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Biomedical subjects

L M dos Santos

Publications and source records attributed to L M dos Santos.

8 recordsLinked to original sources
PubMed2001

Aerobic biotransformation of 4-fluorocinnamic acid to 4-fluorobenzoic acid.

The biotransformation of 4-fluorocinnamic acid (FCA) using non-acclimated industrial activated sludge was investigated. FCA is a common intermediate in organic synthesis, and it is often present in aqueous waste streams. Hence, the biotransformation reactions this compound undergoes when exposed to activated sludge micro-organisms should be understood before waste streams are sent to biological wastewater treatment plants (WWTPs). FCA biotransformation was monitored using a wide range of analytical techniques. These techniques were used to monitor not only FCA disappearance, but also the formation of degradation products, in order to propose the metabolic pathway. FCA was biotransformed to 4-fluorobenzoic acid via the formation of 4-fluoroacetophenone. The removal of FCA up to 200 mg L(-1) followed first order kinetics. The half-lives for removal of FCA from the test solutions supplied with 200 mg L(-1), 100 mg L(-1), and 50 mg L(-1) were 53, 18, and 5 hours respectively.

Aerobiosis↗
PubMed1998

Determination of pollutant diffusion coefficients in naturally formed biofilms using a single tube extractive membrane bioreactor.

A novel technique has been used to determine the effective diffusion coefficients for 1,1,2-trichloroethane (TCE), a nonreacting tracer, in biofilms growing on the external surface of a silicone rubber membrane tube during degradation of 1,2-dichloroethane (DCE) by Xanthobacter autotrophicus GJ10 and monochlorobenzene (MCB) by Pseudomonas JS150. Experiments were carried out in a single tube extractive membrane bioreactor (STEMB), whose configuration makes it possible to measure the transmembrane flux of substrates. A video imaging technique (VIT) was employed for in situ biofilm thickness measurement and recording. Diffusion coefficients of TCE in the biofilms and TCE mass transfer coefficients in the liquid films adjacent to the biofilms were determined simultaneously using a resistances-in-series diffusion model. It was found that the flux and overall mass transfer coefficient of TCE decrease with increasing biofilm thickness, showing the importance of biofilm diffusion on the mass transfer process. Similar fluxes were observed for the nonreacting tracer (TCE) and the reactive substrates (MCB or DCE), suggesting that membrane-attached biofilm systems can be rate controlled primarily by substrate diffusion. The TCE diffusion coefficient in the JS150 biofilm appeared to be dependent on biofilm thickness, decreasing markedly for biofilm thicknesses of >1 mm. The values of the TCE diffusion coefficients in the JS150 biofilms <1-mm thick are approximately twice those in water and fall to around 30% of the water value for biofilms >1-mm thick. The TCE diffusion coefficients in the GJ10 biofilms were apparently constant at about the water value. The change in the diffusion coefficient for the JS150 biofilms is attributed to the influence of eddy diffusion and convective flow on transport in the thinner (<1-mm thick) biofilms.

Biodegradation, Environmental↗
PubMed1995

Soft tissue swelling with fractures: abuse versus nonintentional.

The objectives were to 1) define the amount of postfracture swelling at presentation in long bone fractures, and 2) to study the relationship between suspected abuse and/or neglect (A/N) and degree of postfracture swelling at presentation. This was a prospective study of 37 patients less than 11 years of age presenting with long bone fractures to the emergency department (ED) of the Children's Hospital of Michigan between August 1992 and December 1992. Data were recorded at the time of the ED visit and from medical records which were reviewed four to six months later. Of the patients enrolled in the study, eight were categorized as A/N and 29 as nonintentional. There was no difference in reported injury age between the two groups (15.5 +/- 24.5 hours vs 14.0 +/- 17.7, P = 0.8). At presentation the mean increase in circumference from post-fracture swelling was 9.6 +/- 7.1%, using the uninjured extremity as the control. The abuse group had a lesser increase in circumference compared to the nonintentional group, even after adjusting for injury age (3.8 +/- 3.6% vs 11.2 +/- 7.0%, P < 0.006). We concluded that patients with long bone fractures had a mean swelling of 9.6 +/- 7.1% at presentation. Injuries induced by A/N present with less swelling than similar injuries sustained nonintentionally, and we speculate that this difference indicates that the history and/or time of injury may not be reliable.

Acute Disease↗
PubMed1994

Pediatric emergency department walk-outs.

The objectives of this study were to determine reasons for leaving a pediatric emergency department before physician evaluation, any adverse outcomes of those leaving, and to assess whether the presence of an ombudsman altered the pattern. This was a prospective follow-up study of all patients who left the pediatric emergency department of the Children's Hospital of Michigan before physician evaluation between October 24, 1991 and January 30, 1992. Information was obtained from medical records and a telephone questionnaire with the parent or guardian one week later. A control group of patients (n = 150) evaluated in the same period were randomly selected for comparison and matched for triage acuity score, shift, and weekday/weekend visit. Five hundred and twelve patients left during this period. Contact was made with 82% (419). Forty-three percent of patients left only because of a long wait, and an additional 19% included a long wait as one of the reasons for leaving. There was a significantly longer waiting time for walk-outs compared with controls (188 +/- 76.4 vs 93.6 +/- 64.9 minutes, P < 0.0001). Of the 419 patients followed, 256 (61%) were seen by a physician within seven days, and seven (1.7%) were hospitalized. Three hundred one (72%) were reported to be well; 108 (26%) were better. No deaths occurred. Hospitalization rates were significantly lower for patients who left compared with patients who stayed over the same period of time (7/419 vs 1931/16,990, P < 0.0001). The presence of an ombudsman was associated with an increase in walk-outs.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗
PubMedDate not supplied

[Emotional intelligence: testing the future nursing].

This study traces the nursing students' profile in order to have a prospective professional vision on the emotional intelligence of these workers. Considering that, nowadays, emotional intelligence is a basic requirement for any kind of profession, this research analysed patterns of cognitive, behavioral and emotional skills among the nursing workers. This is a descriptive exploratory study, accomplished in a public institution in the city of Fortaleza-CE, with 138 students enrolled in the first term of 1999. For this analyses an emotional intelligence questionnaire, available in internet, was applied. The subjects also answered questions related to their behavioral, cognitive and emotional skills. As a result, it was concluded that the majority of the students (78.26%) presented a satisfying level of emotional intelligence and only 16.67% would need improvement. In the classification of the three skills as sufficient, regular and insufficient, the cognitive skill exceeded the other two positively. The research showed that students have the basic characteristics of emotional intelligence. They can be in tune and understanding with patients, and also make themselves understood.

Education, Nursing↗