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Biomedical subjects

D Beal

Publications and source records attributed to D Beal.

17 recordsLinked to original sources
PubMed2002

Sources of formaldehyde, other aldehydes and terpenes in a new manufactured house.

Formaldehyde, less volatile aldehydes, and terpene hydrocarbons are generally the predominant air contaminants in new manufactured and site-built houses. This study was conducted to identify the major sources of these compounds in a typically constructed, new manufactured house and to evaluate several source reduction practices. Specimens of materials used within the house were collected. These were individually pre-conditioned for 19 +/- 4 days, and tested for emissions of formaldehyde and other target compounds using small-scale chambers. Several cabinetry materials, passage doors, and the plywood subfloor were the predominant sources of formaldehyde and other aldehydes. The plywood subfloor was the predominant terpene source. Whole-house emission rates for combined materials were predicted based on the emission factors and the corresponding material quantities. These predicted rates were compared with whole-house emission rates derived from measurements made at the house 3 months after its installation. For 10 of 14 target compounds including formaldehyde, the predicted and derived rates were within a factor of two. Four emission barriers applied to plywood were shown to reduce emission factors for formaldehyde, hexanal, and other aldehydes.

Air Pollution, Indoor↗
PubMed2000

Volatile organic compound concentrations and emission rates in new manufactured and site-built houses.

Concentrations of 54 volatile organic compounds (VOCs) and ventilation rates were measured in four new manufactured houses over 2-9.5 months following installation and in seven new site-built houses 1-2 months after completion. The houses were in four projects located in hot-humid and mixed-humid climates. They were finished and operational, but unoccupied. Ventilation rates ranged from 0.14-0.78 h-1. Several of the site-built houses had ventilation rates below the ASHRAE recommended value. In both manufactured and site-built houses, the predominant airborne compounds were alpha-pinene, formaldehyde, hexanal, and acetic acid. Formaldehyde concentrations were below or near 50 ppb with a geometric mean value for all houses of 40 ppb. Similarities in the types of VOCs and in VOC concentrations indicated that indoor air quality in the houses was impacted by the same or similar sources. Major identified sources included plywood flooring, latex paint and sheet vinyl flooring. One site-built house was operated at ventilation rates of 0.14 and 0.32 h-1. VOC emission rates calculated at the two conditions agreed within +/- 10% for the most volatile compounds. Generally, the ratios of emission rates at the low and high ventilation rates decreased with decreasing compound volatility. Changes in VOC emission rates in the manufactured houses over 2-9.5 months after installation varied by compound. Only several compounds showed a consistent decrease in emission rate over this period.

Air Pollution, Indoor↗
PubMed1996

[Hepatic hamartoma in adults. Apropos of a case documented by MRI].

A mixed hamartoma of the liver in a 39 year old man is reported. Abdominal ultrasound revealed a 4 cm inhomogeneous echogenic mass with acoustic shadowing. MRI T1 weighted images showed a inhomogeneous low intensity mass with lower gadolinium enhancement than normal liver, a moderate low signal intensity on proton density weighted images, and heterogeneous isosignal intensity on T2 weighted images. Peripheric calcifications were found on pathologic examination.

Adult↗
PubMed1994

Anatomical basis of a fascio-cutaneous pedicle flap based on the infero-lateral collateral artery of the leg.

An anatomical study of 30 cases has been performed on the vascularisation of the distal third of the antero-lateral compartment of the leg, with particular reference to the relations of the infero-lateral collateral artery of the anterior tibial artery, the perforating branch of the peroneal artery, and the antero-lateral malleolar artery. A fascio-cutaneous pedicle flap based on the infero-lateral collateral artery is described noting that the superior, anterior, and posterior limits are similar to those of the lateral supramalleolar flap of Masquelet. The inferior limit of this new flap is 15 mm distal to the site of emergence of the perforating branch of the peroneal artery. The advantages of this flap are; a large surface area for cover, antegrade vascularisation, and no significant vascular sacrifice. The distal half of the calf can be covered both medially and posteriorly as well as the proximal half of the dorsum of the foot, the medial and lateral arch areas, the perimalleolar region, and the region behind the Achilles tendon. The flap requires the presence of the infero-lateral collateral artery of the tibialis anterior which can be confirmed either peroperatively or preoperatively by angiography.

Collateral Circulation↗
PubMed1993

[GUEPAR total trapeziometacarpal prosthesis in the treatment of arthritis of the thumb. 36 case reports].

The authors review a series of 36 total GUEPAR trapezometacarpal arthroplasties, performed between 1981 and 1990 in 32 patients, with a Dell stage III or IV carpometacarpal arthritis of the thumb (primary arthritis = 34 cases; secondary arthritis: 2 cases, 1 case of chondrocalcinosis, 1 case of osteochondromatosis). Scaphotrapezial arthritis present in 7 cases is not a contraindication to total arthroplasty. The mean follow-up period was 3 and a half years, with a range of 1 to 9 years. Functional results were considered to be good in 89%, without limitation of activity. X-ray study shows: 1) A radioclinical concordence in 64% of cases with good clinical and X-ray results, stable in the long term. 2) A radioclinical discordance in 22% of cases with good functional result but mobilisation of metacarpal stem. 3) Failure in 5 cases (14%) with unsealing and trapezial fracture. This radioclinical study yields two failure factors: preoperative destruction of trapezium in all the failures and these cases are now a contraindication to the prosthesis and inadaptation between stem arthroplasty and metacarpal cavity. This study supports total arthroplasty in trapezometacarpal arthritis of the thumb: III or IV Dell's stage, with preserved trapezium configuration.

Adult↗
PubMed1991

Anatomical basis of neurotisation of the median nerve in the hand by the radial nerve.

The sensory sequelae after lesions of the median nerve cause difficulties in treatment since few sensory transfers are available. Neurotisation of the median by sensory branches of the radial nerve have aroused little interest although they have already been used by some authors after anastomosis at the wrist or through the first or second interosseous spaces. Based on what was originally a purely anatomic study, our interest was directed to the possibilities of performing more distal neurotisation for the treatment of sensory disorders of limited extent. The chief object was to obtain faster sensory reinnervation. 30 hands were dissected and a radial branch was defined as suitable for neurotisation whose diameter approximated that of its palmar digital homolog. Only those findings constantly observed in analysis of the hands studied were taken into account. It is therefore possible to reliably define the type and site of the routes of approach as well as the sensory branches suitable for neurotisation.

Hand↗
PubMed1991

[Bundled central medullary bone wiring. Method of choice in the treatment of fractures of the neck of the fifth metacarpal necessitating a reduction. 30 cases].

The authors present a short series of 30 displaced fractures of the neck of the fifth metacarpal. All fractures were treated by K-wire nailing according to the method described by Fourcher in 1976. The good results confirm the advantages of this technique, allowing early mobilization and rehabilitation. The poor results are due to faults in the use of the method, and the authors emphasize these technical errors.

Adolescent↗
PubMed1984

A cross-validation of Paulson's discriminant function-derived scales for identifying "at risk" child-abusive parents.

Paulson, Afifi, Chaleff, Liu, & Thomason (1975) developed a series of special subscales from the MMPI for identifying individuals who are at risk for child-abusive behavior. The initial results were highly encouraging, with the scales correctly identifying 93 to 100% of the subjects in their sample. Unfortunately, Paulson et al. (1975) failed to cross-validate their findings before publication. When the six scales were cross-validated on an independent sample from the population of child-abusing parents, significant shrinkage in the accuracy of prediction was found. The use of the special subscales for identifying "at risk" parents in prenatal clinics, pediatric clinics, pediatric clinics and mental health centers as originally suggested by Paulson and his colleagues is seriously questioned.

Adult↗
PubMed1982

Development of standards of performance by mentally retarded children.

The ability of moderately mentally retarded children to set self-performance standards was investigated. We hypothesized that (a) subjects who received training based on the relational concept of "between" would be able to acquire and retain superior standard-setting performance compared to nontrained control subjects, and (b) those receiving this training would be able to generalize their superior standard-setting performance to a task involving more variable feedback as well as to a conceptually more abstract task. Results indicated that the subjects learned and retained concepts that allowed them to set appropriate or realistic self-performance standards. Further, retarded subjects were able to set appropriate standards when given less restricted feedback than was given during the initial training. On a more abstract picture-matching task, no significant differences were found between the two groups.

Concept Formation↗
PubMed1978

The organization of a human milk bank in a North Q ueensland hospital.

The development of a human milk bank with nursing mothers as donors of human milk is described. Breast milk is collected manually, and as aseptically as possible, by the mother in the privacy of her home, and the milk is transported frozen to the milk bank by a member of the Nursing Mothers' Association of Australia. A sample of expressed milk is also collected and sent to the Microbiology Department of the Australian Government Health Laboratory for bacteriological examination. The milk bank is suitably located in the paediatric ward of the Townsville General Hospital. Human milk which has been classed as bacteriologically safe is given untreated to hospitalized infants in preference to formula milk. The result is a human milk bank which is administered under medical and microbiological control.

Australia↗