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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.

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.

Putative circadecadal modulations of a circannual variation in diastolic blood pressure are explored in a still accumulating 35 year record of self-measurements by a clinically healthy man. Analyses of monthly means by gliding spectra, one-way analysis of variance (ANOVA), and cosinor were carried out after removing data collected during travel across time zones or during illness. An about yearly change in diastolic blood pressure may or may not be detected with statistical significance by cosinor or ANOVA, apparently as a function of solar cycle number and/or stage. It appears to be, however, 1 year synchronized in the entire span analysed as a whole. A given variable such as diastolic blood pressure may be characterized by multifrequency rhythms that may intermodulate, so that findings in different stages of cycles with the lowest (e.g., circadecadal) frequency mapped may determine different outcomes in cycles with higher frequencies, such as circannuals.

In order to investigate infradian aspects of sudden death, the daily incidence of 70,531 cases recorded in response to a call for an ambulance during 3 years (1979-1981) in Moscow, Russia, were re-analysed, focusing on multiseptans (components with periods of 7 days and/or multiples thereof). Apart from a prominent yearly and half-yearly variation in the daily incidence of sudden death, least squares spectra revealed the presence of about-weekly and two-weekly components. The about 15.2-day variation was validated by nonlinear least squares and shown to differ in period length from that found in the local index of geomagnetic activity, K. This result suggests that apart from any geomagnetic influence on sudden death, changes in lifestyle (such as alcohol consumption) associated with the twice-a-month salary schedule may affect the occurrence of sudden death. Such a component is not prominently seen for the incidence of other cardiovascular conditions recorded in the same database. The weekly pattern of sudden death, peaking on Saturdays, also differs from those of other cardiovascular conditions, characterized by a higher daily incidence on Mondays. The possibility to now record events in cardioverter-defibrillators offers an opportunity to explore broad chronomes of potentially lethal arrhythmia that may lead to a better understanding of underlying triggers, so that novel countermeasures may be designed and implemented.

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.

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.