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PubMed1988

Biometric outcomes of a geriatric health promotion programme.

A geriatric health promotion programme was conducted to determine biometric changes in cardiovascular, nutritional and musculoskeletal status. Sixty-seven older adults participated in the study. The experimental group of 34 elderly subjects showed statistically significant increases in flexibility and high density lipoprotein with significant decreases in resting pulse rate, blood pressure, total cholesterol, weight and skinfold measures. The overall results of the wellness programme showed significant improvements in the physical health status of older adults.

Aged↗
PubMed1983

Effects of gingival curettage when performed 1 month after root instrumentation. A biometric evaluation.

The purpose of the present study was to evaluate biometrically the periodontal response to gingival curettage. 15 subjects having suprabony pockets were selected. Gingival Index (GI) was initially determined for the selected teeth. Measurements of probing depth, and the distance from the free gingival margin to the cemento-enamel junction were also taken at that time, as well as immediately after scaling and root planing of the selected teeth. 4 weeks after scaling and root planing, the clinical parameters were recorded. A split mouth design was used to select 2 quadrants of the mouth in which gingival curettage was to be performed. Immediately after, experimental measurements were again recorded. 5 weeks after gingival curettage, gingival inflammation, probing depth and the location of the free gingival margin were recorded for the last time. All data were analyzed statistically. It was shown that gingival inflammation, the distance from the free gingival margin to the cemento-enamel junction, and the probing depth were reduced after 4 and 9 weeks. The level of clinical attachment improved after 9 weeks. All these changes were statistically significant. These results were observed after scaling and root planing, as well as after scaling, root planing and gingival curettage. No differences were found between both treatment modalities in any of the parameters analyzed. Gingival curettage did not improve the condition of the periodontal tissues more significantly than scaling and root planing.

Adult↗
PubMed1996

Fetal ultrasonography: normal biometric ranges in the baboon (Papio hamadryas).

Normal biometric ranges for fetal growth in a captive breeding baboon (Papio hamadryas) colony are described. Measurements include crownrump length, biparietal diameter, binocular distance, head circumference, abdominal circumference, femur length and amniotic fluid index. The pattern of fetal growth is compared with other baboon subspecies and man. The uses and limitations of such data for breeding colony management and optimum utilisation of experimentally derived data are discussed.

Animals↗
PubMed2006

Fetal ultrasonography: biometric data from four African primate species.

BACKGROUND: Nonhuman primates are raised in large numbers in research centers and zoos. Reproductive monitoring is required to improve breeding performances. Ultrasonography is a safe method to determine gestational age and to estimate the date of parturition. However only few data are available in nonhuman primates. METHODS: Fetal biometric data were obtained throughout pregnancy on four African primate species, namely chimpanzee, gorilla, mandrill and patas monkey. Measurements included biparietal diameter, transverse abdominal diameter, femur and humerus length, external interorbital diameter, and fetal heart rate. Curves established from these data were compared with previously published data in chimpanzees and gorillas and with those for humans and other closely related primate species. RESULTS: The curves for the different hominids were very similar, while those for mandrills more closely resembled baboons and data for patas monkeys were comparable to those for macaques. CONCLUSIONS: These data, by providing a tool to evaluate precise gestational age, will be useful for centers raising these four primate species.

Animals↗
PubMedDate not supplied

Ultrasonographic and computed tomographic examinations of the avian eye: physiologic appearance, pathologic findings, and comparative biometric measurement.

Ultrasonography (US) and computed tomography (CT) were performed after routine ophthalmologic and ophthalmoscopic examinations in 190 eyes of six various diurnal (common buzzard [Buteo buteo L., 1758], n = 20; common kestrel [Tinnunculus tinnunculus L., 1758], n = 20) and nocturnal raptor species (barn owl [Tyto alba L., 1758], n = 22; tawny owl [Strix aluco L., 1758], n = 8; long-eared owl [Asio otus L., 1758], n = 5; horned owl [Bubo bubo L., 1758], n = 1); and domestic pigeons (Columba livia, Gmel., 1789; n = 19), with a total of 95 individuals. Pathologic findings such as lens subluxation and luxation, intravitreal hemorrhage, detached retina, post-traumatic partial sequestration, or malformation of the pecten could be demonstrated with diagnostic imaging tools, while opacities of cornea or lens constrained direct ophthalmoscopic examination. The results proved US to be a quick noninvasive imaging technique for detailed ocular diagnoses. CT provided detailed information of the bony skull and bony scleral rings as well as adequate visualization of shape, size, and margination of the eye and lens. Nevertheless, CT was unable to differentiate subtle structures within the vitreous like the pecten oculi or hemorrhage. Biometric measurements were carried out to objectify imaging results. Results showed good correlation of depth and width of the anterior eye chamber, lens and vitreous, length of the bulbus, and the pecten but no correlation of cornea and posterior wall thickness was found.

Animals↗
PubMed1975

Biometric correlations of corneal thickness.

Central corneal thickness, depth of anterior chamber, thickness of lens, length of vitreous, axial length, applanation (Goldmann) and indentation (Schiotz) tension and rigidity (Friedenwald) were determined in three groups of patients; (1) 16 patients with glaucoma simplex, (2) 25 patients with ocular hypertension, and (3) 26 patients with fibrillopathia epitheliocapsularis (so-called pseudoexfoliation of the lens). Average data and computed correlations between the parameters are given in tabular form. Corneal thickness was normal in glaucoma simplex, but significantly increased in ocular hypertension. Corneal thickness was positively correlated to applanation tension but not to indentation tension, nor to any other of the studied parameters. It is suggested that corneal thickness can be considered as a biometric parameter which yields new information about the eye not covered by the conventional parameters.

Anterior Chamber↗
PubMed1976

Further data on biometric correlations of central corneal thickness.

Central corneal thickness measured in 126 young men aged from 18-21 years was correlated to a number of ocular and other parameters. The frequency distribution was skewed towards the lower end, but the deviation could not be statistically supported. No correlation between corneal thickness and birth weight was found. Other characteristics not correlated in this material to corneal thickness were corneal astigmatism, refraction, visual acuity, optic disc and retinal abnormalities, red-green colour vision defects, ABO and rhesus blood-groups, EEG abnormalities, chromosomal abnormalities, hearing defects, ear abnormalities and quality of the hair. The findings in this study, although mainly of negative character, stress the relative independence of the central corneal thickness as a biometric parameter.

ABO Blood-Group System↗
PubMed2005

Choroidal expansion as a mechanism for acute primary angle closure: an investigation into the change of biometric parameters in the first 2 weeks.

BACKGROUND/AIM: Choroidal expansion with anterior movement of the lens was recently proposed as a mechanism for acute primary angle closure (APAC). The aim of this study was to compare the biometric parameters, central anterior chamber depth, limbal chamber depth, lens thickness, and lens position, within 24 hours of presentation and 2 weeks later in eyes with APAC. METHODS: This was a prospective observational case series of 41 subjects with APAC. Subjects who presented with APAC were treated with medical therapy followed by laser iridotomy (LI) in both eyes once the acute attack was broken. Ocular biometry was performed in affected and fellow eyes before LI (baseline) and then 2 weeks later. Optical pachymetry was used to measure central anterior chamber depth (ACD) and the limbal chamber depth (LCD) was graded at the slit lamp. A-scan ultrasound was used to measure lens thickness (LT) and axial length (AL). Lens position (LP) was defined as ACD +(1/2)LT. RESULTS: The majority of subjects were Chinese (83%) and female (61%), and the mean age was 60.4 (SD 10.3) years. In affected eyes, the ACD was 1.81 (0.29) mm before and 1.80 (0.28) mm 2 weeks after LI (p = 0.63), while in fellow eyes, the ACD was 1.83 (0.29) mm and 1.81 (0.38) mm, respectively (p = 0.21). There was no significant change in lens position, relative lens position, or axial length in both affected and fellow eyes over the 2 weeks. CONCLUSIONS: There was no change observed in central anterior chamber depth, lens thickness, or lens position at the time of the acute attack compared to 2 weeks later in both APAC affected and fellow eyes. The findings do not support the hypothesis of lens movement due to choroidal expansion in APAC.

Acute Disease↗
PubMed2002

Biometric gonioscopy and the effects of age, race, and sex on the anterior chamber angle.

AIM: To utilise a novel method for making measurements in the anterior chamber in order to compare the anterior chamber angles of people of European, African, and east Asian descent aged 40 years and over. METHODS: A cross sectional study on 15 people of each sex from each decade from the 40s to the 70s, from each of three racial groups-black, white, and Chinese Singaporeans. Biometric gonioscopy (BG) utilises a slit lamp mounted reticule to make measurements from the apparent iris insertion to Schwalbe's line through a Goldmann one mirror goniolens. The main outcome measures were BG measurements of the anterior chamber angle as detailed above. RESULTS: There was no significant difference in angle measurement between black, white, and Chinese races in this study. However, at younger ages people of Chinese race appeared to have deeper angles than white or black people, whereas the angles of older Chinese were significantly narrower (p = 0.004 for the difference in slope of BG by age between Chinese and both black and white people). CONCLUSION: The failure to detect a difference in angle measurements between these groups was surprising, given the much higher prevalence of angle closure among Chinese. It appears that the overall apparent similarity of BG means between Chinese and Western populations may mask very different trends with age. The apparently more rapid decline in angle width measurements with age among Chinese may be due to the higher prevalence of cataract or "creeping angle closure." However, longitudinal inferences from cross sectional data are problematic, and this may represent a cohort phenomenon caused by the increasing prevalence of myopia in the younger Singaporean population.

Adult↗
PubMed1998

Biometric pre-operative evaluation of ocular axial length in patients subjected to corneal transplantation.

In cases of keratoconus and consequent penetrating keratoplasty, the refractive requirements of the patient determine the dimensions of the donor button and the receiving wound size. The pre-operative biometric evaluation of the axial parameters may induce the surgeon to choose an oversized button to obtain the right curvature of the cornea and avoid hypermetropia. In this study we present 20 patients transplanted between 1993 and 1995, 13 female, 7 male, aged between 23 and 45 years. These cases demonstrate the utility of this easy and economic technique.

Adult↗
PubMed1991

Biometric analysis of the mandibles of Papio anubis and Cercopithecus aethiops.

Six biometric measurements were recorded from dry mandibles of 53 Papio anubis and 84 Cercopithecus aethiops: intercondylar width, intercoronoid width, intermolar width (IMW), mesiodistal width of the condyles, height of the occlusal table and anteroposterior length of the chewing surface from P4 to M3 (CL). The mean values and correlation matrices of these variables show that, despite the difference in size, the overall shape of the mandible in male and female is similar within species. The principal component analysis shows that in P. anubis the six variables contribute almost equally to the first component (75% of total variance), suggesting that the large mandible may be force related because of the greater mechanical forces required for chewing certain foods. In C. aethiops, the contribution of IMW and CL is less in the first component (52.7% of total variance), suggesting that the biochemical forces of mastication are more complex to adapt the mandible to a shorter muzzle and a particular diet.

Animals↗
PubMed1993

Ocular growth in the fetus. 1. Comparative study of axial length and biometric parameters in the fetus.

The knowledge of ocular growth during fetal life, when compared with other fetal biometric parameters, could not only provide a better definition of malformation syndromes but could also give a better understanding of certain pathological processes in premature babies and in newborns. As the literature concerning prenatal ocular dimensions contains few data, the aim of this study was to measure the axial length of the globe (AL) in fetuses and compare this measurement with their gestational age, weight, height, head circumference (HC) and thoracic circumference (TC) in order to compile a reference table. In the present study, 76 globes from 38 fetuses (18-41 weeks gestational age) from the Department of Pathology (Timone University Hospital, Marseille) were examined. Ultrasonography A and B were used to measure the AL, and a pathological examination determined fetal weight, HC, TC and height. We were interested to find out which of the parameters studied would give the best correlation with ocular growth. Statistical analysis showed that HC remained the most discriminant factor and correlated best with ocular growth. We thus obtained an equation for ocular size according to HC that could serve as a basis for detecting pre- or postnatal ocular defects.

Anthropometry↗
PubMed1990

Biometric genetic analysis of blood pressure in the spontaneously hypertensive rat.

The spontaneously hypertensive rat is the most widely studied animal model of essential hypertension, yet the genetics of transmission of high blood pressure in this strain have not been clearly defined. It has been proposed that in the spontaneously hypertensive rat, blood pressure follows a simple additive mode of inheritance and that the hypertension is primarily determined by a single major locus. To investigate the genetics of transmission of increased blood pressure in the spontaneously hypertensive rat, we performed a biometric genetic analysis of multiple, direct measurements of arterial pressure in unanesthetized, unrestrained rats derived by crossing spontaneously hypertensive rats with two different inbred normotensive strains, the Charles River Wistar-Kyoto rat and the Lewis rat. In both crosses, approximately 60% of the variation in blood pressure could be assigned to genotypic variation. The data fit an additive-dominance model of inheritance in which alleles decreasing blood pressure were partially dominant. Thus, in offspring derived from crosses between spontaneously hypertensive rats and Wistar-Kyoto rats or spontaneously hypertensive rats and Lewis rats that are raised under ordinary laboratory conditions, increased blood pressure is not determined by simple additive effects of alleles at a single major locus. The current findings are consistent with the possibility that in the spontaneously hypertensive rat, hypertension may arise from mutations in alleles that ordinarily act in a dominant fashion to suppress blood pressure.

Animals↗
PubMed1995

Long-term effects of the Herbst appliance on the dental arches and arch relationships: a biometric study.

The purpose of this study was to evaluate biometrically the treatment and post-treatment effects of the Herbst appliance on the dental arches and arch relationships. The sample consisted of 53 Class II, division 1 malocclusion patients (33 boys and 20 girls) treated with the Herbst appliance. The mean age of the patients before treatment was 12.5 years (SD = 1.2 years). Dental casts were analysed before treatment, after treatment, 6 months post-treatment and at the end of the growth period (5-10 years post-treatment). The following variables were assessed: sagittal molar and canine relationships, overjet, overbite, maxillary and mandibular arch perimeters, and inter-molar and inter-canine dental arch widths. During treatment, the overjet, overbite, and sagittal molar relationship were overcorrected in most of the cases, while the sagittal canine relationship was normalized. The maxillary and mandibular arch perimeters increased during treatment, as did dental arch widths (molar and canine). In the long-term (mean = 6.7 years after treatment), Herbst appliance treatment resulted in a normal or over-corrected sagittal molar relationship in 79 per cent and a normal canine relationship in 68 per cent of the cases. Eighty-three per cent of the subjects had an overjet of 4.5 mm or less. In the long-term, the arch perimeters seemed to follow a normal dental development pattern. The increase of the upper molar and canine dental arch widths during treatment remained virtually stable whilst the lower intermolar arch widths seemed unaffected by treatment.

Adolescent↗
PubMed2006

A biometric and ecologic comparison between Artemia from Mexico and Chile.

BACKGROUND: A preliminary biometric and ecologic database for the brine shrimp Artemia from Mexico and Chile is presented. The area abounds in small and seasonal ponds and large inland lakes, the latter mainly located in Mexico, although relatively large and isolated lakes are found in complex hydrological settings in pre-high plateau areas of Chile. This paper summarizes research efforts aimed at the localization, characterization, and evaluation of the aquaculture potential of Artemia populations in Mexico and Chile, which exhibit great habitat diversity (ponds, salterns, coastal lagoons, sea arms, coastal and inland lakes), contrasting weather conditions and different levels of isolation and human intervention. RESULTS: This study covered locations between 29 degrees north latitude (Baja California, Mexico) to 50 degrees south latitude (Puerto Natales, Chile). Biological characteristics considered are species name, reproductive mode, cyst diameter, chorion thickness, and nauplius length, whereas ecological data include pond size, pH, salinity, temperature, and water ionic composition. Artemia franciscana is the only species found in Mexico, it exists together with A. persimilis in Chile, though separated geographically. Ecological differences in habitat exist between both regions but also within countries, a pattern particularly clear with regard to water composition. Surprisingly, a Mexican (Cuatro Ciénegas, A. franciscana) and a Chilean location (Torres del Paine, A. persimilis) share habitat characteristics, at least for the period when data were collected. The discriminant analysis for cyst diameter and nauplius length shows that Artemia from only one location match in cyst diameter with those from San Francisco Bay (SFB) (Point Lobos), and one (Marquez) is far apart from SFB and all the others. The Chilean locations (Pampilla, Cejar, Cahuil, Llamara, Yape) share cyst diameter, but tend to differ from SFB. The remaining Mexican locations (Juchitan, Ohuira, Yavaros) are well separated from all the others. With regard to nauplii length, populations tend to distribute in a relatively random manner, being Marquez the location differing the most in cyst diameter from SFB. CONCLUSION: This database will contribute to the knowledge of radiation centers and serves as a baseline for further biogeographic studies, population characterization, management, and monitoring of Artemia biodiversity. Likewise, the impact of colonization and translocations for aquaculture purposes can be better assessed with a baseline for reference. Mexico and Chile exemplify the need to increase and further integrate regional information to tackle fundamental problems underlying practical utilization of Artemia.

Journal Article↗
PubMed2005

Wavelet packet correlation methods in biometrics.

We introduce wavelet packet correlation filter classifiers. Correlation filters are traditionally designed in the image domain by minimization of some criterion function of the image training set. Instead, we perform classification in wavelet spaces that have training set representations that provide better solutions to the optimization problem in the filter design. We propose a pruning algorithm to find these wavelet spaces by using a correlation energy cost function, and we describe a match score fusion algorithm for applying the filters trained across the packet tree. The proposed classification algorithm is suitable for any object-recognition task. We present results by implementing a biometric recognition system that uses the NIST 24 fingerprint database, and show that applying correlation filters in the wavelet domain results in considerable improvement of the standard correlation filter algorithm.

Algorithms↗
PubMed2005

Eye-tracking architecture for biometrics and remote monitoring.

Eye tracking is one of the latest technologies that has shown potential in several areas, including biometrics; human-computer interactions for people with and without disabilities; and noninvasive monitoring, detection, and even diagnosis of physiological and neurological problems in individuals. Current noninvasive eye-tracking methods achieve a 30-Hz rate with a low accuracy in gaze estimation, which is insufficient for many applications. We propose a new noninvasive optical eye-tracking system that is capable of operating at speeds as high as 6-12 kHz. A new CCD video camera and hardware architecture are used, and a novel fast algorithm leverages specific features of the input CCD camera to yield a real-time eye-tracking system. A field-programmable gate array is used to control the CCD camera and to execute the operations. Initial results show the excellent performance of our system under severe head-motion and low-contrast conditions.

Algorithms↗