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Biomedical subjects

G Villegas

Publications and source records attributed to G Villegas.

25 records · Page 2Linked to original sources
PubMed1978

A before and after for tonogenesis.

The development of tone in Panjabi from the loss of certain consonants has often been cited as an instance of the consonantal origins of a tonal system. Acoustic data demonstrating the correlation between Panjabi tones and Hindi consonants are presented. Panjabi high tone matches a higher fundamental frequency on a Hindi vowel preceding a breathy voiced consonant. Panjabi low tone matches a lower fundamental frequency on a Hindi vowel following a breathy voiced consonant. It is interesting that the data exhibit the spread of the consonantal effect throughout the entire word.

Acoustics↗
PubMedDate not supplied

Seventy-three nuclear DNA polymorphisms in a Spanish population and a comparison with ten other populations.

An anthropologically well-defined Spanish sample from La Alpujarra (SE Spain) was analyzed for 73 nuclear DNA polymorphisms. The population was chosen on the basis of available information on its history and demographic characteristics making it suitable for comparisons with data from North African populations. The Moslem invasion in this area was longer than anywhere in the Iberian Peninsula (more than nine centuries). The markers analyzed have been studied previously in 10 human populations from different continents. The Alpujarrenian population was checked for these markers and it is the one with the highest number of chromosomes analyzed. Two new alleles were sized and heterozygosity levels were very similar to other European populations. Genetic distances closely matched geographical relationships both with neighbor joining tree and principal component analysis. Allele distributions revealed specific associations with some populations. This work reveals the importance of these markers for evolutionary studies of human populations.

Africa, Northern↗
PubMedDate not supplied

Microcomputer-based coronary care unit central station.

A four-bed central station that can be connected to any commercial intensive-care bedside monitor was developed. The system is based on a personal computer (IBM-AT compatible) as a local unit and on a microcontroller Intel 8031 as a remote unit. Four ECG signals are low-pass filtered, multiplexed, sampled at 256-Hz per channel, 8-bit A/D converted, preprocessed, and converted to a serial format RS-232 by the remote unit. The real-time display of the signals is at the standard speed of 25 and 50 mm/sec. Heartrate, alarms, trend plots, and general patient data are shown on an Olivetti M280 and EGA 13'' color monitor as the local unit. The communication speed was set at 57.6 Kbaud full duplex. Additionally, to reach standard monitoring sweep rates using a 13'' screen with 640 x 350 pixels, an ECG data-compression algorithm was implemented in the remote unit. This unit can support up to eight input channels and can work with any personal computer, via RS-232, with the appropriate software. It also allows other signal preprocessing software that could be developed, such as QRS detection or ST segment quantification, to be loaded into its random access memory and to be run under PC command. The development of this system demonstrated the use of a widespread piece of commercial equipment, the PC, in a very specific application, CCU monitoring, assuring low-cost system implementation. This feature is particularly attractive in upgrading existing CCU units in less developed countries.

Biomedical Engineering↗