vs. HR are also described.

4.
5.
Vnitr Lek ; 54(1): 53-61, 2008 Jan.
Artigo em Tcheco | MEDLINE | ID: mdl-18390118

RESUMO

Correctly indicated physical exercise performed and controlled on a regular basis is an inseparable part of treatment and rehabilitation of patients with left ventricular dysfunction. In order to guarantee the best effect and safety of physical exercise, it is necessary to adopt a differential approach to its prescription to patients with different degrees of functional damage. In addition, a number of conditions should be fulfilled, among which, in the first place, the determination of functional classification of patients used in practice and described in the relevant literature (NYHA, AMA, Goldman, Weber). Physical exercise cannot be differentiated only with respect to the degree of dysfunction; other conditioning factors should be taken into consideration, too, among which the relative contraindication of physical strain, somatic condition, physical exercise anamnesis and others (i.e. sex, age, motivation, etc.), causing a high degree of patient heterogeneity. Also described are additional conditions for differentiation and correct application of physical training, which involve the selection of suitable types of exercise and their energetic demands, adequate intensity, frequency and duration; it is also important to determine the available effective and safe methods, programmes and means of training. The article contains examples of the above conditions, as well as classification of physical exercise into functional classes NYHA I-IV. In conclusion, the authors point out the necessity of differentiation of physical training and of cooperation of the cardiologist with the physiotherapist in its indication, implementation and monitoring.


Assuntos
Terapia por Exercício , Disfunção Ventricular Esquerda/reabilitação , Tolerância ao Exercício , Humanos , Disfunção Ventricular Esquerda/classificação , Disfunção Ventricular Esquerda/fisiopatologia
6.
Scr Med (Brno) ; 80(4): 157-166, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19122770

RESUMO

BIOCOS, the project aimed at studying BIOlogical systems in their COSmos, has obtained a great deal of expertise in the fields of blood pressure (BP) and heart rate (HR) monitoring and of marker rhythmometry for the purposes of screening, diagnosis, treatment, and prognosis. Prolonging the monitoring reduces the uncertainty in the estimation of circadian parameters; the current recommendation of BIOCOS requires monitoring for at least 7 days. The BIOCOS approach consists of a parametric and a non-parametric analysis of the data, in which the results from the individual subject are being compared with gender- and age-specified reference values in health.Chronobiological designs can offer important new information regarding the optimization of treatment by timing its administration as a function of circadian and other rhythms.New technological developments are needed to close the loop between the monitoring of blood pressure and the administration of antihypertensive drugs.

7.
Scr Med (Brno) ; 80(4): 151-156, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19129929

RESUMO

The aim of the study was to assess the time structure (chronome) of sudden cardiac death (SCD) in Austria. The daily incidence of SCD (ICD-10 I46.1) in Austria was obtained for the 4-year span from Jan 2002 to Dec 2005. Data were available separately for men and women. This data series was analyzed by linear-nonlinear rhythmometry. The major feature is the detection of a cis-half-year that is validated nonlinearly, the estimated period of the cis-half-year is 0.408 year (95% CI: 0.389, 0.426). It is concluded that the chronobiological analysis of sudden cardiac death in Austria showed the variability of total incidence with the period of a cis-half-year.

8.
Scr Med (Brno) ; 80(4): 175-178, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19424513

RESUMO

Re-evaluation of all functions of baroreflex by means of a simple mathematical model of circulation was the aim of the present study. The following states are modelled: 1. Rest. 2. Immediately after baroreceptor denervation. 3. Several days after denervation. 4. Physical exercise before denervation. 5. Physical exercise several days after denervation. Despite the same cardiac contractility and the same vasodilatation in working muscles as before denervation the cardiac output is by one third lower after baroreceptor denervation. In conclusion, a model simulation revealed the common regulation of blood pressure and blood volume by baroreflex and kidneys as a primary function of baroreflex.

9.
Scr Med (Brno) ; 80(5): 191-196, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19436776

RESUMO

The objective of this study was to find if there was a relationship between the time when cardiovascular rehabilitation was running in the patients after myocardial infarction and an average daily value of systolic and diastolic blood pressure at 7-day ambulatory blood pressure monitoring.Systolic and diastolic pressures significantly increased in patients who underwent cardiovascular rehabilitation in the morning from 9.00 a.m. to 10.15 a.m., and significantly decreased in those who did their physical exercise in the afternoon from 1.30 p.m. to 2.45 p.m., compared to their blood pressure values on days without rehabilitation.

10.
Scr Med (Brno) ; 80(4): 179-188, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19436777

RESUMO

The relationship between age and circadian blood pressure (BP) variation was the aim of the present study. One hundred and eighty-seven subjects (130 males, 57 females), 20-77 years old, were recruited for seven-day BP monitoring. Colin medical instruments (Komaki, Japan) were used for ambulatory BP monitoring (oscillation method, 30-minute interval between measurements). A sinusoidal curve was fitted (minimum square method) and the mean value and amplitude of the curve (double amplitude corresponds to the night-day difference) were evaluated on every day of monitoring. The average 7-day values of the mean (M) and of double amplitude (2A) for systolic BP (SBP), diastolic BP (DBP), and heart rate (HR) were determined in each subject. The mean values of M (+/-SD) for the whole group were: SBP- 127+/-8, DBP - 79+/-6 mmHg, HR - 70+/-6 bpm; of 2A: SBP - 21+/-7, DBP - 15+/-5 mmHg, HR - 15+/-6 bpm. A linear relationship between M of SBP and age (r=0.341, p< 0.001) and DBP and age (r=0.384, p<0.001) was found (difference between 20 and 77 years: SBP - 16, DBP - 12 mmHg). 2A of SBP and DBP was increasing with age up to 35 years, then the curve remained relatively flat up to 55 years (maximum at 45 years), and then it decreased again (difference between 45 and 77 years: SBP - 13mmHg, DBP - 12 mmHg). Heart rate M and 2A were age-independent. The mean values of SBP and DBP were increasing with age up to 75 years, but the night-day difference of SBP and DBP reached its maximum value at 45 years and then decreased.

11.
Scr Med (Brno) ; 80(4): 133-150, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19710947

RESUMO

The mapping of time structures, chronomes, constitutes an endeavor spawned by chronobiology: chronomics. This cartography in time shows signatures on the surface of the earth, cycles, also accumulating in life on the earth's surface. We append a glossary of these and other cycles, the names being coined in the light of approximate cycle length. These findings are transdisciplinary, in view of their broad representation and critical importance in the biosphere. Suggestions of mechanisms are derived from an analytical statistical documentation of characteristics with superposed epochs and superposed cycles and other "remove-and-replace" approaches. These approaches use the spontaneously changing presence or absence of an environmental, cyclic or other factor for the study of any corresponding changes in the biosphere. We illustrate the indispensability of the mapping of rhythm characteristics in broader structures, chronomes, along several or all available different time scales. We present results from a cooperative cartography of about 10, about 20, and about 50-year rhythms in the context of a broad endeavor concerned with the Biosphere and the Cosmos, the BIOCOS project. The participants in this project are our co-authors worldwide, beyond Brno and Minneapolis; the studies of human blood pressure and heart rate around the clock and along the week may provide the evidence for those influences that Mendel sought in meteorology and climatology.

12.
Vnitr Lek ; 52(2): 160-6, 2006 Feb.
Artigo em Tcheco | MEDLINE | ID: mdl-16623279

RESUMO

Head-up tilt table testing is used for diagnostics of vasovagal syncope. Beat-to-beat blood pressure recording and ECG monitoring is not sufficient for clarification of the syncope mechanisms in individual patients, however. That is why a Task Force Monitor was developed in Graz, Austria. In addition this device enables stroke volume recording by impedance method. Other advantages are calculations of cardiac output, beat-to-beat total peripheral resistance, heart rate variability and baroreflex sensitivity as well as activity ofsympathicus and parasympathicus assessment. These methods enable detailed hemodynamic analysis during the whole head-up tilt testing duration, the moment of syncope including.


Assuntos
Hemodinâmica , Monitorização Fisiológica/instrumentação , Síncope Vasovagal/diagnóstico , Teste da Mesa Inclinada , Barorreflexo , Humanos , Síncope Vasovagal/fisiopatologia
13.
Vnitr Lek ; 52(1): 44-50, 2006 Jan.
Artigo em Tcheco | MEDLINE | ID: mdl-16526198

RESUMO

The objective of the study was to evaluate the physiological effectiveness and the influence of two modifications of aerobic training (interval and continuous) on the physical performance in the patients with coronary heart disease. 38 males with coronary heart disease (age 60 +/- 10.2 years) passed three months training programme of 60 min 3 times a week (10 min of warm up phase, 25 min of aerobic phase, 15 min of resistance training, 10 min of relaxing phase). Patients with coronarographically verified stenosis > 50% luminal diameter and/or left ventricular ejection fraction lower than 40 % (n = 22) had in terms of aerobic phase interval training prescribed (30 second work phases with work load intensity on the level of anaerobic threshold alternating with 60 second recovery phases with intensity of 5 W); other patients (n = 16) passed aerobic phase of the programme with continual work load of intensity on the level of ventilatory anaerobic threshold. After the determination of three month rehabilitation programme the maximal achieved performance as well as aerobic capacity evaluated by spiroergometric examination statistically significantly increased in the group of patients with interval training and also in the group with continuous training. Despite the group with interval training performed 2.5-3 times less work in each training unit (p < 0.01), the performance and aerobic capacity parameters after the termination of three month programme did not statistically significantly differ from the group with continuous training. The advantage of the continuous training is a possibility to achieve an improvement also in the patients with left ventricular dysfunction and chronic coronary heart disease who could have worse tolerance of the continual work load.


Assuntos
Terapia por Exercício , Isquemia Miocárdica/reabilitação , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/reabilitação , Isquemia Miocárdica/fisiopatologia , Volume Sistólico
14.
Biomed Pharmacother ; 59 Suppl 1: S152-7, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16275485

RESUMO

Overswinging or CHAT (brief for Circadian Hyper-Amplitude-Tension), that is an excessive circadian variation in blood pressure (BP), has been associated with a large increase in cardiovascular disease risk, present even in the absence of an elevated BP itself. This usually asymptomatic condition is usually overlooked by current practice based on spot-checks, because to be diagnosed, measurements need to be taken around-the-clock, preferably for 7 days at the outset. Once diagnosed, however, a usual circadian BP pattern can be restored by means of certain non-pharmacologic or pharmacologic interventions timed appropriately. Thereby, it is possible to reduce the risk of cardiovascular morbidity and mortality, cerebral ischemic events and nephropathy in particular. For the preparation of guidelines regarding the diagnosis of BP disorders and for the institution of primary as well as secondary preventive measures, it is important to know what the incidence of CHAT is on a global basis. We found 191 cases of CHAT among 1602 mostly 7-day/24-h BP profiles, obtained from several centers in different countries participating in an ongoing project on the BIOsphere and the COSmos (BIOCOS). CHAT incidence is about the same between men and women, but it is diagnosed more often among patients with borderline hypertension or with glucose intolerance. It is also more common among MESOR-hypertensive than among MESOR-normotensive individuals. Priority should be given to the development of an unobtrusive and affordable device to automatically monitor BP and to analyze the data as-one-goes, so that cardiovascular disease risk can be prevented.


Assuntos
Pressão Sanguínea/fisiologia , Ritmo Circadiano/fisiologia , Hipertensão/diagnóstico , Adulto , Feminino , Intolerância à Glucose/complicações , Frequência Cardíaca/fisiologia , Humanos , Hipertensão/epidemiologia , Japão/epidemiologia , Masculino , Medição de Risco , População Rural , Acidente Vascular Cerebral/epidemiologia , População Urbana
15.
Biomed Pharmacother ; 59 Suppl 1: S239-61, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16275502

RESUMO

We analyzed cycles with periods, tau, in the range of 0.8-2.0 years, characterizing, mostly during 1999-2003, the incidence of sudden cardiac death (SCD), according to the International Classification of Diseases, 10th revision (ICD10), code I46.1. In the tau range examined, only yearly components could be documented in time series from North Carolina, USA; Tbilisi, Georgia; and Hong Kong, in the latter two locations based on relatively short time series. By contrast, in Minnesota, USA, we found only a component with a longer than (= trans) yearly (transyearly) tau of 1.39 years; the 95% confidence interval (CI) of the tau extended from 1.17 to 1.61 years, falling into the category of transyears (defined as a tau and a 95% CI between 1.0 and 2.0 years, with the limits of the 95% CI of the spectral component's tau overlapping neither of these lengths). During the same span from 1999 to 2003 in Arkansas, USA, a component of about 1-year in length was present, and in addition, one with a tau of 1.69 year with a CI extending from 1.29 to 2.07 years, a far-transyear candidate, far-transyears being defined as having a tau with a CI between 1.20 and 2.0 year, with the CI overlapping neither of these lengths. In the Czech Republic, there was also a calendar-yearly tau and one of 1.76 years. In the latter two geographic/geomagnetic areas, the about-yearly and the longer cycles' amplitudes were of similar prominence. The taus are only candidate transyears; the 95% CIs of their taus overlap the 2-year length. When a series on SCD from 1994 to 2003 from the Czech Republic was analyzed, the 95% CI of the transyear's tau no longer overlapped the 2-year length. Transyears were also found in the Czech Republic for myocardial infarctions (MI), meeting the original transyear definition in both a shorter and a longer series. Moreover, in the 1994-2003 series on MI from the Czech Republic, a near-transyear was also found, meeting the definition of a period with a 95% CI overlapping neither precisely 1.0 year nor 1.2 years, along with a far-transyear, defined as a tau between 1.2 and 2.0 years, again with the 95% CI covering neither of these lengths. Herein, we discuss near- and far-transyears more generally in the light of their background in physics and the concept of reciprocal cyclicities.


Assuntos
Fenômenos Cronobiológicos , Morte Súbita Cardíaca/epidemiologia , Infarto do Miocárdio/epidemiologia , Atividade Solar , República Tcheca/epidemiologia , Geografia , República da Geórgia/epidemiologia , Hong Kong/epidemiologia , Humanos , Estados Unidos/epidemiologia
16.
Scr Med (Brno) ; 78(2): 99-106, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-18978949

RESUMO

In order to investigate any circannual and/or circaseptan variations in birth incidence and birth weight in Toda City (Japan), data on 4,411 consecutive births were obtained from the city's Maternity Hospital between 1 Jan 1999 and 31 Dec 2001. Data were analysed by cosinor separately for babies with birth weights in given ranges, and separately for boys and girls born at different gestational ages. A circannual rhythm was detected with statistical significance (P=0.047) for birth incidence of all vaginal deliveries, with an acrophase in the fall. A similar result for caesarean sections was of borderline statistical significance. A circaseptan component with a relatively consistent acrophase around midweek was of borderline statistical significance for birth incidence in some of the groups investigated. About-yearly and about-weekly variations were also found to characterize birth weight in some of the groups investigated.

17.
Scr Med (Brno) ; 78(2): 89-98, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-18985163

RESUMO

Circadian changes in mood have been described earlier. A positive affect (PA) has been separated from a negative affect (NA), as independent components in opposite admittedly subjective directions, a circadian rhythm characterizing both aspects. Herein, the time structure (chronome) of human mood is re-examined and extended from the circadian to the circaseptan domain by a meta-analysis of data on 196 clinically healthy students who filled out the positive (PA) and negative (NA) affective scale (PANAS), consisting each of 10-item mood scales. Both PA and NA are found by cosinor to be characterized by a circaseptan, circasemiseptan, and circadian variation. The circaseptan and circasemiseptan amplitudes are found to be larger than the circadian amplitude for NA, whereas the circadian amplitude is largest for PA. Complementing differences in relative circaseptan-to-circadian prominence between PA and NA are differences in the timing of the circadian, circasemiseptan, and circaseptan components of PA and NA. An even broader spectrum of rhythms may include a circadecadal modulation. With this qualification, the information on the time structure of mood provides endpoints to be considered in any attempt to optimize psychological well-being by making sleeping, dietary, and/or other lifestyle adjustments.

18.
Scr Med (Brno) ; 78(2): 83-88, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-19018289

RESUMO

The need for systematic around-the-clock self-measurements of blood pressure (BP) and heart rate (HR), or preferably for automatic monitoring as the need arises and can be met by inexpensive tools, is illustrated in two case reports. Miniaturized unobtrusive, as yet unavailable instrumentation for the automatic measurement of BP and HR should be a high priority for both government and industry. Automatic ambulatorily functioning monitors already represent great progress, enabling us to introduce the concept of eventually continuous or, as yet, intermittent home ABPM. On BP and HR records, gliding spectra aligned with global spectra visualize the changing dynamics involved in health and disease, and can be part of an eventually automated system of therapy adjusted to the ever-present variability of BP. In the interim, with tools already available, chronomics on self- or automatic measurements can be considered, with analyses provided by the Halberg Chronobiology Center, as an alternative to "flying blind", as an editor put it. Chronomics assessing variability has to be considered.

19.
Scr Med (Brno) ; 78(2): 75-82, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-19018290

RESUMO

The case report presented herein aims at promoting the awareness in medical, notably cardiological, practice of the importance of, first, collecting at least a week-long record of around-the-clock measurements of blood pressure (BP) and heart rate (HR) (and a much longer record if the 7 day record so indicates) and, second, of analysing the data chronobiologically in the light of reference values specified as a function of time, gender and age as a minimum. In addition to diagnosing deviations in a chronome (time structure)-adjusted mean value, a chronobiological approach identifies abnormalities in the variability of BP and/or HR, gauged by the circadian characteristics (double amplitude and acrophase, measures of the extent and timing of predictable change within a cycle) and by the standard deviation. A woman in presumably good health was 60 years of age at the start of intermittent monitoring over a 7 year span. The case report illustrates the extent to which a decision based on single BP readings and even on 24 hour averages may be misleading. Treatment based on an initial week-long monitoring may benefit from continued long-term monitoring.

20.
Scr Med (Brno) ; 78(2): 115-120, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19424512

RESUMO

As an extension of the chronobiological serial section, gliding spectra illustrate the changing time structure (chronome) of physiological, physical and/or other variables in a given frequency range. For this purpose, least squares spectra are computed over a specified interval (much shorter than the observation span) that is progressively displaced by a given increment throughout the entire record. Results can be displayed either as 3D charts or as surface charts, displaying the estimated amplitudes, percentage rhythms or ordering P-values at each trial period for each interval. The procedure is illustrated for the record of Wolf numbers as a gauge of solar activity and for the number of marriages and divorces in Japan during the past century. Major components in these time series show deviations in period length and relative prominence over time. Particularly in the case of non-stationary time series, gliding spectra offer themselves as useful tools to examine changes in time structure beyond a specific spectral component.

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