0000000000049456
AUTHOR
Gabriella La Manna
showing 6 related works from this author
Viscosimetric investigation of the interaction between sodium dodecylsulfate micelles and a polymer drug carrier
1993
Abstract The viscosities of aqueous sodium dodecyl sulfate solutions with and without α,β-poly( N -hydroxyethyl)- dl -aspartamide (PHEA), at 15, 25 and 35°C are reported. The viscosities of SDS and of PHEA aqueous solutions are discussed in terms of the parameter D [D = ( η η 0 − 1)/φ] describing the non-ideal behavior of SDS micelles and of PHEA macromolecules. The viscosities of SDS plus PHEA aqueous solutions, discussed in terms of the parameter F [ F = η rel ( PHEA ) + η rel ( SDS ) − η rel ( SDS + PHEA )] M , demonstrate the occurrence of interactions between SDS micelles and the PHEA macromolecule. Both D and F are scarcely influenced by temperature variation.
A False Sense of Protection: Recreational Uses and Illegal Behavior in a Mediterranean Marine Protected Area and Implications for Management.
2019
Over the last 35 years, at both the European and the Italian level, great efforts have been made to increase the number of Marine Protected Areas (MPAs): they are considered an effective tool for protecting oceans and biodiversity. In recent years, MPAs have become more than simply tools to improve marine conservation. In fact, their management agencies are actively involved in the sustainable development of nearby communities through the promotion of recreational activities (boating, snorkeling, diving). Even if the recreational uses of the marine environment are generally considered benign, they can potentially be highly detrimental for species and their habitats. As a result, these activ…
Dielectric Behavior of Aqueous Solutions of α,β-Poly(aspartyl hydrazide) and α,β-Poly(N-hydroxyethyl aspartamide): An Investigation of the Structural…
1994
The dielectric properties of aqueous solutions of α,β-poly(aspartyl hydrazide) (PAHy) and of α,β-poly( N-hydroxyethyl aspartamide) (PHEA) were measured at 25 ° C in the frequency range of 100 MHz to 15 GHz using a time domain reflection method (TDR). Single time relaxation processes were found at 2 GHz and 15 GHz, respectively. The low frequency dispersion was inter preted in terms of the dynamics of polymeric segments based on the dielectric relaxation strength and the relaxation time. The high frequency process which is attributed to the rotational relaxation of water, indicated that water mole cules surrounding the polymeric backbone and in the pure state have a similar rotational behav…
Whistle variation in Mediterranean common bottlenose dolphin: The role of geographical, anthropogenic, social, and behavioral factors.
2020
Abstract The studies on the variation of acoustic communication in different species have provided insight that genetics, geographic isolation, and adaptation to ecological and social conditions play important roles in the variability of acoustic signals. The dolphin whistles are communication signals that can vary significantly among and within populations. Although it is known that they are influenced by different environmental and social variables, the factors influencing the variation between populations have received scant attention. In the present study, we investigated the factors associated with the acoustic variability in the whistles of common bottlenose dolphin (Tursiops truncatu…
Assessing geographical variation on whistle acoustic structure of three Mediterranean populations of common bottlenose dolphin (Tursiops truncatus)
2017
Whistles are acoustic signals produced particularly during social interactions. Here, we compare whistles by bottlenose dolphins from three Mediterranean areas (Croatia, Sicily and Sardinia) to investigate the presence of acoustic divergence and to discuss the possible causes of variability. Whistle parameters differ significantly between populations, but PCA highlights that the majority of variability is due to a limited number of frequency parameters. Cluster and DFA show that the Croatian population is acoustically divergent from the western populations of Sicily and Sardinia. This divergence could be consistent with geographical isolation, and a possible genetic differentiation between …
Common Bottlenose Dolphin Protection and Sustainable Boating: Species Distribution Modeling for Effective Coastal Planning
2020
Indicators for preserving marine biodiversity include knowledge of how the spatial distribution and critical habitats of species overlap with human activities and impacts. Such indicators are key tools for marine spatial planning, a process that identifies and resolves conflicts between human uses and the conservation of marine environments. The common bottlenose dolphin in the Mediterranean Sea is considered a vulnerable species by the IUCN Red List and a priority species of the EU Habitat Directive. Here, we estimated spatio-temporal patterns of the species occurrence in the area around one Marine Protected Area (MPA) and two Sites of Community Importance (SCI) of the North western Sardin…