scholarly journals FLORECIMIENTO DE MICROALGAS RELACIONADO CON MORTANDAD MASIVA DE PECES EN EL COMPLEJO LAGUNAR CIENAGA GRANDE DE SANTA MARTA, CARIBE COLOMBIANO.

2016 ◽  
Vol 23 ◽  
Author(s):  
José Ernesto Mancera P. ◽  
Luis Alfonso Vidal V.
Keyword(s):  
Bacterial Activity ◽  
Fish Mortality ◽  
Fish Biomass ◽  
Filamentous Cyanobacteria ◽  
Anoxic Conditions ◽  
The Third ◽  
Dead Fish ◽  
Toxic Gas ◽  
High Concentrations ◽  
Flagellate Algae

A discontinuous phenomenon of massive fish mortality occurred in the estuarine lagoonal complex of the Ciénaga Grande de Santa Marta, Colombia, in July and August 1994. The first event occurred from the 15th to the 19th of July, the second took place one month later around the 20th of August, and the last one was evident from the 26th to the 31st of the same month. High concentrations of Cf. Anabaenopsis sp., a filamentous cyanobacteria, reported in the literature as highly toxic, may have been related to the causes of the first event. An increase in phosphorus concentrations resulting in massive blooms of cyanobacteria and flagellate algae of nano and picoplankton could explain the hypoxic and anoxic conditions associated to the third event of massive fish mortality. However, other possible causes, such as toxic gas liberation from the sediment and anoxia from bacterial activity cannot be roled out. The dead fish biomass was not quantified, but information obtained from fishermen suggests for sea catfish (Ariidae) values well over 20 tons. The massive death phenomenon here reported seems to be the strongest in the last years.

Bank filtration: a suitable process for the removal of iodinated X-ray contrast media?

2004 ◽  
Vol 50 (5) ◽  
pp. 261-268 ◽  
Author(s):  
S. Schittko ◽  
A. Putschew ◽  
M. Jekel
Keyword(s):  
Drinking Water ◽  
Contrast Media ◽  
Surface Waters ◽  
Sampling Period ◽  
Transformation Products ◽  
Bank Filtration ◽  
Anoxic Conditions ◽  
X Ray ◽  
High Concentrations ◽  
Media Concentration

After bank filtration, effluent influenced surface waters are often used as raw drinking water. It is known that high concentrations of iodinated X-ray contrast media are detectable in such surface waters and thus, more knowledge about the behaviour of the contrast media during bank filtration is necessary and the subject of investigations in this study. The adsorbable organic iodine (AOI), four widely used iodinated X-ray contrast media and four possible transformation products were quantified in an influenced lake, five groundwater wells and a drinking water well. Under anoxic conditions the AOI as well as the concentration of the contrast media are decreased by bank filtration, whereby the AOI is decreased by 64% and the contrast media concentration can be reduced up to 95%, depending on the compound. In the raw drinking water the following average concentrations were determined: Iopromid <20 ng/L, Diatrizote 166 ng/L, Iopamidol 166 ng/L and Iohexol 34 ng/L. Instationary conditions during the sampling period indicate that, at least under anoxic conditions, a large part of the contrast media and transformation products, which are still iodinated, may be associated to colloids and/or humic material.

scholarly journals The use of a ‘first-wave’ model to study the effect of nutrition on ovarian follicular dynamics and ovulation rate in the sheep

Reproduction ◽  
2010 ◽  
Vol 140 (6) ◽  
pp. 865-874 ◽  
Author(s):  
C Viñoles ◽  
B Paganoni ◽  
K M M Glover ◽  
J T B Milton ◽  
D Blache ◽  
...  
Keyword(s):  
Body Condition ◽  
Wave Model ◽  
Ovulation Rate ◽  
Short Term ◽  
Metabolic Hormones ◽  
Follicular Waves ◽  
Follicular Wave ◽  
The Third ◽  
High Concentrations ◽  
Follicular Dynamics

We have developed an experimental model in which groups of ewes are simultaneously experiencing the first ovarian follicular wave of their oestrous cycle. We used this ‘first-wave model’ in a 2×2 factorial experiment (ten ewes per group) to study the effect of body condition (BC) and a short-term supplement on follicular dynamics and ovulation rate. The ‘first-wave’ was established by giving ewes three injections of prostaglandin (PG), 7 days apart. The 6-day supplement (lupin grain) began 2 days after the second PG injection and continued until the third. Follicles were studied by ultrasound, and blood was sampled to measure glucose and hormones. The supplement increased (P<0.01) the concentrations of glucose, insulin and leptin, decreased FSH concentrations (P<0.01) and tended to increase oestradiol concentrations (P=0.06). The supplement tended to increase the number of 3 mm follicles (P=0.06). Compared with low-BC ewes, high-BC ewes had more follicular waves (P<0.05), higher concentrations of insulin, leptin and IGF1 (P<0.05) and tended to have higher FSH concentrations (P=0.09). Leptin and insulin concentrations remained high until the end of supplementation in high-BC ewes, whereas they decreased after the third day of supplementation in low-BC ewes. In conclusion, high concentrations of metabolic hormones in fat ewes are associated with the development of more follicular waves. When a supplement is superimposed on this situation, changes in glucose and metabolic hormones allow more follicles to be selected to ovulate.

scholarly journals Towards End-2-End modelling in a consistent NPZD-F modelling framework (ECOSMOE2E_vs1.0): Application to the North Sea and Baltic Sea

2018 ◽  
Author(s):  
Ute Daewel ◽  
Corinna Schrum ◽  
Jed Macdonald
Keyword(s):  
Baltic Sea ◽  
North Sea ◽  
Food Chain ◽  
Current System ◽  
Ecosystem Model ◽  
Trophic Levels ◽  
Production Model ◽  
Fish Mortality ◽  
Fish Biomass ◽  
Trophic Chain

Abstract. Coupled physical-biological models usually resolve only parts of the trophic food chain and hence, run the risk of neglecting relevant ecosystem processes. Additionally, this imposes a closure term problem at the respective “ends” of the considered trophic levels. Here we propose a consistent NPZD-Fish modelling approach (ECOSMO E2E) to address the above-mentioned problem in lower trophic ecosystem modelling, and to understand how the implementation of higher trophic levels in a NPZD model affects the simulated response of the combined North Sea and Baltic Sea ecosystem. On the basis of the coupled ecosystem model ECOSMO II we implemented one functional group that represents fish and one group representing macrobenthos in the 3d model formulation. Both groups are linked to the lower trophic levels and to each other via predator-prey relationships. The model allows investigating bottom-up impacts on primary and secondary production and cumulative fish biomass dynamics, but also top-down mechanisms on the lower trophic level production. Model results for a ten-year long simulation period (1980–1989) were analysed and discussed with respect to the observed pattern. To address the relevance of the newly implemented trophic levels for the simulated model response, we compare the performance of the ECOSMO E2E to a respective truncated NPZD model (ECOSMO II), which simulated the same time period. Additionally, we performed scenario tests to analyse the new role of the zooplankton mortality closure term in the truncated NPZD and the fish mortality term in the end-to-end model, which summarizes pressure imposed on the system by fisheries and mortality imposed by apex predators. We found that the model-simulated macrobenthos and fish spatial and seasonal pattern agree well with current system understanding. Considering a dynamic fish component in the ecosystem model resulted in slightly improved model performance with respect to representation of spatial and temporal variations in nutrients, changes in modelled plankton seasonality and nutrient profiles. Model sensitivity scenarios showed that changes in the zooplankton mortality parameter are transferred up and down the trophic chain with little attenuation of the signal, while major changes in fish mortality and in fish biomass cascade down the food chain.

Effect of Sodium Bicarbonate Supplementation on 2000-m Rowing Performance

2014 ◽  
Vol 9 (1) ◽  
pp. 139-144 ◽  
Author(s):  
Ruth M. Hobson ◽  
Roger C. Harris ◽  
Dan Martin ◽  
Perry Smith ◽  
Ben Macklin ◽  
...  
Keyword(s):  
Sodium Bicarbonate ◽  
Repeated Measures ◽  
Base Excess ◽  
Repeated Measures Anova ◽  
The Third ◽  
Design Time ◽  
Rowing Performance ◽  
Rowing Ergometer ◽  
High Concentrations ◽  
Double Blinded

The ability to buffer H+ could be vital to exercise performance, as high concentrations of H+ contribute to the development of fatigue.Purpose:The authors examined the effect of sodium bicarbonate (SB) supplementation on 2000-m rowing-ergometer performance.Methods:Twenty male rowers (age 23 ± 4 y, height 1.85 ± 0.08 m, mass 82.5 ± 8.9 kg, 2000-m personal-best time 409 ± 16 s) completed two 2000-m rowing-ergometer time trials, separated by 48 h. Participants were supplemented before exercise with 0.3 g/kg body mass of SB or a placebo (maltodextrin; PLA). The trials were conducted using a double-blinded, randomized, counterbalanced crossover study design. Time to complete the 2000-m and time taken for each 500-m split were recorded. Blood lactate, bicarbonate, pH, and base excess were determined preexercise, immediately postexercise, and 5 min postexercise. Performance data were analyzed using paired t tests, as well as magnitude-based inferences; hematological data were analyzed using a repeated-measures ANOVA.Results:Using paired t tests, there was no benefit of SB over PLA (P = .095). However, using magnitude-based inferences there was a likely beneficial effect of SB compared with PLA (PLA 412.0 ± 15.1 s, SB 410.7 ± 14.9 s). Furthermore, SB was 0.5 ± 1.2 s faster than PLA in the third 500 m (P = .035; possibly beneficial) and 1.1 ± 1.7 s faster in the fourth 500 m (P = .004; very likely beneficial). All hematological data were different between SB and PLA and were different from preexercise to postexercise.Conclusion:SB supplementation is likely to be beneficial to the performance of those competing in 2000-m rowing events, particularly in the second half of the event.

scholarly journals A selective fish mortality and some notes on Rhabdosargus sarba at Kosi Bay, South Africa

Koedoe ◽  
2002 ◽  
Vol 45 (2) ◽  
Author(s):  
R. Kyle
Keyword(s):  
South Africa ◽  
Fish Mortality ◽  
Local Residents ◽  
Dead Fish

On 6 July 2000, while crossing Lake Nhlange, the largest of the Kosi Bay lakes, several dead fish were seen, lying bloated on the surface. On investigation they were found to be large Natal stumpnose Rhabdosargus sarba. Occasionally, during twenty years of residence at the Kosi lakes, the author has seen individual Natal stumpnoses dead or dying in this lake, particularly in winter, but never so many at one time. On investigation, by questioning other local residents, it was found that the mortality had been taking place for several days and it subsequently extended for at least another 14 days.

Evolution of river pollutions under the influence of local hydro-climatic changes - the example of the Bienne River (Jura Mountain, France)

2020 ◽  
Author(s):  
Elie Dhivert ◽  
François Gibon ◽  
Karine Hochart ◽  
Bertrand Devillers
Keyword(s):  
Climatic Changes ◽  
Fish Mortality ◽  
Risk Level ◽  
Rainfall Regime ◽  
Pollution Levels ◽  
Resilience Process ◽  
Wide Range ◽  
River Quality ◽  
High Concentrations ◽  
The Impact

&lt;p&gt;In application of the EU Water Framework Directive, many actions have been undertaken in order to reduce pollution levels in river systems. However, for certain catchments, the resilience process is not occurring as expected. In the Bienne River basin, metals discharge has plummeted since the 1990s, following the implementation of a better industrial waste management, as well as an important industrial restructuring. Nevertheless, this river has been regularly affected by massive fish mortality over the 2012-2019 period. This phenomenon, never identified before, is becoming recurrent. Organic tissues sampled in dead fish contained high concentrations of metals in association with other toxics. In this context, this study introduces a transdisciplinary approach in order to: (i) analyse spatial and temporal evolutions of pollutions in the Bienne River, (ii) evaluate potential ecotoxicological impacts associated, (iii) identify interactions with local hydro-climatic changes. Metallic and organic pollutants were analysed over different stations and at multi-temporal scales, associating sedimentary archives, suspended matters and passive water samplers. These analyses highlight the impact on the river quality of both current and legacy pollutions, particularly during prolonged low-water periods and high discharge events. Ecotoxicological analyses emphasize a severe risk level in the case of polluted sediments remobilization, especially because of heavy metals and PAH contamination. Geochemical evidence of such remobilization events has been recorded over the last decade in a sedimentary core sampled in the downstream part of the Bienne River. Hydrological data recorded in the Bienne River gauging stations since 1971 attests of an important year-to-year variability, although changes in the river discharge distribution are ongoing. Data has shown a higher frequency of both the lowest and the highest outflows over the 2012-2019 period compared to the rest of the hydrological recording. Hydro-climatic variables coming from in-situ measurements and satellite data (GPM-IMERG6) has also shown significant modifications in the rainfall regime over this period, especially in the augmentation of dry spells and heavy rainfall episodes. Those modifications agree well with the discharge change observations. This study brings out knock-on impacts of combined geochemical, ecotoxicological and hydro-sedimentary issues on the fate of aquatic ecosystems, especially under the influence of local hydro-climatic changes and their implications on hydrological regimes. Those results aim at reducing uncertainties concerning the evolution of the river quality by highlighting such a tipping point for environmental conditions. In addition, such a study helps us to grasp the complexity of local stakes regarding the multiple interests of a wide range of stakeholders and policy makers involved on the field.&lt;/p&gt;

Surface carbohydrate changes onOnchocerca lienalislarvae as they develop from microfilariae to the infective third-stage inSimulium ornatum

1988 ◽  
Vol 62 (3) ◽  
pp. 195-205 ◽  
Author(s):  
P. J. Ham ◽  
A. J. Smail ◽  
B. K. Groeger
Keyword(s):  
Wheat Germ ◽  
Helix Pomatia ◽  
Kidney Bean ◽  
Con A ◽  
The Third ◽  
Lentil Lectin ◽  
Natural Vector ◽  
Third Stage ◽  
High Concentrations ◽  
Surface Carbohydrates

ABSTRACTUse was made of seven FITC labelled lectins as tools to investigate the surface ofOnchocerca lienalislarvae as they develop through to the infective third-stage in a natural vector,Simulium ornatum. The lectins were derived fromCanavalia ensiformis(Con A),Lens culinaris(lentil),Triticum vulgaris(wheat germ),Arachis hypogaea(peanut),Helix pomatia, Phaseolus vulgaris(kidney bean) andTetragonolobus purpureus(asparagus pea). Between 70 and 100 living parasites were examined for each developmental stage; i.e. skin microfilariae, late first-stages, second-stages, preinfective third-stages and infective third-stages isolated from the mouth parts of the flies. None of the lectins used bound to the surface of the microfilariae. However, progressive binding to the cuticle of the first- and second-stages was observed using Con. A, lentil lectin and wheat germ agglutinin (WGA). Following moulting to the third-stage, binding of these three lectins declined. Furthermore, as these lectins decreased, peanut andHelix pomatialectins progressively increased in their binding, despite the fact that they showed little or no binding to the first- and second-stages; stages at which Con A, lentil and WGA were at their maximum. Asparagus pea and kidney bean lectins failed completely to bind to any of the larvae examined. Carbohydrate inhibition tests showed that the lectin was indeed binding specifically to glycoconjugates on the parasite surface. WGA binding was not inhibited by prior incubation with N-acetyl-D-glucosamine, even at high concentrations, but neuraminic acid did completely inhibit its binding. Judging from the patterns of binding on the nematodes themselves, the carbohydrates may not be vector in origin, but derive from the worms. The lectin specificities indicate that initially mannose/glucose type derivatives are present on the surface. Following moulting to the third-stage these are progressively replaced, or overlaid with galactosamine type derivatives, also present on the infective third-stage as it enters the bovine host. The availability of these surface glycoconjugates to attack mediated by natural insect lectins may be of importance in the parasite regulatory mechanisms of the blackfly. Variability in these surface carbohydrates, and in the response to them could well be a contributing factor in the cytospecific variation inS. damnosumsusceptibility to geographical variants ofO. volvulus.

scholarly journals Effect of heavy metals (Cd, Cu, and Zn) on feeding indices and energy reserves of the cotton boll worm Helicoverpa armigera Hübner (Lepidoptera: Noctuidae)

2014 ◽  
Vol 54 (4) ◽  
pp. 367-373 ◽  
Author(s):  
Adel Baghban ◽  
Jalal Jalali Sendi ◽  
Arash Zibaee ◽  
Roya Khosravi
Keyword(s):  
Heavy Metals ◽  
Helicoverpa Armigera ◽  
The Third ◽  
Cholesterol Levels ◽  
Helicoverpa Armígera ◽  
High Concentrations ◽  
Biochemical Indices ◽  
Lepidoptera Noctuidae ◽  
Helicoverpa Armigera Hubner ◽  
Third Instar Larvae

Abstract Third-instar larvae of Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) were exposed to 12.5, 25, and 50 mg/kg concentrations of cadmium (Cd). The third-instar larvae were also exposed to 25, 50, and 100 mg/kg concentration of copper (Cu), and 25, 50, and 100 mg/kg concentrations of zinc (Zn). The heavy metal concentrations were each introduced separately into the artificial diet of the third-instar larvae. The third-instar larvae were 24 h old at the start of the treatment. The larvae were maintained in controlled conditions (26±1°C, 65±10% RH and 16L : 8D h) for 7 days. The feeding indices and the level of total protein, glycogen, cholesterol, and triglyceride were measured after the treatments. The results showed that high concentrations of Cd significantly increased approximate digestibility (AD). The relative growth rate (RGR) was significantly enhanced with a 25 mg/kg concentration of Cu. Efficiency of conversion of the ingested food (ECI%) increased significantly with lower concentrations of copper (25 and 50 mg/kg). The amount of cholesterol was also enhanced with 12.5 and 25 mg/kg concentrations of cadmium while the amount of triglyceride was significantly reduced in all Cd treatments. Glycogen, protein, and cholesterol were significantly enhanced in all Cu treatments. The amount of triglycerides at 25 and 50 mg/kg of Cu was significantly increased. Glycogen in all Zn treatments was significantly increased. Protein and cholesterol levels showed significant reduction with a 25 and 50 mg/kg concentration of zinc while triglyceride was enhanced with a 50 mg/kg concentration of Zn. It is clear from the present results that the presence of such heavy metals in the environment has an intense impact on H. armigera as far as food consumption and biochemical indices are concerned. Therefore, a need is shown for a more comprehensive study on the life table and immunology of this insect, under the presence of heavy metals.

scholarly journals Changes in plasma concentration of flavonoids after ingestion of a flavonoid-rich meal prepared with basic foodstuffs

2019 ◽  
Vol 9 (9) ◽  
pp. 558
Author(s):  
Ryo Mannen ◽  
Michiko T Yasuda ◽  
Ayami Sano ◽  
Toshinao Goda ◽  
Kayoko Shimoi ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Plasma Concentrations ◽  
Enzyme Hydrolysis ◽  
Single Type ◽  
Flavonoid Content ◽  
Urinary Recovery ◽  
The Third ◽  
High Concentrations ◽  
Habitual Intake ◽  
Hydrolysis Of

Background: As flavonoids have a variety of functions, such as antioxidant activity, there is growing interest in the development of flavonoid supplements. However, there have been reports of DNA damage due to exposure to flavonoids at high concentrations in rats, which could suggest that a habitual intake of flavonoid supplements may cause toxicity. Therefore, we considered that ingesting flavonoids from a typical meal combined basic foodstuffs are safe because of unlikely to result high concentrations like supplements, and focused on the intake of flavonoids from a typical meal. Thus, this study investigated the absorption of flavonoids in humans after the consumption of a typical meal. Methods: On the first 2 days of the study, seven healthy volunteers were provided with low-flavonoid meals (flavonoid content below the detection limit by HPLC: less than 0.24 mg/meal) three times a day as a washout. A flavonoid-rich meal (40.44 ± 1.49 mg/meal) was then provided for breakfast on the third day. Blood was collected from all volunteers 0, 2, 3, 7, 8, and 9 h after the flavonoid-rich meal was consumed. After enzyme hydrolysis of the plasma, the plasma concentrations of flavonoids aglycone of quercetin, daidzein and genistein were measured using LC-MS. Urine was also collected and pooled 24 h after the flavonoid-rich meal was consumed. Thereafter, the urine was treated with enzyme hydrolysis, and the measurement of urinary flavonoids was performed. Results: Plasma flavonoid peaks were observed 8 h after consumption of the flavonoid-rich meal (quercetin: 4.29 ± 1.46 μM, daidzein: 0.51 ± 0.41 μM, genistein: 0.91 ± 0.73 μM). Furthermore, flavonoids were confirmed to be present in plasma even at 9 h after the intake meal. The urinary recovery of flavonoids was 3.43 ± 1.50% for quercetin, 13.87 ± 6.68% for daidzein, and 16.89 ± 11.40% for genistein. Conclusion: These results suggest that consuming a typical meal that combines a variety of basic foodstuffs delays attainment of the plasma flavonoid peak compared with consuming a single type of food or supplements as previously reported. In addition, the flavonoid urinary recovery were also reduced compared with those previously reported. 

scholarly journals ORGANIC GEOCHEMISTRY OF HUMIC ACIDS FROM A NEOGENE LIGNITE SAMPLE, BULGARIA

2017 ◽  
Vol 43 (5) ◽  
pp. 2398
Author(s):  
M. Stefanova ◽  
S.P. Marinov
Keyword(s):  
Humic Acids ◽  
Organic Geochemistry ◽  
Distribution Patterns ◽  
Bacterial Activity ◽  
Long Chain Fatty Acids ◽  
Plant Origin ◽  
Higher Plant ◽  
Acidic Fraction ◽  
High Concentrations ◽  
Very High

Humic substances naturally occur in Miocene/Pliocene-aged lignite at very high concentrations. Here biomarkers in the bitumen-free extract of humic acids from Thracian lignite, Bulgaria, are studied. Applying methods of organic geochemistry a broad range of compounds are isolated and characterised. Species are classified according to abundance, possible source input and diagenetic transformation. A feature of humic acids derived from Thracian coal is the extremely high content of 16α(H)Phyllocladane, ~60% of aliphatic fraction, or 1.6 wt.% of initial lignite. The high diterpenoids content, especially with abietane skeleton, proved the conifer contribution to the peat-forming helophytes, i.e. Cupressaceae s. str., Podocarpaceae, Araucariaceae, Taxodiaceae, Phyllocladus, Piceae. Tightly-trapped, linear long-chain fatty acids (FAs) are the main constituents of the acidic fraction of humic acids. Their distribution patterns indicate a dominant higher plant origin. The presence of αOH-FAs and hopanoid acids assumes bacterial activity in the plant material reworked. A hint for the input of plant biopolymers, i.e. cutin, suberin, is the relative high content of “even” carbon numbered ωΟΗFAs and α,ω-alkanedioic FAs. “Even” numbered short-chain ωΟΗFAs could originate from cutin-derived constituents of the needles of numerous species of gymnospermous families.

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