DIVERSITY AND HABITAT PROFILE OF THE SHALLOW WATER HOLOTHURIANS IN CAMOTES ISLANDS, CENTRAL PHILIPPINES

Species diversity and habitat profile of holothurians in Camotes Islands, Cebu Philippines were studied as baseline data for resource and ecological management. A 150 meter transect was laid in sandy, muddy and rocky substrates of the coastal barangays during the day and night assessments of the four municipalities of Camotes Islands which are San Francisco, Poro, Tudela and Pilar. Physico-chemical instruments and interview guide to the gleaners were used to gather data. Actual collection of specimen and other data was done in every 10 meter distance in the transect where a 1m quadrat was used. Results show that there are 20 species of holothurians belonging to 3 families namely Holothuriidae, Stichopodidae and Synaptidae. There are 2 species found in sandy substrate; 10 in muddy substrate; 2 in pure rocky substrate and 6 found in both rocky and muddy substrates. Results further show that there are 13 common species of Holothurians found in the four municipalities. The most diverse municipality is San Francisco which has 18 species followed by Poro (15); Pilar (14) and Tudela (13). For the distinct species, Holothuria rigida is found only in San Francisco followed by Pearsonothuria graffei (in Tudela and Pilar); Physico-chemical parameters like salinity, range from 23-38 ppt; temperature is 260C-350C, pH 4.5-8.0 both day and night assessments. Substrate grain size analysis shows that 100 microns dominate the amount of substrates in all the barangays, followed by 200 microns and then 400 microns. Keywords: Diversity, Habitat Profile, Holothurians, Camotes Island

Electrode positions, transformation coordinates for ECG reconstruction from S-ICD vectors.

The article contains data pertaining to the reconstruction of an 8-lead ECG from 2 subcutaneous implantable cardioverter defibrillator vectors. The location of electrodes on the precordium required for the data collection are detailed; the flow chart for patient selection and exclusion is shown; the summary data of the root mean square error (RMSE) (in microvolts) and Pearson r for the ECG transformation all cases and the pearson correlation for all the leads measured and reconstructed leads are also shown. Detailed background, methodology and discussion can be found in the linked research article

The Coordinated Universal Time (UTC)

International audienceCoordinated Universal Time (UTC) has considerably changed in recent years. The evolution of UTC follows the scientific and industrial progress by developing appropriate models, more adapted calculation algorithms, more efficient and rapid dissemination processes and a well defined traceability chain. The enormous technical progress worldwide has resulted in an impressive number of atomic clocks now available for UTC calculation. The refined time and frequency transfer techniques are approaching the accuracy requested for the new definition of the SI second. The more regular operation of primary frequency standards (PFS) increases the accuracy of UTC and opens a possible new development for time scale algorithms. From the metrological point of view all the ingredients are available for major improvements to UTC. Dissemination of UTC is done by the monthly publication of results in BIPM Circular T. This document makes a quality evaluation of local representations of UTC, named UTC(k), in national institutes, and other organizations, by giving the evolution of their offsets relative to UTC and their respective uncertainties. The clock models adopted and the time transfer techniques have progressively improved over the years, assuring the long-term stability of UTC. Each computation of UTC processes data over one month with five-day sampling and publication. A rapid solution of UTC (UTCr) has existed since 2013, and consists of the processing of daily sampled data over four consecutive weeks, computed and published weekly. It gives quick access to UTC, and allows participating laboratories to better monitor the offsets of their realizations to the reference UTC. The traditional monthly publication, containing results of all the laboratories contributing data to the BIPM for the computation of UTC was complemented after the establishment of the Mutual Recognition Arrangement of the International Committee on Weights and Measures (CIPM MRA). This time comparison, which has been the responsibility of the BIPM since 1988, added as a complement the key comparison on time defined by the Consultative Committee for Time and Frequency (CCTF) in 2006 as CCTF-K001.UTC, where the results published are those of national metrology institutes (NMIs) signatories of the CIPM MRA, or designated institutes (DIs). The traceability issues are formalized in the framework of the CIPM MRA. The development of time metrology activities in the different metrology regions, supports the actions of the BIPM time department to improve the accuracy of [UTC–UTC(k)], where the coordination with the Regional Metrology Organizations (RMOs) has a key role. This paper presents an overview of UTC

The Ornstein-Uhlenbeck process as a model for filtered white noise

The Ornstein–Uhlenbeck process is presented with its main mathematical properties and with original results on the first crossing times in the case of two threshold barriers. The interpretation of filtered white noise, its stationary spectrum and Allan variance are also presented for ease of use in the time and frequency metrology field. An improved simulation scheme for the evaluation of first passage times between two barriers is also introduced

Timescales at the BIPM

International audienceThis paper reviews the present status of the timescales established at the International Bureau of Weights and Measures (BIPM). We focus our attention on the calculation and the characteristics of Coordinated Universal Time (UTC) and present its applications