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Arturo Acero - One of the best experts on this subject based on the ideXlab platform.
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estructura de un ensamblaje ictico asociado a fondos duros en el caribe colombiano empleando la tecnica del censo visual estacionario cve
Actualidades Biologicas, 2004Co-Authors: Marcela Grijalbabendeck, Edward Castanedamoya, Arturo AceroAbstract:Entre agosto y noviembre de 1995 se caracterizo la estructura de un ensamblaje de peces asociado a fondos duros en el Morrito de Gaira, Caribe colombiano, mediante la tecnica del censo visual estacionario (CVE). Se registraron 109 especies pertenecientes a 63 generos y 34 familias. Las familias con mayor abundancia de individuos fueron Pomacentridae, Holocentridae y Gobiidae, mientras que Serranidae, Pomacentridae y Lutjanidae mostraron la mayor riqueza de especies, entre las que se destacaron Chromis multilineata , Myripristis jacobus, Chromis cyanea , Stegastes partitus y Coryphopterus personatus. El indice de diversidad de Shannon-Wiener se calculo en 4,61 ± 0,03 para el area de estudio. Los analisis de clasificacion e inverso mostraron que existen diferencias en la frecuencia y abundancia de las especies censadas entre los sectores muestreados.
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ESTRUCTURA DE UN ENSAMBLAJE ÍCTICO ASOCIADO A FONDOS DUROS EN EL CARIBE COLOMBIANO EMPLEANDO LA TÉCNICA DEL CENSO VISUAL ESTACIONARIO (CVE) STRUCTURE OF A HARD BOTTOM-FISH ASSEMBLAGE IN THE COLOMBIAN CARIBBEAN USING THE STATIONARY VISUAL CENSUS TECHN
2004Co-Authors: Marcela Grijalba-bendeck, Edward Castañeda-moya, Arturo AceroAbstract:Between August and November 1995, the structure of a hard bottom-fish assemblage around Morrito de Gaira, Colombian Caribbean, was characterized using the Stationary Visual Census Technique (SVCT). The families with the highest abundance were Pomacentridae, Holocentridae, and Gobiidae, while the richest families were Serranidae, Pomacentridae, and Lutjanidae. Chromis multilineata, Myripristis jacobus, Chromis cyanea, Stegastes partitus, and Coryphopterus personatus were the most important species. The Shannon-Wiener diversity index was 4.61 ± 0.03 for the study area. The classification and inverse analyses indicated differences in the frequency and abundance of the censused species between sampled sectors.
Jeffrey L Ecke - One of the best experts on this subject based on the ideXlab platform.
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randomized comparison of chromic versus fast absorbing polyglactin 910 for postpartum perineal repair
Obstetrics & Gynecology, 2004Co-Authors: James A Greenberg, Amy Cohe, Ellice Lieberma, Jeffrey L EckeAbstract:OBJECTIVE: We conducted a randomized trial to evaluate the healing characteristics of chromic versus fast-absorbing polyglactin 910. METHODS: Laboring women were randomly assigned to chromic or fast-absorbing polyglactin for perineal repairs. Subjects were evaluated at 24-48 hours, 10-14 days, and 6-8 weeks to assess perineal and uterine pain, analgesic use, presence of residual suture, and wound dehiscence. RESULTS: Between April 2002 and January 2003, 1,361 subjects were randomly assigned. Two thirds of women in each group (459 fast-absorbing polyglactin and 449 chromic) required sutures for perineal repairs. Women were evaluated according to randomization assignment. Overall, 794 (87%) of subjects received the appropriate allocated suture to repair a perineal laceration (399 of 459, 86.9% fast-absorbing polyglactin 910; 395 of 449, 88% chromic catgut). At 24-48 hours, there was a statistically significant reduction in uterine cramping pain (25% versus 34%; P =.006) in subjects randomly assigned to fast-absorbing polyglactin. At 10-14 days, there were no statistically significant differences between the groups. At 6-8 weeks there was, again, a statistically significant reduction in uterine cramping pain (1% versus 4%; P =.017) and a statistically significant decrease in analgesic use (5% versus 10%; P =.048) in subjects randomly assigned to fast-absorbing polyglactin. Finally, at 6-8 weeks postpartum there was no difference in residual suture (2 of 175 versus 2 of 134; P =.802) or wound breakdowns (4 of 175 versus 3 of 134; P =.959) for fast-absorbing polyglactin 910 and chromic catgut, respectively. CONCLUSION: Our data suggest that fast-absorbing polyglactin 910 and chromic elicit similar postpartum perineal discomfort. In contrast to previous studies evaluating standard polyglactin, our trial demonstrated that fast-absorbing polyglactin rarely requires late removal and has a similar wound breakdown profile as compared with chromic. LEVEL OF EVIDENCE: I
Muxing Guo - One of the best experts on this subject based on the ideXlab platform.
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Degradation mechanisms of alumina-chromia refractories for secondary copper smelter linings
Corrosion Science, 2018Co-Authors: Liugang Chen, Annelies Malfliet, Jef Vleugels, Bart Blanpain, Muxing GuoAbstract:Abstract To assess the viability of an alumina-chromia refractory alternative for secondary copper smelters, the degradation behavior of alumina-chromia refractories in a secondary copper smelting slag and a Cu-CuxO mixture was studied via lab scale refractory finger testing. Microstructural characterization of the worn refractory samples resulted in a comprehensive understanding of the corrosion and penetration resistance and a comparison with the degradation of magnesia-chromite refractories. Alumina grains in the refractory are preferentially corroded by the slag. The alumina-chromia refractory exhibits superior infiltration resistance to the slag and the Cu-CuxO mixture compared to magnesia-chromite refractories.
Vera Dos Santos Domingues - One of the best experts on this subject based on the ideXlab platform.
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historical population dynamics and demography of the eastern atlantic pomacentrid Chromis limbata valenciennes 1833
Molecular Phylogenetics and Evolution, 2006Co-Authors: Vera Dos Santos Domingues, Ricardo S Santos, Alberto Brito, Vitor Carvalho AlmadaAbstract:Recent studies have focused on the relationship between the marine fauna of the eastern Atlantic and the Mediterranean Sea, but within the Atlantic, little is known about genetic relationships between populations of the Macaronesian islands. In this study, we tested whether the paleo-climatology and paleo-oceanography of the region could predict the genetic relationships among three eastern Atlantic populations (Azores, Madeira, and Canaries) of a damselWsh, Chromis limbata, and compared our results with its Mediterranean and adjacent Atlantic sister species, Chromis Chromis. We combined phylogeographic and coalescent approaches using the fast evolving mitochondrial control region gene. No population structure was found for the three archipelagos. The coalescence time estimated for C. limbata (0.857–1.17 Mya) was much greater than that estimated for C. Chromis. We propose that this diVerence reXects diVerences in glaciating extents in the Northeastern Atlantic and the Mediterranean. Diversity indexes (Hd and genetic distances) together with historical demographic parameters of C. limbata ( and g) revealed a more stable population history when compared to C. Chromis. Our results suggest that the Macaronesian populations of C. limbata have probably been less aVected by the last glaciation than the Mediterranean populations of C. Chromis. Migration across the three archipelagos was estimated and a prevailing northwest trend was detected. This result supports the idea of a colonization of the Azores by warm water Wsh from Madeira or the westernmost Canary islands which acted as major glacial refugia for the tropical and subtropical marine fauna during the glaciations.
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historical colonization and demography of the mediterranean damselfish Chromis Chromis
Molecular Ecology, 2005Co-Authors: Vera Dos Santos Domingues, Vitor Carvalho Almada, Giuseppe Bucciarelli, Giacomo BernardiAbstract:The desiccation of the Mediterranean Sea during the Messinian Salinity Crisis 6.0–5.3 million years ago (Ma), caused a major extinction of the marine ichthyofauna of the Mediterranean. This was followed by an abrupt replenishment of the Mediterranean from the Atlantic after the opening of the Strait of Gibraltar. In this study, we combined demographic and phylogeographic approaches using mitochondrial and nuclear DNA markers to test the alternative hypotheses of where (Atlantic or Mediterranean) and when (before or after the Messinian Salinity Crisis) speciation occurred in the Mediterranean damselfish, Chromis Chromis . The closely related geminate transisthmian pair Chromis multilineata and Chromis atrilobata was used as a way of obtaining an internally calibrated molecular clock. We estimated C . Chromis speciation timing both by determining the time of divergence between C . Chromis and its Atlantic sister species Chromis limbata (0.93–3.26 Ma depending on the molecular marker used, e.g. 1.23–1.39 Ma for the control region), and by determining the time of coalescence for C . Chromis based on mitochondrial control region sequences (0.14–0.21 Ma). The time of speciation of C . Chromis was always posterior to the replenishment of the Mediterranean basin, after the Messinian Salinity Crisis. Within the Mediterranean, C . Chromis population structure and demographic characteristics revealed a genetic break at the Peloponnese, Greece, with directional and eastbound gene flow between western and eastern groups. The eastern group was found to be more recent and with a faster growing population (coalescent time = 0.09–0.13 Ma, growth = 485.3) than the western group (coalescent time = 0.13–0.20 Ma, growth = 325.6). Our data thus suggested a western origin of C . Chromis , most likely within the Mediterranean. Low sea water levels during the glacial periods, the hydrographic regime of the Mediterranean and dispersal restriction during the short pelagic larval phase of C . Chromis (18–19 days) have probably played an important role in C . Chromis historical colonization.
Vitor Carvalho Almada - One of the best experts on this subject based on the ideXlab platform.
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historical population dynamics and demography of the eastern atlantic pomacentrid Chromis limbata valenciennes 1833
Molecular Phylogenetics and Evolution, 2006Co-Authors: Vera Dos Santos Domingues, Ricardo S Santos, Alberto Brito, Vitor Carvalho AlmadaAbstract:Recent studies have focused on the relationship between the marine fauna of the eastern Atlantic and the Mediterranean Sea, but within the Atlantic, little is known about genetic relationships between populations of the Macaronesian islands. In this study, we tested whether the paleo-climatology and paleo-oceanography of the region could predict the genetic relationships among three eastern Atlantic populations (Azores, Madeira, and Canaries) of a damselWsh, Chromis limbata, and compared our results with its Mediterranean and adjacent Atlantic sister species, Chromis Chromis. We combined phylogeographic and coalescent approaches using the fast evolving mitochondrial control region gene. No population structure was found for the three archipelagos. The coalescence time estimated for C. limbata (0.857–1.17 Mya) was much greater than that estimated for C. Chromis. We propose that this diVerence reXects diVerences in glaciating extents in the Northeastern Atlantic and the Mediterranean. Diversity indexes (Hd and genetic distances) together with historical demographic parameters of C. limbata ( and g) revealed a more stable population history when compared to C. Chromis. Our results suggest that the Macaronesian populations of C. limbata have probably been less aVected by the last glaciation than the Mediterranean populations of C. Chromis. Migration across the three archipelagos was estimated and a prevailing northwest trend was detected. This result supports the idea of a colonization of the Azores by warm water Wsh from Madeira or the westernmost Canary islands which acted as major glacial refugia for the tropical and subtropical marine fauna during the glaciations.
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historical colonization and demography of the mediterranean damselfish Chromis Chromis
Molecular Ecology, 2005Co-Authors: Vera Dos Santos Domingues, Vitor Carvalho Almada, Giuseppe Bucciarelli, Giacomo BernardiAbstract:The desiccation of the Mediterranean Sea during the Messinian Salinity Crisis 6.0–5.3 million years ago (Ma), caused a major extinction of the marine ichthyofauna of the Mediterranean. This was followed by an abrupt replenishment of the Mediterranean from the Atlantic after the opening of the Strait of Gibraltar. In this study, we combined demographic and phylogeographic approaches using mitochondrial and nuclear DNA markers to test the alternative hypotheses of where (Atlantic or Mediterranean) and when (before or after the Messinian Salinity Crisis) speciation occurred in the Mediterranean damselfish, Chromis Chromis . The closely related geminate transisthmian pair Chromis multilineata and Chromis atrilobata was used as a way of obtaining an internally calibrated molecular clock. We estimated C . Chromis speciation timing both by determining the time of divergence between C . Chromis and its Atlantic sister species Chromis limbata (0.93–3.26 Ma depending on the molecular marker used, e.g. 1.23–1.39 Ma for the control region), and by determining the time of coalescence for C . Chromis based on mitochondrial control region sequences (0.14–0.21 Ma). The time of speciation of C . Chromis was always posterior to the replenishment of the Mediterranean basin, after the Messinian Salinity Crisis. Within the Mediterranean, C . Chromis population structure and demographic characteristics revealed a genetic break at the Peloponnese, Greece, with directional and eastbound gene flow between western and eastern groups. The eastern group was found to be more recent and with a faster growing population (coalescent time = 0.09–0.13 Ma, growth = 485.3) than the western group (coalescent time = 0.13–0.20 Ma, growth = 325.6). Our data thus suggested a western origin of C . Chromis , most likely within the Mediterranean. Low sea water levels during the glacial periods, the hydrographic regime of the Mediterranean and dispersal restriction during the short pelagic larval phase of C . Chromis (18–19 days) have probably played an important role in C . Chromis historical colonization.