What's the difference between epoch and ordovician?

Epoch


Definition:

  • (n.) A fixed point of time, established in history by the occurrence of some grand or remarkable event; a point of time marked by an event of great subsequent influence; as, the epoch of the creation; the birth of Christ was the epoch which gave rise to the Christian era.
  • (n.) A period of time, longer or shorter, remarkable for events of great subsequent influence; a memorable period; as, the epoch of maritime discovery, or of the Reformation.
  • (n.) A division of time characterized by the prevalence of similar conditions of the earth; commonly a minor division or part of a period.
  • (n.) The date at which a planet or comet has a longitude or position.
  • (n.) An arbitrary fixed date, for which the elements used in computing the place of a planet, or other heavenly body, at any other date, are given; as, the epoch of Mars; lunar elements for the epoch March 1st, 1860.

Example Sentences:

  • (1) The adaptive filter processor was tested for retrospective identification of artifacts in 20 male volunteers who performed the following specific movements between epochs of quiet, supine breathing: raising arms and legs (slowly, quickly, once, and several times), sitting up, breathing deeply and rapidly, and rolling from a supine to a lateral decubitus position.
  • (2) The results indicate that the different EEG frequency bands during a given EEG epoch are generated by neural populations in different brain locations.
  • (3) The majority of classes have over 200 discrete epochs.
  • (4) By means of the adaptive estimation of the variance of respiratory movements, an amplitude-time window is calculated to choose between epochs with breaths and apnoea.
  • (5) Speaking in Athens last November, the Italian philosopher Giorgio Agamben discussed an epochal transformation in the idea of government, "whereby the traditional hierarchical relation between causes and effects is inverted, so that, instead of governing the causes – a difficult and expensive undertaking – governments simply try to govern the effects".
  • (6) The effect was chiefly on the frequency of state changes and less on epoch durations.
  • (7) The author rejects the proposition, encountered in some parts of the psychoanalytic and social-science literature, that certain types of disturbances correspond to certain epochs or forms of society.
  • (8) In overt schizophrenics, late epoch stability was low in all EPs.
  • (9) EPOCH was administered intravenously once a week with the dosage of 3,000-9,000 IU for 8 weeks.
  • (10) The prolonged neurophysiological effects of stimulation may allow the use of maximum effective intervals between optimal epochs of stimulation so that any cerebellar damage can be minimized.
  • (11) Median heart and respiratory rate, respiratory variability, and median extent of three types of heart rate variation were determined for each epoch, and the minute-by-minute correlations between seven pairs of parameters were determined for quiet sleep, rapid eye movement sleep, and waking in each recording.
  • (12) The short-term variability of the selected EEG measures and their suitability as a sample estimate were assessed by computing the coefficient of variation from all selected epochs of a given subject at baseline.
  • (13) But what use are such skills when addressing the enormity of this new epoch?
  • (14) It is argued that, during the first two and last periods, all quantities of genetic interest, such as the gametic frequencies, the mean fitness, the linkage disequilibrium, and the linkage disequilibrium ratio, Z, change with time in essentially the same manner, characteristic of the particular epoch concerned and determined in this paper, and therefore, when quasilinkage equilibrium occurs, it is a transitional phenomenon.
  • (15) Evidence for the hypothesis was found only during the EEG-epoch one second before the answer.
  • (16) The automatic analysis scored fewer epochs as stages wake, rapid eye movement (REM), and 2 and more as stages 1, 3, and 4.
  • (17) Finally, an epoch by epoch analysis is described, with the aim of achieving a more detailed evaluation of the intergroup variability.
  • (18) In the first set of experiments (n = 8), placebo or CS (30 mg) was given, followed by four 15-min epochs of alveolar hypoxia (8% O2, 5% CO2, 87% N2) each separated by 30 min of alveolar normoxia (21% O2).
  • (19) Two averaging strategies were assessed: (1) averaging the entire pre- and poststimulus epoch point for point across individuals and (2) averaging the voltage of Pa at the latency of Pa for each individual.
  • (20) Finally, it is demonstrated that the probability of a false-positive decision may increase by an order of magnitude if the Rayleigh test is not performed once, for a fixed number of epochs specified in advance, but is carried out repeatedly during an ongoing experiment until either one of the tests indicates the presence of an evoked response or the upper limit for the number of epochs is exceeded.

Ordovician


Definition:

  • (a.) Of or pertaining to a division of the Silurian formation, corresponding in general to the Lower Silurian of most authors, exclusive of the Cambrian.
  • (n.) The Ordovician formation.

Example Sentences:

  • (1) Furthermore, the identification of vertebrate hard tissues in the oral elements of conodonts extends the earliest occurrence of vertebrate hard tissues back by around 40 million years, from the Middle Ordovician (475 million years ago) to the Late Cambrian (515 million years ago).
  • (2) His message remains blunt today: “Show me a scientist who claims there is no population problem and I’ll show you an idiot.” Earth’s five previous mass extinctions End-Ordovician, 443 million years ago A severe ice age led to sea level falling by 100m, wiping out 60-70% of all species which were prominently ocean dwellers at the time.
  • (3) – Cambrian, Ordovician, Silurian, Devonian, Carboniferous, Permian, Triassic, Jurassic, Cretaceous … 'What will survive of us is love', wrote Philip Larkin.
  • (4) It begins with a discussion of the origins of the craniofacial tissues in the dentine and bone of the dermal denticles of the Ordovician jawless vertebrates, followed by a brief discussion of the mechanisms responsible for the evolution of the jaws and the origin of vertebrate dentition.
  • (5) In each of the following, more than half the Earth’s species disappeared: 1 End-Ordovician, 443 million years ago.
  • (6) Paleontological data indicate that the earliest recognizable vertebrate remains, bone fragments of Upper Cambrian and Lower Ordovician heterostracan fishes, were deposited in a marine situation.
  • (7) Dentine, the bone of attachment associated with dentine, the basal bone to which dermal denticles are fused and cartilage of the Ordovician agnathan dermal exoskeleton were all derived from the neural crest and not from mesoderm.
  • (8) Cartilage (unmineralized) can be inferred to have been present in heterostracans and osteostracans, and globular mineralized cartilage was present in Eriptychius, an early Middle Ordovician vertebrate unassigned to any established group, but assumed to be a stem agnathan.
  • (9) The contemporaneous appearance of cellular and acellular bone in heterostracans and osteostracans during the Ordovician provides no clue as to whether one is more primitive than the other.

Words possibly related to "ordovician"