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1.
Sci Rep ; 13(1): 17890, 2023 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-37857721

RESUMEN

Mesopelagic fish constitute the most abundant vertebrate group in the marine environment. The current work reports on results of three seasonal acoustic cruises carried out in the Gulf of Corinth, a relatively small, deep, isolated basin located in the Central Mediterranean (Greece) that presents some unique geomorphological and ecological features. The aim of this study was to describe seasonal echo-types and the vertical distribution of the Deep Scattering Layers (DSLs) as well as to relate them with specific species or species groups. Mesopelagic fish dominated the pelagic ecosystem as confirmed by biological sampling with different gears during daytime and nighttime. In total, at least 15 species were caught, belonging to the families Myctophidae, Paralepididae, Sternoptychidae and Stomiidae, while the-elsewhere very abundant-families Gonostomatidae and Phosichthyidae were completely absent. Common echo-types included: (a) shoals and schools formed by the silvery lightfish Maurolicus muelleri, usually located along the shelf break (80-225 m), (b) a non-migrant thin DSL found at 150-280 m throughout the deep parts of the Gulf, dominated by juvenile half-naked hatchetfish Argyropelecus hemigymnus, and (c) one thick, partially migratory DSL at 250-600 m, mainly consisting of myctophids. The echo backscatter characteristics and species composition of the DSLs as well as the length distribution of the populations were found to differ seasonally. Species-specific and size related patterns in the vertical distribution of fish were detected both during daytime and nighttime. Overall, the Gulf of Corinth seems to sustain high densities of mesopelagic fish that constitute the basic food resource for the abundant dolphin populations that inhabit the area.


Asunto(s)
Ecosistema , Peces , Animales , Acústica , Grecia , Estaciones del Año
2.
Environ Sci Pollut Res Int ; 23(13): 12835-66, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27023823

RESUMEN

Present technologies for wastewater treatment do not sufficiently address the increasing pollution situation of receiving water bodies, especially with the growing use of personal care products and pharmaceuticals (PPCP) in the private household and health sector. The relevance of addressing this problem of organic pollutants was taken into account by the Directive 2013/39/EU that introduced (i) the quality evaluation of aquatic compartments, (ii) the polluter pays principle, (iii) the need for innovative and affordable wastewater treatment technologies, and (iv) the identification of pollution causes including a list of principal compounds to be monitored. In addition, a watch list of 10 other substances was recently defined by Decision 2015/495 on March 20, 2015. This list contains, among several recalcitrant chemicals, the painkiller diclofenac and the hormones 17ß-estradiol and 17α-ethinylestradiol. Although some modern approaches for their removal exist, such as advanced oxidation processes (AOPs), retrofitting most wastewater treatment plants with AOPs will not be acceptable as consistent investment at reasonable operational cost. Additionally, by-product and transformation product formation has to be considered. The same is true for membrane-based technologies (nanofiltration, reversed osmosis) despite of the incredible progress that has been made during recent years, because these systems lead to higher operation costs (mainly due to higher energy consumption) so that the majority of communities will not easily accept them. Advanced technologies in wastewater treatment like membrane bioreactors (MBR) that integrate biological degradation of organic matter with membrane filtration have proven a more complete elimination of emerging pollutants in a rather cost- and labor-intensive technology. Still, most of the presently applied methods are incapable of removing critical compounds completely. In this opinion paper, the state of the art of European WWTPs is reflected, and capacities of single methods are described. Furthermore, the need for analytical standards, risk assessment, and economic planning is stressed. The survey results in the conclusion that combinations of different conventional and advanced technologies including biological and plant-based strategies seem to be most promising to solve the burning problem of polluting our environment with hazardous emerging xenobiotics.


Asunto(s)
Analgésicos/análisis , Diclofenaco/análisis , Estradiol/análisis , Etinilestradiol/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Unión Europea , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/análisis
3.
J Fish Biol ; 83(6): 1551-75, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24298951

RESUMEN

Spatial distribution and life history aspects of Pagellus bogaraveo in the eastern Ionian Sea were investigated using the data from 13 different studies carried out in the area from 1983 to 2010. The spatial patterns of the abundance, biomass and mean size showed that the species inhabits the shallow waters of the shelf (<170 m depth) as juveniles up to a certain size (<180 mm total length, LT ), moving to deeper waters of the slope (mainly 400-500 m depth) as adults. The spatial pattern of abundance indicated a continuous distribution of the species in deep waters, with hot-spot areas of high values, whereas in shallow waters distribution was more discontinuous, with higher concentrations of juveniles in estuaries and brackish waters. The study of biological aspects of the species revealed (1) a difference in the increase in mass between males and females, (2) protandrous hermaphroditism, accompanied by the presence of primary females and males that do not change sex, (3) a sex ratio in favour of females >250 mm LT , (4) the presence of hermaphrodites between 200 and 370 mm, (5) a long reproduction period from June to March, (6) a size at first maturity around 300 mm and (7) a diet composition of adults based mainly on fishes, and also on opportunistic behaviour in the food scarce environment of deep waters. The results suggest that the species' distribution and feeding strategies are the most appropriate for the oligotrophic eastern Ionian waters and that these conditions result in smaller sizes of the species in the east Mediterranean Sea compared to the west basin and the east Atlantic Ocean, with implications for the growth and reproductive biology of the species.


Asunto(s)
Distribución Animal , Dorada/fisiología , Animales , Biomasa , Tamaño Corporal , Femenino , Organismos Hermafroditas , Estadios del Ciclo de Vida , Masculino , Océanos y Mares , Razón de Masculinidad
4.
Environ Manage ; 36(4): 610-23, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16222463

RESUMEN

Wastewater treatment facilities in tourist areas, in comparison to other municipal facilities, require specific configurations and additional management actions in order to achieve a reliable and cost-effective treatment. For example, the same facility operates during winter with minimum flows and in summer with peak flows. Moreover, careful effluent management is required to minimize environmental impact and health effects on tourists. In this study, effluent management data, including quantitative and qualitative effluent characteristics, reuse, and economic aspects of the Hersonissos Wastewater Treatment Plant (WTP) in Greece, are discussed. It has been designed to treat both municipal wastewater from the Hersonissos Municipality and septage from the wider area. Analysis of effluent quantitative data showed two flow peaks in the summer period and only one in winter. The WTP was found to provide a reliable level of treatment in terms of biochemical oxygen demand (95.9%), total suspended solids (97.2%), and total nitrogen (87.7%) removal, but increased numbers of fecal coliforms were measured at some peak flow periods, suggesting the need for additional management strategies. Effluent is reused mainly for agricultural irrigation; secondary uses include fire protection and landscape irrigation. Economic analysis showed that for each cubic meter treated, the total annual economic cost for treatment, filtration, and reuse infrastructure was 1.07 euro, 0.05 euro, and 0.08 euro, respectively.


Asunto(s)
Conservación de los Recursos Naturales , Eliminación de Residuos Líquidos/métodos , Abastecimiento de Agua , Conservación de los Recursos Naturales/economía , Análisis Costo-Beneficio , Enterobacteriaceae/aislamiento & purificación , Grecia , Nitrógeno/análisis , Nitrógeno/aislamiento & purificación , Oxígeno/metabolismo , Recreación , Viaje , Contaminación del Agua/prevención & control , Abastecimiento de Agua/economía
5.
Water Sci Technol ; 44(6): 163-72, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11700656

RESUMEN

Technologies to treat wastewater are now well established and are capable of producing almost any degree of purification. The main issue surrounding the selection of a given process lies in deciding which is the most appropriate and applicable technology for the particular social, political and economic environment. This paper concentrates on the development of the municipal wastewater treatment sector in Greece. It examines the deficiencies and problems arising from the implementation of wastewater management policies and makes a number of suggestions and recommendations. The areas considered include, among others, historical development, economic development and pollution control, key issues for wastewater treatment policies and lessons applicable to developing countries. It is hoped that this study will be a valuable source of information for countries embarking on nationwide sanitation projects.


Asunto(s)
Países en Desarrollo , Transferencia de Tecnología , Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos , Grecia , Humanos , Formulación de Políticas , Política , Política Pública , Condiciones Sociales , Eliminación de Residuos Líquidos/economía , Purificación del Agua/economía
6.
Int J Cardiol ; 34(1): 21-31, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1372300

RESUMEN

This paper aims at examining whether there is an association between the circadian patterns of systolic blood pressure, heart rate and the incidence of ventricular ectopic beats, as well as to confirm that reducing the blood pressure by a diuretic may also reduce the ectopic frequency. Thirty-four ambulatory patients with ventricular ectopic beats and a systolic blood pressure of 131.33 +/- 17.46 mmHg had a 24-hour Holter electrocardiographic and blood pressure monitoring following 1 week off any antiarrhythmic and antihypertensive treatment. Then they received for one week a standard diuretic combination (amiloride 5 mg + hydrochlorothiazide 50 mg) at a dose depending on their systolic pressure value and their monitoring was repeated. The mean hourly values of systolic blood pressure, heart rate and ventricular ectopic beats were "normalized", i.e. expressed as (x-x)/SD, taking each patient's 24-hour average as zero and his own standard deviation as the unit of measurement. As a group, there was an independent positive correlation between blood pressure and ectopic beats, while the heart rate was a nonsignificant negative factor for ectopic beats. On an individual level, however, an independent positive significant correlation between blood pressure and ectopic beats was found in only 8 cases, with a negative one in 4 cases. While the blood pressure of the group ranged symmetrically around its daily average value, the corresponding ectopic beat curve was highly asymmetric, with a very high incidence (up to 2.56 +/- 0.52 SD) for a rather short time (only 9.41 +/- 3.56 hours above average) and a low incidence (up to 1.26 +/- 0.49 SD) for the remaining 14.59 hours below average. Sudden rises in ectopic beat (greater than 1 SD/hour) occurred 1 to 6 times per day in each individual, significantly (P less than 0.01) more often (20.31%) with a high (greater than 1 SD) blood pressure than with a low (less than -1 SD) one (8.99%) with intermediate frequencies at intermediate pressures. After treatment with the diuretic, the systolic blood pressure was reduced, the heart rate increased and the ventricular ectopic beat incidence reduced (significant changes). The mean change in systolic pressure in 25 patients with a reduction in ectopy was a significant (P less than 0.01) decrease (-5.21 +/- 8.70 mmHg) while in the remaining 9 cases there was a non significant increase (+1.68 +/- 7.63 mmHg). The heart rate was higher in both subgroups.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Complejos Cardíacos Prematuros/etiología , Ritmo Circadiano , Frecuencia Cardíaca , Ventrículos Cardíacos , Hipertensión/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Amilorida/administración & dosificación , Amilorida/uso terapéutico , Presión Sanguínea , Monitores de Presión Sanguínea , Complejos Cardíacos Prematuros/diagnóstico , Complejos Cardíacos Prematuros/epidemiología , Quimioterapia Combinada , Electrocardiografía Ambulatoria , Femenino , Hemodinámica , Humanos , Hidroclorotiazida/administración & dosificación , Hidroclorotiazida/uso terapéutico , Hipertensión/diagnóstico , Hipertensión/tratamiento farmacológico , Incidencia , Masculino , Persona de Mediana Edad , Sístole
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