ABSTRACT
Oil spills are a global concern due to their environmental and economical impact. Various commercial systems have been developed to control these spills, including the use of fibers as sorbents. This research investigates the use of various vegetable fibers, namely mixed leaves residues, mixed sawdust, sisal (Agave sisalana), coir fiber (Cocos nucifera), sponge-gourd (Luffa cylindrica) and silk-floss as sorbent materials of crude oil. Sorption tests with crude oil were conducted in deionized and marine water media, with and without agitation. Water uptake by the fibers was investigated by tests in dry conditions and distillation of the impregnated sorbent. The silk-floss fiber showed a very high degree of hydrophobicity and oil sorption capacity of approximately 85goil/g sorbent (in 24hours). Specific gravity measurements and buoyancy tests were also used to evaluate the suitability of these fibers for the intended application.
Subject(s)
Cellulose/chemistry , Disasters , Lignin/analogs & derivatives , Petroleum , Plant Components, Aerial/chemistry , Water Pollutants, Chemical , Water Pollution, Chemical/prevention & control , Absorption , Agave , Lignin/chemistry , LuffaABSTRACT
In a retrospective review of laboratory records at the Department of Mycology, National Institute of Microbiology "Dr. Carlos G. Malbrán", during the period June 1989-July 1991, 1225 putatively immunocompetent cases of superficial mycoses were identified. Ninety five percent of these patients were adults and 5% children. Among the total cases, dermatomycoses were caused, 67.6% by dermatophytes, 25.9% by yeasts, 5.9% by Malassezia furfur. and 0.5% by other fungi, as proven by the isolation of the etiological agents. (Figure 1, Table 2). Among the dermatophytes Trichophyton rubrum and Trichophyton mentagrophytes greatly predominated accounting for 66.6% and 20.0% of the isolates, respectively, whereas Microsporum canis (8.0%). Epidermophyton floccosum (5.1%) and Microsporum gypseum (0.3%) were found with less frequency (Figure 2). Nails (47%) were the most common source of isolates in adults, followed by feet (28%), smooth skin (15%), groin (5%) and hands (2%) (Table 1). Regarding the relative efficiency of the diagnostic methods, the analyses of laboratory results evidenced that, 98% of the cases with clinical findings compatible with mycoses and 76% of the cases with positive cultures (Table 1) were identified by microscopic observation.
Subject(s)
Dermatomycoses/epidemiology , Dermatomycoses/microbiology , Adult , Child , Female , Humans , Incidence , Male , Retrospective StudiesABSTRACT
In a retrospective review of laboratory records at the Department of Mycology, National Institute of Microbiology [quot ]Dr. Carlos G. Malbrán[quot ], during the period June 1989-July 1991, 1225 putatively immunocompetent cases of superficial mycoses were identified. Ninety five percent of these patients were adults and 5
children. Among the total cases, dermatomycoses were caused, 67.6
by Malassezia furfur. and 0.5
by other fungi, as proven by the isolation of the etiological agents. (Figure 1, Table 2). Among the dermatophytes Trichophyton rubrum and Trichophyton mentagrophytes greatly predominated accounting for 66.6
of the isolates, respectively, whereas Microsporum canis (8.0
) and Microsporum gypseum (0.3
) were found with less frequency (Figure 2). Nails (47
) were the most common source of isolates in adults, followed by feet (28
) and hands (2
) (Table 1). Regarding the relative efficiency of the diagnostic methods, the analyses of laboratory results evidenced that, 98
of the cases with clinical findings compatible with mycoses and 76
of the cases with positive cultures (Table 1) were identified by microscopic observation.