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1.
Sci Total Environ ; 808: 151886, 2022 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-34822900

RESUMEN

Fish are some of the most threatened vertebrates in the world due to their often-sensitive response to environmental changes. Major land-use changes in the European Alps have direct and indirect impacts on fish communities, and these impacts are expected to increase in the future. Therefore, the identification of factors that are associated with the distribution of fish communities is of great importance to develop guidelines for management, precautions and sustainable use of running waters. In this study, the relationship of various factors - landscape structure and land use, topography, morphology, hydrology, physical and chemical water characteristics, hormonally active substances, pesticides, food availability, fisheries and piscivores birds - with fish assemblages are analysed. Field data from 81 stream sections from 2001 metres above sea level (m.a.s.l.) down to 219 m.a.s.l. are used in the study. The results reveal that the number of fish species has a strong association with topographic characteristics in the catchment area as well as with landscape configuration. Fish abundance and biomass are associated mostly with land-use type, hydrology, morphology as well as topography. In addition, there are indirect connections between fish abundance and biomass through land-use type, topography, water properties and hydromorphology. The results clearly indicate that not a single factor, but a multitude of factors are associated with the fish communities in the Eastern European Alps.


Asunto(s)
Ecosistema , Peces , Animales , Biomasa , Región Alpina Europea , Explotaciones Pesqueras , Ríos
2.
J Pharm Sci ; 98(6): 2010-26, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19009597

RESUMEN

Five phase-pure modifications of the antipsychotic drug aripiprazole were prepared and characterized by thermal analysis, vibrational spectroscopy and X-ray diffractometry. All modifications can be produced from solvents, form I additionally by heating of form X degrees to approximately 120 degrees C (solid-solid transformation) and form III by crystallization from the melt. Thermodynamic relationships between the polymorphs were evaluated on the basis of thermochemical data and visualized in a semi-schematic energy/temperature diagram. At least six of the ten polymorphic pairs are enantiotropically and two monotropically related. Form X degrees is the thermodynamically stable modification at 20 degrees C, form II is stable in a window from about 62-77 degrees C, and form I above 80 degrees C (high-temperature form). Forms III and IV are triclinic ($P\overline 1$), I and X degrees are monoclinic (P2(1)) and form II orthorhombic (Pna2(1)). Each polymorph exhibits a distinct molecular conformation, and there are two fundamental N-H$\cdots$O hydrogen bond synthons (catemers and dimers). Hirshfeld surface analysis was employed to display differences in intermolecular short contacts. A high kinetic stability was observed for three metastable polymorphs which can be categorized as suitable candidates for the development of solid dosage forms.


Asunto(s)
Antipsicóticos/química , Piperazinas/química , Quinolonas/química , Antipsicóticos/síntesis química , Aripiprazol , Rastreo Diferencial de Calorimetría , Cristalización , Cristalografía por Rayos X , Humanos , Cinética , Conformación Molecular , Piperazinas/síntesis química , Quinolonas/síntesis química , Solventes/química , Espectrofotometría Infrarroja , Espectrometría Raman , Termodinámica
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