Now showing items 21-40 of 36382

    • Impacto do barramento de um rio amazônico sobre os padrões de sincronia de grupos funcionais fitoplanctônicos.

      Campos, Beatriz Melissa (Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais., 2022)
      The degree at which populations are correlated in space is called spatial synchrony and can be affected by interspecific interactions, dispersion, and large-scale environmental factors, i. e. Moran effect. The study of this phenomenon can help understanding the temporal stability of communities and the underlying mechanisms. The influence of damming in a river from the Amazon basin (Santo Antônio do Jari HPP) on the synchrony of the environment and the phytoplankton community was evaluated, both for the total density and for different Reynolds functional groups. Was investigated whether the effects would be similar for the main channel (Jari River), tributaries, and for the total area (Jari + tributaries). The mean synchrony values and the confidence intervals of each abiotic variable, functional group, and the total density were estimated for the total area, Jari River and tributaries. Matrix-based multiple regression were also performed to identify the most important drivers of synchrony of the phytoplankton. Changes in the synchrony patterns were verified after the damming. The temporal dynamics of environmental variables, total density and of some functional groups was more synchronous when considering only the Jari River, than the total area or only tributaries. Environmental synchrony and environmental distance were the main mechanisms behind synchrony for some functional groups.
    • Descrição de sete novas espécies e dois novos gêneros de Physocypria sensu latu (Crustacea, Ostracoda) de planícies de inundação brasileiras.

      Almeida, Nadiny Martins de (Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais., 2022)
      We describe seven new species of Physocypria sensu latu from three of the main Brazilian floodplains: Gen. 1 spec. A gen. et spec. nov. and Gen. 1 spec. B gen. et spec. nov. from the Upper Paraná River floodplain and the South Matogrossense Pantanal, Gen. 2 spec. C gen. et spec. nov., Gen. 1 spec. D gen. et spec. nov. and Gen. 2 spec. E gen. et spec. nov. from the South Matogrossense Pantanal only and Gen. 1 spec. F gen. et spec. nov. and Gen. 1 spec. G gen. et spec. nov. only from the Amazon River floodplain. All new species here described were found in sexual populations. Generally, the new species have a short and suboval carapace, with the left valve overlapping the right valve on all sides, except for the dorsal side in some species. The morphology of hemipenis and prehensile palps, together with the shape of the valves, were most important to distinguish the species. However, several other morphological characters from limb chaetotaxy are discussed, e.g., the absence in all new species of the short accompanying seta of the five natatory setae on antenna; the presence in all new species of a long seta next to the two a-seta on the first thoracopod and the presence/absence or length of specific setae on second and third thoracopod. We discuss the taxonomic position of the seven new species by evaluating the validity of extant genera, especially of Keysercypria Karanovic, 2011, and foreshadow that our seven new species represent two new genera of Cyclocypridinae.
    • Relação entre a complexidade estrutural de macrófitas e os atributos da assembleia de peixes em um reservatório Neotropical.

      Dal Vesco, Bianca Morelatto (Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais., 2022)
      Habitat complexity is one of the main factors determining biological diversity and its assessment is a challenge that involves several variables. Submerged macrophytes are responsible for changes in habitat complexity and may enhance habitat conditions for different species. These plants usually colonize natural and artificial lentic environments, such as reservoirs, which have abiotic characteristics favorable to their establishment. The construction of the Itaipu Dam and the filling of the reservoir favored the establishment of macrophytes due to changes in flow dynamics. Therefore, the aim of this work was to evaluate whether habitat complexity, provided by macrophytes, is associated with changes in fish assemblage attributes (abundance, richness, and evenness) and composition. Linear regression models were applied to test the relationship between abundance, richness, and evenness with habitat complexity (expressed as macrophyte density - g/m²). In addition, Principal Coordinates Analysis (PCoA) and Spearman correlations were used to assess changes in the composition of fish assemblages according to macrophytes density. The results indicate a direct relationship between habitat complexity and fish assemblage attributes as well as associations between macrophyte density and fish assemblage composition, improving the knowledge about species preference for different levels of complexity. Thus, it is important to consider the behavior of species known to cause economic and ecological issues for future management and conservation efforts.
    • Alteração da concentração de nutrientes causada por P. ambrosettii afeta relação entre macrófita invasora H. verticillata e nativa E. najas: uma abordagem experimental.

      Reinas, Gabriela Cassia Zanon (Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais., 2022)
      Non native species can negatively affect the invaded environment. Often, these species have biological characteristics that benefit other non natives and facilitate their invasion, so knowing the facilitation mechanisms between invaders are useful to mitigate their damage to the ecosystem. Thus, in this study we tested the hypothesis that Pterygoplichthys ambrosettii, a non native catfish, has habits that can alter nutrient concentrations (phosphorus and nitrogen) in the water column, and positively affect the growth of an invasive macrophyte species in detriment of a native one, characterizing ecological facilitation among invasive species. Therefore, an experiment was conducted with six treatments and four replicas, using the invasive macrophyte Hydrilla verticillata and the native Egeria najas, in the presence and absence of P. ambrosettii, all with occurrence recorded in the upper Paraná River floodplain. The results showed that the treatments with P. ambrosettii had a lower amount of dissolved oxygen, higher electrical conductivity, higher concentration of chlorophyll-a, total phosphorus (TP) and inorganic nitrogen (NI). Macrophyte biomass was significantly higher in monoculture treatments with fish, with this effect being more intense for H. verticillata. When in the same treatment, in the absence of P. ambrosettii, H. verticillata showed greater biomass than E. najas, but with the fish presence, the macrophyte species did not differ in their biomass, indicating that the high concentration of nutrients makes the coexistence of these macrophytes possible. The results found will be useful for future actions to manage invasive species, especially in habitats where they co-occur.
    • Mudanças globais: avaliando as interações entre CO2, eutrofização e espécies não nativas em ecossistemas aquáticos continentais.

      Hein, Gabriela Sponchiado (Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais., 2022)
      Ecosystems respond to the direct, indirect and synergistic effects of global changes caused by human activity. The understanding of the impacts of these changes and especially of the interaction between the impacts is still limited, especially for aquatic environments, because the interaction between them is rarely considered in environmental studies and assessments. We conducted a systematic literature review on the combination of the factors (i) increase of CO2, (ii) eutrophication and (iii) non-native species to verify how these factors have been considered in the context of climate change in freshwater ecosystems studies. Through the Web of Science database, we searched for articles published in English, up to 2020. Following the PRISMA protocol, 62 articles were analyzed. Only 8% of them addressed the combination of the three factors, among them, eutrophication was the most evaluated global change. Still, the studies do not seem to be looking for answers in a broad way and covering several ecological aspects, since they are concentrated in specific regions such as the Netherlands and United States (44%). Studies most focus on one type of environment, the lentic; use organisms from the base of the food-web; apply the experimental approach; evaluate one organizational level (community) and one response variable (biomass). We identified that the effect of the combination of factors is rarely classified with the terms synergistic and antagonist, even when the authors find these patterns. Our main findings reveal that little attention has been given to the combination of factors in freshwater ecosystems. We also find that when interactions are considered, non-native species tend to be favored and algal blooms intensified (74%). Considering that one of the major challenges is to understand how the interaction between global change factors will affect ecosystems, the combinations of factors still need to be prioritized in studies of aquatic ecosystems.
    • DNA barcoding de Platanichthys platana (Regan, 1917) (Clupeiformes, Clupeidae) de diferentes bacias hidrográficas.

      Ramos, Laura Ivana (Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais., 2022)
      South America has fish endemic to continental fresh waters, but derived from clades predominantly and ancestrally distributed in marine environments, such as Platanichthys platana. This species is considered the smallest sardine of the Clupeidae with its type locality in the La Plata river. In 2007, there were the first records of P. platana in the upper Paraná river basin and in 2012 in the upper Paraná river floodplain. The variation in the length of specimens from this basin generated curiosity about their identity and origin of introduction. Sequences from the COI region of the specimens were used for genetic distance calculations, construction of gene trees and haplotype networks. The results obtained indicate that all analyzed specimens belong to P. platana. Eight haplotypes were found, some exclusive to the coastal basins of Santa Catarina, Rio Grande do Sul and Negro river basin. The basins of the La Plata river, the Lago and the upper Paraná river floodplain shared different haplotypes. The phylogeographic pattern presented in this study can be justified by the presence of populations of P. platana in the same paleoarea, before the geological process that configured the current architectures of the observed basins, by vicariance. During the Mesozoic and Cenozoic several vicarious events occurred between the coastal watersheds of Brazil that can be attributed to marine regressions and transgressions by continental lands. It is also assumed that specimens from the upper Paraná river floodplain were introduced to the region from Argentine regions.
    • Filogeografia como escopo para explorar a invasão em Ludwigia (Onagraceae) de ambientes não nativos.

      Silva, Adrian Cesar da (Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais., 2022)
      Ludwigia has some invasive macrophyte species that have not yet been explored under the scope of phylogeography, a promising area to understand the ecology of invasions using barcode molecular markers sensitive to intraspecific variations. Thus, it was theorized that barcode markers used in invasive species of Ludwigia occurring in non-native regions would be phylogeographically informative. Sequences of the molecular markers trnH-psbA, rbcL, matK and phyC from invasive populations of L. peploides and L. grandiflora were used as they are the only ones available in Genbank. A gene tree was generated by the Neighborn-Joining method and a haplotypic network by the Median-Joining method for each species. The trnH-psbA marker was the only phylogeographically informative marker for detecting intraspecific variations in the analyzed taxa. Three haplotypes were detected for L. grandiflora and two haplotypes for L. peploides. Three geographically distinct founder populations of L. grandiflora were introduced in Europe, with Hg1 shared with the US population, while L. peploides has a founder population in Europe and another in the US. The long history of the introduction of these species in Europe and the limited geographic scope of molecular sampling demonstrate that these data are underestimated. A search in the Web of Science database exposed a paucity of molecular data for invasive species of Ludwigia, highlighting the contribution of the results to the information on these haplotypic relationships in the context of invasive biology. Therefore, the detection of haplotypic diversity of invasive species of Ludwigia proved to be promising when investigated by the phylogeographic scope, supporting a better understanding of the management and ecology of these haplotypes in non-native areas.
    • Caracterização molecular de digenéticos parasitas de gastrópodes (Mollusca) do baixo rio Ivaí, Paraná, Brasil.

      Passere, Mayara Destro (Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais., 2022)
      Thiarids are pantropical gastropods endemic to South America and are found in lentic and lotic freshwater environments. These gastropods act as intermediate hosts for several species of digeneans. However, it is important to consider that there are difficulties for a correct identification of these digeneans in certain stages of the life cycle since the larvae have a reduced size and few morphological characteristics for diagnosis. In this way, techniques based on molecular markers become an extremely important tool, combining the use of ribosomal and mitochondrial regions. Considering that there are no records in the literature of studies involving parasites and gastropods as intermediate hosts in the Ivaí River, this study is the first regarding these relationships. Seventy-six specimens of gastropods were collected. Of these, 21 were parasitized. As for the parasites, 16 different morphotypes were found. The gastropod DNA was amplified using the COI marker. The gastropods showed genetic similarity with Aylacostoma chloroticum with different percentages of identity. As for the parasites, COI and 28S markers were used for DNA amplification. Four different taxa were characterized with both markers. With the mitochondrial marker it was possible to confirm only one genus among the digeneans found. However, the 28S ribosomal marker proved to be more effective for the identification of Ivaí River parasites, showing higher similarity values in relation to sequences available in the databases and lower values of genetic distance. In this way, it was possible to confirm the classification of the morphotypes into two distinct genera.
    • Evaluation of maximum catch limits and closure areas in the Western Mediterranean (STECF-22-01).

      Pinto, C; Bastardie, F; Bitetto, I; Borges, L; Certain, G; Gourguet, S; Grati, F; Kupschus, s; Leutha, S; Mannini, A; et al. (Publications Office of the European UnionLuxembourg, 2022)
      Commission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee for Fisheries, C(2016) 1084, OJ C 74, 26.2.2016, p. 4–10. The Commission may consult the group on any matter relating to marine and fisheries biology, fishing gear technology, fisheries economics, fisheries governance, ecosystem effects of fisheries, aquaculture or similar disciplines. This report is the eighth of a suite of STECF EWG reports dedicated to the evaluation of the implementation of the Western Mediterranean Sea Multi-Annual management Plan (hereafter, MAP), following EWG reports 18-09, 18-13, 19-01, 19-14, 20-13, 21-01 and 21-13. The group was requested to implement mixed fisheries bio-economic models to run a number of scenarios up to 2025 with varying parameters and up to 2030 with fixed parameters, to evaluate existing closure areas implemented since 2020 and 2022, maximum catch limits (MCLs) implemented since 2022 and draft a mixed fisheries advice. For all mixed fisheries models applied during the EWG, the data from the DCF official data calls and from the western Mediterranean stock assessments, were the same as the ones used during STECF EWG 21-13, as there were no updates since 2021. The non-spatially explicit mixed fisheries models, IAM (for EMU 1) and BEMTOOL (for EMU 2), focused on the scenarios evaluating MCLs on ARA, ARS and HKE. Reference MCLs for ARA and ARS where obtained from the Regulation EU 2022/110 and from STECF EWG 21-11, while for HKE were obtained solely from EWG 21-11. IAM was updated to differentiate between a coastal and a deep-water trawling within the Spanish fleet segments, as France does not have a deep-water fishery at present. As the model timescale has a yearly resolution, it was not possible to estimate the effect of a monthly MCL. The scenarios considered had a MCL for HKE, one for ARA, and one for both HKE and ARA. These scenarios were run for a decreasing MCL through time (forward scenario: aims at reaching catch at Fmsy by 2025) and an increasing MCL through time (inverse scenario: starting value is catch at Fmsy) accounting for the distribution of stocks by GSA, for a total of 10 scenarios alternative to the baseline. None of the scenarios allowed reaching Fmsy for all six species targeted by the MAP, except when applying a MCL on both ARA and HKE, simultaneously. The results for the HKE stock should be taken with caution as the MCL was applied only to trawlers in these scenarios, but this species can generally be targeted also by longliners and gillnetters. The economic consequences of scenarios accounting for a MCL on HKE, or both ARA and HKE, lead to a massive drop of GVA for the Spanish and French trawling fleets, while economic advantages are observed for longliners and gillnetters. BEMTOOL was updated and refined to consider the different types of fishing activity exerted by each fleet segment at metier level. The model timescale is set at a monthly resolution, so it was possible to run scenarios accounting for a monthly MCL (monthly flexibility was not considered). Only scenarios accounting for a MCL either for ARA or ARS where run, but never in combination (ARA+ARS), nor considering a MCL on HKE, for a total of eight scenarios: forward scenario, inverse scenario, monthly forward scenario, monthly inverse scenario, once with an MCL on ARA and once with an MCL on ARS. Implementing a MCL on the deep-water fisheries suggested an improvement for all stocks except for HKE. ARA and ARS would improve thanks to the control of the MCL, while MUT, DPS and NEP would stay within the upper and lower limits of Fmsy, despite the reallocation of fishing effort from deep to coastal fisheries. The implementation of a reverse MCL did not show a recovery of the stocks. Moreover, a MCL split by month seems to have a lower impact on the catches of ARA and ARS in the short term. The GVA shows an increase for the passive gears fleets (i.e., gillnetters and longliners) and a strong decrease for all trawling fleets in the first two years, with a stable trend over the following years. The spatially explicit mixed fisheries model ISIS-Fish also ran scenarios accounting for MCLs, but only for HKE in GSA 7, implementing a forward, an inverse and a monthly MCL for a total of four scenarios. The forward scenario led to fishing mortalities below Fmsy in 2025 because the value defined for MCL did not account for biomass rebuilding. On the other hand, the fishing mortality achieved using the HCR in the inverse scenario, never fell below Fmsy, because of the unrestricted catches of netters and long-liners. In terms of revenues, both MCL paths led to strong decreases for trawlers. The spatially explicit mixed fisheries models, ISIS-Fish (GSA 7) and SMART (EMU 2), focused on the evaluation of closure areas: existing closure areas, existing closure areas which were seasonal to become permanent, existing closure areas extended to all fishing gears, additional closure areas (only EMU 2), expansion of closure areas by 50% (only EMU 2) and expansion of closure areas by 100% (only EMU 2). ISIS-Fish was applied only for HKE in GSA 7 being the first time this model was used within this working group. The extension of closure areas to all fishing gears (passive gears on top of trawlers) in GSA 7 did not show any improvement, while shifting from a seasonal to a permanent closure showed a decrease in F and an increase in SSB. A decrease of catches of juvenile hake of 20% was observed both with seasonal and permanent closures. Catches of adults increased due to recovery of the stock and considering the low level of initial catches. It should be noted that revenues increased for passive gears but decreased for trawlers. SMART was updated, increasing the spatial resolution of the spatial grid of the model, to be in line with outputs of the ad-hoc contracts preceding the EWG and with ISIS-Fish. None of the scenarios considered for EMU 2 evaluating spatial closures allowed to reach Fmsy by 2025, except for MUT in 10 and NEP in 9 which remains underutilized. SSB shows, nevertheless, an increase across years. None of the scenarios allowed to reduce catches by 20% for all species. All scenarios are associated with a sharp decrease in revenues; spatial closures not widened or seasonal would involve lower decrease of the profits than widened and permanent closures. Loss of profits is more evident for VL12-18 and VL18-24, although the loss is evident for all fleet segments. During EWG 22-01 no explicit comparison between the implementation of an effort regime and a MCL regime was run. The group advices to do so accounting for the limitations encountered in the implementation of MCLs during EWG 22-01. It should be noted that the reduction of GVA is estimated in the short term (up to 2025), but further tests should be done to estimate the trend of GVAs in the mid- and long-term. It is highlighted that given the large number of other species exploited beyond the key ones included in the management plan and in the simulation models, the actual socio-economic impact of the plan remains uncertain. Also, the economic results are presented considering a constant number of vessels, and would differ if the number of vessels is reduced. Additionally, it is difficult to evaluate the socio-economic impact of the MAP on the fleets as at present no socio-economic reference points are used to compare the results against those.
    • Guía para el control de calidad de datos de temperatura y salinidad obtenidos en cruceros oceanográficos regionales

      Grupo de Trabajo Especializado de Base de Datos (GTE-BD) de los Cruceros Regionales (Comisión Permanente del Pacífico Sur (CPPS)Guayaquil, Ecuador, 2022)
      La presente publicación constituye un producto del Grupo de Trabajo Especializado de Base de Datos (GTE-BD) de los cruceros regionales perteneciente a la Comisión Permanente del Pacífico Sur (CPPS), en el cual participaron instituciones de Chile, Colombia, Ecuador y Perú. La guía establece una metodología para el control de calidad de datos de salinidad y temperatura de la columna de agua, obtenidos mediante perfiladores CTD en los cruceros oceanográficos asociados al programa para el Estudio Regional del Fenómeno El Niño (ERFEN) de la CPPS. Las pruebas de calidad propuestas conducen a la asignación de banderas de calidad recomendadas por el programa internacional IODE. Los datos calificados harán parte de la Base de Datos Regional para los diferentes usuarios.
    • An overview of the use of the iron in aquaculture

      Ho, Son Lam; Dang, Tran Tu Tram (2021)
      Iron is a trace element involved in many physiological and biochemical processes of aquatic animals and is necessary for the production and normal functioning of hemoglobin, myoglobin, cytochromes, and many other enzyme systems, maintains the structural integrity of the epithelium and thus suppresses pathogens, iron deficiency induces microcytic anemia in certain fish species, iron-free content in mucus membranes and in other tissues that are one of the first glands to protect the host against infection, iron deficiency can decrease host resistance so that iron supplementation increases host resistance disease. This report not only reviews the iron requirement in fish and crustaceans farming but also its effect on the health status.
    • Environmental assessment of coastal water of Can Gio district - Ho Chi Minh city by sea water quality index

      Nguyen, Hoang Thai; Nguyen, Phi Uy Vu; Bui, Duc Linh; Nguyen, Phi Khanh Phong (2021)
      Assessment of water quality plays an essential role in controlling and monitoring environmental quality for economic development. Based on the monitoring results in 2018-2019, the paper aims to classify the water quality based on SQWI in the coastal waters of Can Gio district, Ho Chi Minh City. Although the SQWI value increased from 35 (in 2018) to 82 (in 2019), the water environment was not considered polluted. However, the results also warn of the pollution level due to high SQWI coliform in Cau Den and Long Hoa in the rainy season.
    • Pollution of total petroleum hydrocarbon in coastal zone Ca Na, Ninh Thuan province

      Le, Trong Dung; Nguyen, Hong Thu; Le, Hung Phu; Phan, Hong Ngoc; Cao, Van Nguyen; Dao, Viet Ha (2021)
      The paper presents the analysis results of total petroleum hydrocarbon (TPH) in the water and sediments of two surveys at 12 stations in the Ca Na sea area in Ninh Thuan province in April 2018 and December 2019. Water samples were extracted by liquid-liquid method with dichloromethane solvent, sediment samples extracted by Soxhlet method, and Dichlorometal. Analysis by gas chromatography with FID detector (GC-FID). The total hydrocarbon content is calculated from the carbon range C9 to C36. The results showed that the concentration of TPH in the water ranged from 1.2 to 32.3µg/l with an average of 11.9±6.2µg/l, nearshore stations in the north (Mui Dinh) have higher concentrations than in the south (Ca Na), the concentration in December 2019 was higher than in April 2018 at most stations. In the sediments, the average TPH content is 4.3µg/gdry, ranging from 1.7-11.0 µg/gdry, showing that the sediment here has not been contaminated with TPH.
    • Composition and antioxidant activity of crude extract from squid Uroteuthis chinensis

      Nguyen, Phuong Anh; Pham, Xuan Ky; Dao, Viet Ha; Phan, Bao Vy; Le, Ho Khanh Hy; Doan, Thi Thiet (2021)
      The antioxidant activities against DPPH free radical of crude extracts using ethyl acetatee and methanol from Uroteuthis Chinensis were studied muscles of, ranged from 13.43% to 41.13%. TLC and FT-IR analysis of several fractions methanol extracts showed the presence of amino acids, peptides, and proteins. SDS-PAGE result of some fractions of methanol extracts described the presence of proteins with a molecular weight of 19-220 kDa. The antioxidant activities of different segments of the Uroteuthis Chinensis were various.
    • Preparation of nanohydroxyapatite from skipjack tuna bone (Katsuwonus pelamis) by alkaline hydrolysis and thermal calcination methods

      Le, Ho Khanh Hy; Dao, Viet Ha; Pham, Xuan Ky; Nguyen, Phuong Anh; Doan, Thi Thiet; Phan, Bao Vy (2021)
      As the main component of bones and teeth, hydroxyapatite (HAp) is considered a vital biomaterial in many fields. Meanwhile, fishbone by-products are abundant sources of HAp. Therefore, this study was conducted to prepare nano HAp from skipjack tuna bone (Katsuwonus pelamis) using alkaline hydrolysis and thermal calcination methods. After pre-treatment of fish bones for removing organic impurities, the bone powders were under alkaline hydrolysis in 1 M NaOH solution at 250o C for 1 hour. This method allows to obtain HAp nanopowders with an average particle size of only 22 nm; whereas, when heating at 600o C for four hours, the calcium formed was on average larger (40 nm) in size than the alkaline hydrolysis product. The HAp nanopowders formed by alkaline hydrolysis had a molar ratio of Ca/P 1.929, higher than that of the calcinated sample (1.848). These Ca/P molar ratios prove that the nano-HAp powders are B-type biological hydroxyapatites confirmed by the FTIR spectrum. In addition, the heavy metal contents of calcium powders are detected within safety limits of regulatory requirements of Vietnam regulations on dietary supplements and functional foods.
    • Hydroxyapatite: physicochemical properties, biological role and marine origin

      Le, Ho Khanh Hy (2021)
      Biomedical materials research aims to find new forms of materials and medical devices, which can able to adapt to the bio-physiological mechanism of the human body, avoid the elimination, therefore helping improve the quality of human life. Hydroxyapatite (HAp) is one of the stable calcium phosphate (CaP) with loBiomedical materials research aims to find new forms of materials and medical devices, which can able to adapt to the bio-physiological mechanism of the human body, avoid the elimination, therefore helping improve the quality of human life. Hydroxyapatite (HAp) is one of the stable calcium phosphate (CaP) with low solubility and Ca/P ratio similar to the Ca/P ratio in bones and teeth (Ca/P = 1.67). These properties allow HAp to be served as bone-regenerating materials or as a drug carrier. Nowadays, most HAp applied materials are products of synthesis processes, but they are still not enough for widespread applications. Therefore, several chemical methods have been developed to obtain natural HAp from marine organisms such as corals, cuttle-bones, seashells, fish scales, fish bones and algae. w solubility and Ca/P ratio similar to the Ca/P ratio in bones and teeth (Ca/P = 1.67). These properties allow HAp to be served as bone-regenerating materials or as a drug carrier. Nowadays, most HAp applied materials are products of synthesis processes, but they are still not enough for widespread applications. Therefore, several chemical methods have been developed to obtain natural HAp from marine organisms such as corals, cuttle-bones, seashells, fish scales, fish bones and algae.
    • Relaciones morfométricas y talla de primera maduración del cangrejo de tierra Cardisoma guanhumi Latreille en la Ciénaga de Zapata.

      Giménez, Enrique; Acevedo, M. (1982)
      Se presenta la relación entre 15 medidas morfométricas en ejemplares de cangrejo de tierra (Cardisoma guanhumi) de le Ciénaga de Zapata. El dimorfismo sexual tanto en los machos como en las hembras se apreció claramente a partir de los 5,0 cm de ancho de carapacho y no es hasta aproximadamente los 7,0 cm que las hembras pueden alcanzar la madurez sexual. Se presentan además, las relaciones ancho y largo carapacho VS peso, así como el por ciento que representan los quelípedos en ambos.
    • Patrones de migración y definición de unidades pesqueras de camarón en el área de Manzanillo.

      Rodríguez, J.; Pérez, A. (1982)
      El análisis de las zonas de mayor abundancia de ejemplares pequeños de camarón (Penaeu notialis y Penaeus schmitti, en el área de pesca de Manzanillo, así como la distribución de las tallas, rendimientos en número y zonas de desove, realizado a partir de los datos de cruceros de prospección camaronera, demuestran la existencia de tres grupos de reclutamiento para P. notialis y P. schmitti. Se discuten las vías de migración mas probables para estos grupos, los cuales pueden ser considerados como unidades pesqueras independientes. Se analiza además, el efecto de la existencia de estas unidades pesqueras sobre el estudio y administración del recurso.
    • Evaluación de la pesquería de camarón del área de Santa Cruz del Sur.

      Pérez, A.; Puga, Rafael (1982)
      Se analiza la evolución de la pesquería de camarón del área de Santa Cruz del Sur respecto a técnicas de pesca y niveles de extracción del recurso en el período 1959-198o. Se calcula la variación estacional media de los rendimientos de la flota comercial a partir de los datos del período 1972-1980 y se estudia su relación con el ciclo biológico de la especie en el área. Mediante la aplicación de modelos globales se estiman, la captura máxima sostenible anual del área y el esfuerzo máximo permisible. Se concluye que el área se halla sobreexplotada y se recomiendan cursos de acción para su recuperación.
    • Évaluation de la qualité microbiologique des poissons transformés artisanalement dans la Commune de Joal –Fadiouth, Département de Mbour (Sénégal)

      Diouf, Alioune Badara Kane; AYSSIWEDE, Simplice B.; DIAWARA, Abdoulaye; MUSABYEMARIA, Bellancille; Direction des Industries de Transformation de la Pêche; Ecole Inter-États des Sciences et Médecine Vétérinaires; Ministère de l’Élevage et des Productions animales (École Inter-États des Sciences et Médecine VétérinairesDakar, Sénégal, 2022)
      La transformation artisanale du poisson est l’une des méthodes de conservation. Les produits obtenus de cette transformation contribuent significativement à la satisfaction des besoins en protéines animales des populations. C’est dans le but de contribuer à l’amélioration de la qualité microbiologique des produits halieutiques transformés artisanalement que nous avons évalué la qualité microbiologique des poissons transformés artisanalement dans la Commune de Joal – Fadiouth,Département de Mbour (Sénégal) notamment, sur le site traditionnel de Tann et amélioré de Khelcom. Notre étude s’est élargie sur l’impact de l’amélioration du site Khelcom sur la qualité du produit. Il est ressorti de nos résultats que sur les 100 échantillons prélevés et répartis équitablement entre les deux sites, seuls 16 sont non satisfaisants dont 13 échantillons contenant des salmonelles et 11 échantillons contaminés par Vibrio parahaemolycticus. Sur le site de Tann, il a été noté la présence de Vibrio parahaemolyticus dans trois échantillons, cinq échantillons contaminés par des salmonelles et huit échantillons dans lesquels ces deux bactéries sont présentes. Par contre, sur le site amélioré de Khelcom, aucun échantillon ne présente un résultat positif. Ainsi, au regard de nos résultats on peut conclure que l’amélioration des sites a un impact positif sur la qualité microbiologique des produits finis