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Absinthe is an anise-flavored alcohol that is typically served by adding cold water to form a cloudy green louche, similar to the cloudy white louche of ouzo. This microemulsion formation, due to the competing interactions within the oil–alcohol–water system, has been termed the ouzo effect. Previous work has examined the ternary oil–alcohol–water phase diagram in ouzo and limoncello. Additional work has also characterized the droplet size and stability of microemulsions in ouzo, limoncello, and pastis. However, less work has been done to examine the effect of temperature on louche formation despite the fact that the louche is traditionally formed by adding ice cold water. This work demonstrates that both the maximum turbidity and the fraction of alcohol at maximum turbidity are temperature-dependent. The louche formation can be fit with a logistic curve, and the resulting fit parameters are linear with temperature. Optical images show that the increased turbidity correlates with an increase in the number of droplets in the microemulsion.

Beer subjected to forced aging by five (Medium) or ten (High) heat/chill cycles (60 °C 48 h/0 °C 24 h) showed increased turbidity from 5.4 ± 0.4 EBC units without forced aging to 12.9 ± 0.7 and 48 ...

Increased turbidity, a common human-induced aquatic disturbance, can potentially have major impacts on predator–prey interactions via effects on key foraging and antipredator behaviours, on the repeatability of these behaviours (i.e. on animal personalities) and on behavioural syndromes (correlations among behaviours). Here, we repeatedly assayed individual western mosquitofish, Gambusia affinis, across a range of turbidity levels (low, intermediate, high) to test the degree to which a suite of behaviours (activity, exploration, sociality, responses to olfactory predator cues) scaled with increasing turbidity. In particular, we tested the a priori hypothesis, based on previous work, that fish show stronger behavioural repeatability and behavioural correlations when perceived predation risk is high. While individuals in all treatments responded to predator cues by reducing activity and exploration, those assayed in intermediate turbidity exhibited the strongest antipredator responses. Consistent with our prediction that repeatability should be greatest in high risk, significant behavioural repeatability was only detected in antipredator behaviours at intermediate turbidity. Significant correlations among behavioural traits were detected in all turbidity treatments but primarily under threat of predation – not when predator cues were absent (with one exception). This study demonstrates that levels of human-induced environmental change may interact with predation risk to shape both mean behavioural responses as well as patterns of behavioural correlations within and among individuals.

Physicochemical characteristics, antioxidant activities and emulsifying properties of porcine plasma protein hydrolysates (PPPH) modified with oxidized tannic acid (OTA) or oxidized chlorogenic acid (OCA) were investigated. The formation of complexes was showed by increased turbidity, and both OTA and OCA were covalently attached to PPPH as shown by the significantly decrease in free amino group contents ( P P

Sawah Liek and Tungku Sadah have increased turbidity during the rainy season, 629 NTU. Sawah Liek and Tungku Sadah are 845 m and 888 m above sea level and flow by gravity at Sungai Andok Reservoir, 802 m. Sawah Liek has a production of 5 l/s for 428 customers and Tungku Sadah 10 l/s for 2,806 customers. One of the causes of turbidity fluctuation during rain is planting activities which degrade the area of land cover, increase runoff and minimize infiltration into the area that the flow from the source decreases every year. Water consumption for customers of Sawah Liek is 202 l/person/day and Tungku Sadah 62 l/person/day is smaller than the category of small towns of 130 l/person/day. The installed slow sand filter is unable to handle the turbidity during the rain in exceeds of 50 NTU. The maximum produced by the installed slow sand filter is 2.67 l/s. Changes in the function of the filter installed at a high-speed sand filter can increase production to 26.7 l/s and overcome turbidity fluctuations can be accomplished by improving the system with a complete treatment facility or an incomplete processing facility consisting of a screen, a large chamber, coagulation, and flocculation, filtration and disinfection.

Depth filtration has a long history in both bioprocessing and water treatment, with the earliest records of water purification by depth filtration dating back 4000 years. The renewed interest in depth filtration for bioprocessing has been driven by the push towards single-use manufacturing technologies along with the increased turbidity arising from improvements in cell density and product titer. This review highlights the key principles, developments, and applications of depth filtration systems, including growing opportunities for use of depth filtration for both initial clarification and for treatment of in-process streams to reduce host cell proteins and remove key foulants to improve the overall performance of the downstream process.

Groundwater, as the mainresource of drinking water in the Republic of Srpska, is sometimes neglected regarding quality monitoring. It is especiallya characteristic of rural water supply sources as autonomous waterworks, individual intakes and wells. For the first time comprehensive analyses of the groundwater quality in rural areas of Srebrenica municipality have been provided in 2010. The results are more than interesting. Beside some standard problems in physic-chemical properties like increased turbidity, iron and manganese, there was emerged problem of increased fluoride concentration in more than one third samples of groundwater. The study of fluoride concentration, given in this paper, includes the causes of this phenomena and possible health impacts. It defines geological setting, or precisely mineralogical properties of the rocks and their interaction with groundwater, as a key factor of the problem. Further, analyses include recommendations regarding future exploration areas with probably same effect of the geological setting on groundwater quality in the territory of the Republic of Srpska. It is very important because the problems related to the long-term consumption of groundwater with fluoride concentration above 1.2 mg/L could be a trigger for very serious diseases like dental and skeletal fluorosis, diseases of pineal gland, kidneys, urinary bladder, thyroid gland, gastro-intestinal tract etc. Keywords: concentration, drinking water fluoride, geology, health, Srebrenica. DOI: http://dx.doi.org/10.7251/JEPM1709069J

The large variability in rainwater quality both in time and location as well as the relatively small number of tests make the preliminary assessment of economic exploitation of these waters difficult. Determining the relation between the conditions and location of rainwater collection and rainwater quality would help to indicate the range of options for rainwater use as well as parameters that require improvement. The aim of the presented article is to establish chosen physical, chemical and microbiological parameters of rainwater and, based on the results obtained, to determine the possibilities for a safe use of these waters in households. The research had been carried out for two years. Samples of chosen rainfalls were collected from spring to autumn from the following roofing materials: concrete roof tiles, ceramic roof tiles, zinc coated metal sheets and epoxy coated. The physical, chemical and microbiological quality assessment has been conducted basing on the following parameters: reaction, turbidity, electrical conductivity, concentration of biogenic compounds, concentration of chosen elements, number of Escherichia coli as well as number faecal streptococci. A significant bacterial contamination, a decreased pH and an increased turbidity of rainwaters were identified, depending on the parameters of the roofing washed by rainfalls and the intensity and frequency of precipitation.

Increased water turbidity is considered a primary cause of the loss of seagrass meadows. This paper first quantified the interactive influence of different combinations of turbidity and duration on the responses of Zostera marina plants in terms of survivorship, morphology and growth. The recovery potential of Z. marina plants, as well as the degrees of potential correlations between key factors induced by the increased turbidity and the survival and growth variables, were assessed. The LT50 (lethal time that caused an increase in mortality to 50% of that of the control) and EC50 (effect concentration, i.e., turbidity level that caused a decrease in growth to 50% of that of the control) were calculated to reveal the quantitative relationship between turbidity and duration that resulted in limiting effects on the survival and growth of Z. marina plants. Z. marina plants were exposed to different combinations of water turbidity [4 (control), 50, 100, 200, 300 and 400 NTU] and duration (5, 10, 15 and 20 days), and then the plants were transferred to the control condition for over 30 days under laboratory conditions. The results showed that the recovery effort (the percentage of the survival of plants at the end of recovery to that of plants at the end of direct turbidity stress) of Z. marina exposed to different combinations of turbidity and duration was lower than 100%, indicating that short-term periods of increased water turbidity would lead to long-term effects on the survival of Z. marina plants. Water turbidity and duration displayed a significant interactive effect on the survival and growth of Z. marina plants. Regression analysis revealed that the relationship between water turbidity and duration that resulted in limiting effects on the survival and growth of Z. marina could be described as a strong inverse function. Spearman correlation analysis showed that the decrease in survival and growth of Z. marina plants was mostly caused by increased silt load in turbid waters, and subsequently by light reduction. This study will further develop our understanding of the degradation and disappearance of seagrass meadows induced by increased turbidity.

The MW 7.1 Darfield (Canterbury) earthquake, 4 September 2010, generated widespread hydrological effects in New Zealand ranging from instantaneous changes of piezometric levels, to more sustained post-seismic changes in spring flow, river discharge and groundwater levels, and increased turbidity and declined yields of water abstracted from wells. Four years later, piezometric levels remained elevated in deeper (>40 m) aquifers along the north-western (upper) side of the Canterbury Plains near the Greendale Fault, with changes in mean piezometric level reaching +13 m. Eigen modelling suggests that sustained high groundwater was not the result of changes in abstraction or land surface recharge. Step-drawdown tests at six wells within 15 km of Greendale Fault were carried out prior to the earthquake, and were re-tested following fault-rupture. Eden-Hazel analysis of discharge/drawdown relationships discriminates potential sources of head losses, and how these changed (or otherwise) as a result of the earthquake. Objective application of Eden-Hazel analysis provided confidence levels for the interpretation, including when step tests provide reliable/unreliable estimates of transmissivity change. Increases in both aquifer losses and well losses were observed in four wells, reflecting both a change in sediment transmissivity and decrease in well efficiency. At two locations, the data were unable to provide results that can be interpreted with confidence. As the majority of local groundwater flow occurs through high permeability open framework gravel lenses, we suggest that reduction in the permeability of these gravels, due to fine-sediment incursion, is the cause of the reduction in transmissivity and increase in well losses. This article is protected by copyright. All rights reserved.

Much work has been done to understand the self-assembly properties of collagens from mammals. However, there is little information about fish-sourced collagens that are advantageous in certain applications. In this study, the self-assembly dynamics of tropocollagen (with telopeptides) and atelocollagen (without telopeptides) extracted from snakehead (Channa argus) skins was studied with turbidity, dynamic rheology, scanning electron microscopy (SEM), and quantitative percentage of self-assembly. Turbidity results indicate that the self-assembly of fish-sourced collagens followed the nucleation-growth two-step model, while rheological results unveiled two growth stages in the development of collagen gels. Based on SEM, telopeptides promoted the formation of thicker fibrils and increased the density of network that provided the structural basis of increased turbidity and strengthened storage and loss moduli. The SEM data were supported by the increased percentage of self-assembled collagens by telopeptides. Findings from this work may facilitate the understanding of structures and functions of products containing fish-sourced collagens and their application.

The effect of reciprocating agitation thermal processing (RA-TP) on quality of canned beans was evaluated in a lab-scale reciprocating retort. Green beans were selected due to their soft texture and sensitive color. Green beans (2.5 cm length × 0.8 cm diameter) were filled into 307 × 409 cans with carboxylmethylcellulose (0–2%) solutions and processed at different temperatures (110–130 °C) and reciprocation frequency (1–3 Hz) for predetermined heating times to achieve a process lethality (Fo) of 10 min. Products processed at higher temperatures and higher reciprocation frequencies resulted in better retention of chlorophyll and antioxidant activity. However, high reciprocation frequency also resulted in texture losses, with higher breakage of beans, increased turbidity and higher leaching. There was total loss of product quality at the highest agitation speed, especially with low viscosity covering solutions. Results suggest that reciprocating agitation frequency needs to be adequately moderated to get the best quality. For getting best quality, particularly for canned liquid particulate foods with soft particulates and those susceptible to high impact agitation, a gentle reciprocating motion (~ 1 Hz) would be a good compromise.

The purpose of this study was to investigate the quality characteristics of instant rice noodles made from rice flour with different harvest times rice processed products. The physicochemical characteristics of three different types of rice flour were investigated, including common rice flour (CRF, harvested in 2012), stored rice flour (SRF, harvested in 2008) and CSRF (CRF mixed with SRF). Instant rice noodles were manufactured with the three types of rice flour, and their quality and sensory characteristics were investigated. The water-binding capacity of rice flour was highest in CSRF. Regarding setback on RVA pasting viscosity, SRF and CSRF showed higher values than CRF. Water absorption after cooking of instant rice noodles was highest in common rice noodles (CON). The volume after cooking of instant rice noodles increased in rice noodles with stored rice flour (SRN). Turbidity of rice noodles using CSRF (CSRN) was higher value than that of CON. In texture properties, CON displayed the highest hardness, adhesiveness, springiness, and chewiness. In the sensory evaluation, overall acceptability values of CON were significantly higher than those of other rice noodles (SRN and CSRN). It was concluded that rice noodles with stored rice flour have increased turbidity with reduced texture and overall preference. This study suggests that addition of CRF may result in significantly increased overall quality of instant rice noodles prepared by SRF.

Lake Markermeer, a large shallow lake in The Netherlands, suffers from turbidity and ecology problems. As part of a study aiming to mitigate these problems, we study flocculation processes in the lake; in particular, the possible mutual flocculation between algae and re-suspended bed sediments. We show that sediment re-suspended from the bed of the lake can flocculate, forming flocs for which size is a function of the turbulence level in the water column. Moreover, we also demonstrate that algae and re-suspended bed sediments can mutually flocculate, yielding organic-inorganic aggregates. These aggregates have different features to those of their individual components, some of which have been measured and characterized in this paper. Furthermore, the characteristics of the resulting organic-inorganic flocs are strongly influenced by the type of algae in the aggregate. We found that, in the case of flocs consisting of bed sediments and filamentous algae, flocculation yields smaller flocs than for bed sediments only, resulting in an increased turbidity in the water column. In the case of flocs consisting of bed sediments and colonial algae, flocs grow faster and become larger than bed sediment flocs, which may result in the depletion of most colonies from the water column.

Drinking water related infections are expected to increase in the future due to climate change. Understanding the current links between these infections and environmental factors is vital to understand and reduce the future burden of illness. We investigated the relationship between weekly reported cryptosporidiosis and giardiasis (n = 7,422), extreme precipitation (>90th percentile), drinking water turbidity, and preceding dry periods in a drinking water system located in greater Vancouver, British Columbia, Canada (1997–2009) using distributed lag non-linear Poisson regression models adjusted for seasonality, secular trend, and the effect of holidays on reporting. We found a significant increase in cryptosporidiosis and giardiasis 4–6 weeks after extreme precipitation. The effect was greater following a dry period. Similarly, extreme precipitation led to significantly increased turbidity only after prolonged dry periods. Our results suggest that the risk of cryptosporidiosis and giardiasis increases with extreme precipitation, and that the effects are more pronounced after a prolonged dry period. Given that extreme precipitation events are expected to increase with climate change, it is important to further understand the risks from these events, develop planning tools, and build resilience to these future risks.

The effect of 0.1-0.5% (w/w) sodium-alginate (SA) with three molecular-weights (2660, 3890 and 4640kDa) on the water-holding capacity (WHC) of chicken-breast myosin gels was investigated. The results showed that 0.1-0.5% SA of three molecular-weights increased the WHC of myosin-SA gels, and the heavier SA induced a higher WHC. Electrostatic-interactions and hydrogen-bonding contributed to the intermolecular aggregation in the myosin-SA system and enhanced its intermolecular interactions by overcoming the steric hindrance effect of SA with heavier molecules. This aggregation induced the increased turbidity, transition temperature and the decreased surface hydrophobicity of myosin-SA solutions and the formation of an inhomogeneous network with large cavities for entrapping water. The combined effects of stronger intermolecular interactions and the network induced a higher WHC of the gel with heavier SA. It is interesting to understand the gelling mechanism for the protein-polysaccharide system and to efficiently select SA for developing low-fat meat products in industry.

Biofilms growing on copper and stainless steel substrata in natural drinking water were investigated. A modular pilot-scale distribution facility was installed at four waterworks using different raw waters and disinfection regimes. Three-month-old biofilms were analysed using molecular biology and microscopy methods. High total cell numbers, low counts of actively respiring cells and low numbers of cultivable bacteria indicated the high abundance of viable but not cultivable bacteria in the biofilms. The expression of the recA SOS responsive gene was detected and underlined the presence of transcriptionally active bacteria within the biofilms. This effect was most evident after UV disinfection, UV oxidation and UV disinfection with increased turbidity at waterworks compared to chemically treated and non-disinfected systems. Furthermore, live/dead staining techniques and environmental scanning electron microscopy imaging revealed the presence of living and intact bacteria in biofilms on copper substrata. Cluster analyses of DGGE profiles demonstrated differences in the composition of biofilms on copper and steel materials.

We present data on two prehistoric freshwater mussel (Unionidae) shell assemblages from Bayou Bartholomew, a free-flowing stream in Drew County, southeast Arkansas. The Taylor (3DR2) and Tillar Farms (3DR30) sites provided large shell samples from Baytown (seventh century A.D.) and Mississippian (fifteenth century A.D.) contexts, respectively. Comparison between prehistoric and modern assemblages shows some negative effects on fauna from increased turbidity, a phenomenon that may have begun in prehistoric times. In general, however, despite decades of intensive agriculture and other landscape modifications in the area, historical impacts on molluscan faunas in the Bayou have been unusually minor as compared to other waterways in eastern North America. These data emphasize the value of zooarchaeological remains as they pertain to modern landmanagement issues.

The aim of this work was to perform a preliminary multielemental research of water of Batllava artificial Lake (Kosovo), the main source of potable water for the city of Prishtina and surroundings, using ICP-MS method. Besides that, physico-chemical parameters were determined. From obtained data a detailed assessment of water quality was performed. From physico-chemical parameters turbidity (8.0–17 NTU) and chemical consumption of KMnO4 (79.02–110.62 mgdm− 3) significantly exceed in all samples allowed WHO limits for drinking water, what might be a sign of anthropogenic environmental pollution. Boxplot statistical method performed on Na, Mn, Fe, Co, Ni, Cu, Zn and Pb showed that only Zn has one extreme value (125 µgdm− 3) and this is assumed to be of natural origin. According to concentrations of Cu, Zn, Cd, Cr, Ni and Pb, which are compared with Croatian legislation for surface freshwaters, water of Batllava Lake is rather clean, as all metals on all stations, except Zn on one station, belong to either I, II or III category. Only Fe has on three locations concentrations slightly higher than recommended WHO standard for drinking water (300.00 µgdm− 3), what could be due to lithology of this part of Kosovo. Even situation with water quality of Batllava Lake is overall rather good, establishing of regular monitoring could be advised, especially with respect to iron, zinc and increased turbidity of water. Also, a slight treatment of Batllava Lake water is advised prior to human use, especially in terms of eliminating of present particles from water and lowering of Fe-content.

Two peptides, [f135–158] and [f135–162]-SH, were used to study the binding of the peptides to native ß-lactolobulin, as well as the subsequent effects on aggregation and gelation of ß-lactoglobulin. The binding of the peptide [f135–158] to ß-lactoglobulin at room temperature was confirmed by SELDI-TOF-MS. It was further illustrated by increased turbidity of mixed solutions of peptide and protein (at pH 7), indicating association of proteins and peptides in larger complexes. At pH below the isoelectric point of the protein, the presence of peptides did not lead to an increased turbidity, showing the absence of complexation. The protein–peptide complexes formed at pH 7 were found to dissociate directly upon heating. After prolonged heating, extensive aggregation was observed, whereas no aggregation was seen for the pure protein or pure peptide solutions. The presence of the free sulfhydryl group in [f135–162]-SH resulted in a 10 times increase in the amount of aggregation of ß-lactoglobulin upon heating, illustrating the additional effect of the free sulfhydryl group. Subsequent studies on the gel strength of heat-induced gels also showed a clear difference between these two peptides. The replacement of additional ß-lactoglobulin by [f135–158] resulted in a decrease in gel strength, whereas replacement by peptide [f135–162]-SH increased gel strength.

International audience; We adopt a trait-based approach to explain Diel Vertical Migration (DVM) across a diverse assemblage of planktonic copepods, utilizing body size as a master trait. We find a reproducible pattern of body size-dependence of day and night depths occupied, and of DVM. Both the smallest surface-dwelling and the largest deeper-dwelling copepods refrain from migrations, while intermediate-sized individuals show pronounced DVM. This pattern apparently arises as a consequence of size-dependent predation risk. In the size classes of migratory copepods the amplitude of DVM is further modulated by optical attenuation in the ocean water column because increased turbidity decreases encounter rates with visually hunting predators. Long-term changes in the ocean optical environment are expected to alter the vertical distributions of many copepods and thus to affect predator-prey encounters as well as oceanic carbon export.

Enterococci concentrations in seawater samples collected in 2010 at a Gulf Coast beach in the afternoon were significantly lower (12 MPN/100 mL) compared with morning samples (172 MPN/100 mL). The factors affecting temporal differences of enterococci concentration in beach waters were studied through five laboratory experiments analyzing beach sands, solar radiation, salinity, and turbidity. Enterococci were found in beach sands at a geometric mean of 43 MPN per 100 g of sand, demonstrated the ability to persist for extended periods of time, and increased when incubated (geometric mean of 54 MPN per 100 g sand). Solar radiation inactivated large enterococci concentrations (≥24,196 MPN/100 mL) in as little as four hours in salinities ranging from 0 to 25 parts per thousand (ppt). Increased turbidity (70 and 140 NTU) hindered the effect of solar radiation, suggesting that near-shore turbidity may promote higher enterococci concentrations. The results indicate that enterococci replenishment alo...

The potential benefits and mechanism of explosive explosion shockwave pretreatment on sludge dewatering treatments were investigated in this study. Water content of sludge cake after centrifugation was used to evaluate sludge dewaterability. Particle size, viscosity, turbidity, and micrograph were determined to explain the observed changes in the pretreatment process. The results indicated that the optimal pretreatment condition, generating the lowest water content of sludge cake, was 25 g explosive and 96.7% original sludge water content. This condition resulted in the reduced particle size and viscosity as well as increased turbidity. Particle size and viscosity significantly contributed to enhance sludge dewaterability. Micrograph investigation indicated that explosive explosion shockwave pretreatment could rupture sludge flocs, release physically bound water, and extracellular substances into the solution, consequently enhancing sludge dewaterability.

This paper aims to assess water quality of Danube River in Serbia for 2010. Two methodologies were applied for this purpose: Serbian Water Quality Index (SWQI) and Canadian Water Quality Index (CWQI). WQI value is dimensionless, single number ranging from 0 to 100 (best quality) derived from numerous physical, chemical, biological and microbiological parameters. SWQI was mainly good and very good. This methodology includes parameters for assessment of organic loading, but does not involve parameters of heavy metals concentration. For that purpose CWQI was used. Besides overall, CWQI was calculated for following uses: aquatic habitat, drinking, recreation, irrigation and livestock. Overall CWQI was marginal and fair, which was equivalent with poor and good SWQI. CWQI methodology showed increased concentration of copper in all cases which affected overall water quality and aquatic habitat while increased turbidity in many cases had negative influence on drinking water. Differences between SWQI and CWQI resulted from different methodology: different methods of calculation and parameters. In order to get more comparable results it is necessary to develop unique WQI methodology. [Projekat Ministarstva nauke Republike Srbije, br. 47007]

– The aquatic environment is being perturbed globally through increases in turbidity, which can have detrimental effects for the maintenance of fish diversity, especially in species dependent on visual cues for reproduction and species recognition. We performed a short-term manipulation of the visual environment in Lake Malawi to test for an immediate behavioural response to increased turbidity in territorial rock-dwelling cichlid fishes that use colourful visual cues to maintain territories near the substrate and attract mates. We found a significant movement of fish away from the substrate, with a concomitant shift from displaying territorial and courting behaviours to foraging behaviours, during the five minutes following the release of a turbidity plume over the area. This study is the first to test for and demonstrate an immediate behavioural response of a natural fish population to a short-term increase in turbidity that might mimic the initial (i.e., immediate) stage of a run-off event after rainfall in a deforested area.

The effect of increased turbidity levels on aquatic organisms is an increasing concern for aquatic biologists. Recent studies show reduced foraging efficiency of drift-feeding fish species, which are highly visual predators, with increasing water turbidity. Similar to fish, many aquatic turtle species are highly visual aquatic predators that may be negatively affected by increasing water turbidity. We used Eastern Painted Turtles (Chrysemys picta) to test the hypothesis that increasing water turbidity would decrease prey capture efficiency. We classically conditioned eight C. picta to search for a food item when presented with a novel stimulus, and then measured the time it took each turtle to find a prey item under a range of 26 turbidity levels (≤40 nephelometric turbidity units, NTUs) presented in a random order. All turtles were successfully trained within 29 days to search for the food item when presented with the stimulus. Turbidity had no effect on the probability of successful prey captur...

Experiments done in aquaria under control and either turbid or densely vegetated conditions indicated that three-spined stickleback Gasterosteus aculeatus sneaking behaviour is affected by decreased underwater visibility. Success of sneaking behaviour decreased significantly under increased turbidity but not increased vegetation density. The total number of sneaking attempts, including unsuccessful ones, was not affected by either form of decreasing visibility.

Experiments were conducted to test the effects of turbidity (10–50 NTU) and light (0–2 μE m−2 s−1) on the feeding efficiency of white bream Abramis bjorkna preying on Chaoborus flavicans. Increased turbidity and low light levels did not have a significant impact on the feeding of white bream. In total darkness feeding was impeded indicating that white bream depends on vision for feeding. The dominance of white bream in temperate eutrophic lakes could be attributed to their success of feeding in turbid and low light environments.

© 2015, Springer-Verlag Berlin Heidelberg. Increasing turbidity in streams and rivers near human activity is cause for environmental concern, as the ability of aquatic organisms to use visual information declines. To investigate how some organisms might be able to developmentally compensate for increasing turbidity, we reared guppies (Poecilia reticulata) in either clear or turbid water. We assessed the effects of developmental treatments on adult behavior and aspects of the visual system by testing fish from both developmental treatments in turbid and clear water. We found a strong interactive effect of rearing and assay conditions: fish reared in clear water tended to decrease activity in turbid water, whereas fish reared in turbid water tended to increase activity in turbid water. Guppies from all treatments decreased activity when exposed to a predator. To measure plasticity in the visual system, we quantified treatment differences in opsin gene expression of individuals. We detected a shift from mid-wave-sensitive opsins to long wave-sensitive opsins for guppies reared in turbid water. Since long-wavelength sensitivity is important in motion detection, this shift likely allows guppies to salvage motion-detecting abilities when visual information is obscured in turbid water. Our results demonstrate the importance of developmental plasticity in responses of organisms to rapidly changing environments.

Contrast degradation theory predicts that increased turbidity decreases the visibility of objects that are visible at longer distances more than that of objects that are visible at short distances. Consequently, turbidity should disproportionately decrease feeding rates by piscivorous fish, which feed on larger and more visible prey than particle-feeding planktivorous fish. We tested this prediction in a series of laboratory feeding experiments, the results of which indicated that prey consumption by two species of planktivorous fish (juvenile chum salmon (Oncorhynchus keta) and walleye pollock (Theragra chalcogramma)) is much less sensitive to elevated turbidity than piscivorous feeding by sablefish (Anoplopoma fimbria). Planktivorous feeding in the turbidity range tested (0–40 nephelometric turbidity units (NTU)) was reduced at high light intensity, but not at low light intensity. Comparatively low (5–10 NTU) turbidity decreased both the rate at which sablefish pursued prey and the probability of successful prey capture. These results suggest that turbid environments may be advantageous for planktivorous fish because they will be less vulnerable to predation by piscivores, but will not experience a substantial decrease in their ability to capture zooplankton prey.

The effects of dimethylarsinic acid (DMAA) on microtubule assembly in vitro were investigated in terms of the role of glutathione (GSH). Increase in turbidity due to assembly of brain tubulins was monitored in the presence or absence of DMAA. DMAA at concentrations up to 10 mM did not cause inhibition of the increased turbidity. GSH at concentrations over 10 mM enhanced the increase in turbidity. By contrast, the increased turbidity was inhibited markedly when DMAA and GSH were combined in the ratio of 5:1. Moreover, the combination similarly inhibited calcium-induced disassembly of microtubules with a potency equivalent to that of 10 μM taxol. These results suggest that DMAA inhibited not only microtubule assembly, but also calcium-sensitive disassembly of microtubules, via interaction with GSH.

– Two different Denil fishways on the Grand River, Ontario, were used as check-points to evaluate the upstream movement of fishes past a low-head weir and to examine the proportions and inferred swimming performance of non-salmonid warmwater fishes that used each fishway type. Traps installed at fishway exits were used to collect fish during 24-hour sampling periods, over 40–51 days each year, from 1995 to 1997. Passage rates, size selectivity, water temperature, water velocity and turbidity for the periods of maximum passage for each year were examined. General species composition from trap samples shifted from catostomids to cyprinids to ictalurids to percids and centrarchids, with some overlap, as water temperatures increased from 8 °C to 25 °C in the spring and early summer. Water depths, and therefore water velocities in each fishway, were independent of river discharge due to variable accumulations of debris on upstream trash-racks. Relationships between the water velocity and the swimming and position-holding abilities of several species emerged. Turbidity was directly related to river discharge and precipitation events, and many species demonstrated maximum fishway use during periods of increased turbidity. This study 1) provided evidence of strongly directional upstream movements among several species that were previously considered non-migratory and 2) describes physical and hydraulic conditions during fishway use for 29 non-salmonid fish species.

Effects of ethanolic coconut husk extract (ECHE) at various levels (0–0.03%, based on protein content) on the heat-induced aggregation of natural actomyosin (NAM), extracted from sardine (Sardinella albella) muscle, were studied. During heating from 20 to 90C, the NAM solution showed increased turbidity, surface hydrophobicity, and disulfide bond content. Aggregation was more pronounced as ECHE concentration increased (P

[1] Storm-driven flow pulses in rivers destroy and restructure sediment habitats that affect stream metabolism. This study examined thresholds of bed disturbances that affected patch- and reach-scale sediment conditions and metabolism rates. A 4 year record of discharge and diel changes in dissolved oxygen concentrations (ΔDO) was analyzed for disturbances and recovery periods of the ΔDO signal. Disturbances to the ΔDO signal were associated with flow pulses, and the recovery times for the ΔDO signal were found to be in two categories: less than 5 days (30% of the disturbances) or greater than 15 days (70% of the disturbances). A field study was performed during the fall of 2007, which included a storm event that increased discharge from 3.1 to 6.9 m3/s over a 7 h period. During stable flow conditions before the storm, variability in patch-scale stream metabolism values were associated with sediment texture classes with values ranging from −16.4 to 2.3 g O2/m2/d (negative sign indicates net respiration) that bounded the reach-averaged rate of −5.6 g O2/m2/d. Hydraulic modeling of bed shear stresses demonstrated a storm-induced flow pulse mobilized approximately 25% of the bed and reach-scale metabolism rates shifted from −5 to −40 g O2/m2/d. These results suggest that storm-induced bed disturbances led to threshold behavior with respect to stream metabolism. Small flow pulses resulted in partial-bed mobilization that disrupted stream metabolism by increased turbidity with short recovery times. Large flow pulses resulted in full-bed mobilization that disrupted stream metabolism by destroying periphyton habitats with long recovery times.

When drinking water is distributed through pipelines, biofilms will grow on the inner surface of the pipes and soft deposits (organic and inorganic matter) and several metals will accumulate to the pipelines (Lehtola & al, 2004a). Discoloration of drinking water is one of the main reasons customers complain to their water company. An elevated concentration of iron or increased turbidity, affect taste, odor and color in drinking water. Unlined iron pipes in drinking water distribution networks develop extensive internal corrosion scales as the time of use increases. These corrosion scale deposits reduce the hydraulic capacity of the pipes and more energy is required to deliver water at a desire flow rate (Sarin et al., 2004).

Silts, present in sand extraction sites, can potentially mobilize in the water column and result in increased turbidity of the North Sea. The main knowledge gap in assessing this potential risk is the capacity to buffer silts in the sandy sediments. To assess this buffering potential, Rijkswaterstaat and Stichting LaMER started a Monitoring and evaluation program (MEP Sandmining) to monitor, amongst others, the concentration and variation of fines in the sediments off the Dutch Coast. We monitored the concentration of fines in the sediment along 3 cross-shore tracks, ranging from 0-9 km off the coast, with the Medusa system and by taking sediment samples. The Medusa system results in continuous measurements of the silt content of sediments along a line, the samples have been used for validation purposes. In the period September 2009 - Oktober 2010, 6 campaigns have been conducted. Measurements show that, although the silt content is very low (

The compatibility of piperacillin sodium plus tazobactam with selected drugs during simulated Y-site administration was studied. A 5-mL sample of piperacillin sodium 40 mg/mL plus tazobactam 5 mg/mL (Zosyn) in 5% dextrose injection was combined with a 5-mL sample of each of 75 other drugs at concentrations used clinically. Each combination was prepared in duplicate in glass culture tubes, with the order of mixing being reversed between the duplicates; storage was in constant fluorescent light at 22 degrees C. The admixtures were examined visually in normal fluorescent light and in high-intensity light zero, one, and four hours after preparation. A turbidimeter was used to measure the turbidity of each drug combination at the same intervals. Samples showing visual or turbidimetric evidence of incompatibility were subjected to particle sizing and counting. The majority of the drugs tested were compatible with Zosyn injection; most combinations had a turbidity of less than 0.1 nephelometric turbidity unit. However, 24 drugs exhibited various incompatibilities, including increased turbidity, particulate formation and precipitation, and color change. Piperacillin sodium 40 mg/mL plus tazobactam in 5% dextrose injection was visually compatible with the majority of the drugs tested for up to four hours at 22 degrees C but incompatible with 24 drugs.

Purpose The physical compatibility of ceftaroline fosamil with commonly used medications and diluents (a total of 73 drugs in 219 admixtures) during simulated Y-site administration was evaluated. Methods Duplicate 5-mL samples of ceftaroline fosamil (2.22 mg/mL) in 5% dextrose injection, 0.9% sodium chloride injection, and lactated Ringer’s injection were combined at a 1:1 ratio with samples of 73 drugs (diluted or undiluted). Visual examinations were performed with the unaided eye in fluorescent light and with the aid of a Tyndall beam; the turbidity and particulate content of each sample were also measured. The compatibility of ceftaroline fosamil with propofol was evaluated by visually inspecting for emulsion separation and particle formation after centrifugation. All evaluations were performed within 15 minutes of sample preparation and at one and four hours after preparation. Results Ceftaroline fosamil was physically compatible with 64 drugs in a combination of 196 admixtures for at least four hours, exhibiting color, clarity, turbidity, and microparticle content similar to those of control solutions. Signs of physical incompatibility, including visible precipitation, increased turbidity, and microparticle formation, were observed with 9 drugs in 23 admixtures during the four-hour observation period. Conclusion Of the 73 drugs evaluated, 64 were compatible and 7 were incompatible with ceftaroline fosamil 2.22 mg/mL in 3 standard infusion solutions. Nine drugs in 23 admixtures were observed to exhibit signs of incompatibility with ceftaroline fosamil within four hours of mixing; those drugs should not be simultaneously administered via a Y-site with ceftaroline preparations.

The Mahavavy-Kinkony wetland complex is an ecologically diverse and economically critical habitat assemblage. Despite recently receiving national protection, the ecological integrity of Lake Kinkony is threatened by the conversion of adjacent, unprotected lands into rice paddies. Conversion to aqua-cultural lands eliminates reed beds which provide favoured habitat for numerous endemic and endangered avian, fish and reptilian species, including Amaurornis olivieri , Paretroplus dambabe , P. kieneri and Erymnochelys madagascariensis . This research identified the physio-chemical sources and extent of degradation and evaluated the associated impacts on endangered wildlife. Employing digital environmental data within a Geographic Information System, the historical extent of reed habitat (circa 1949) was compared to distribution identified through fieldwork in 2008, indicating an areal loss of 80%. Results indicate the primary contributor to reed loss was increased turbidity associated with erosion. The continuing decrease in marsh habitat facilitated by an increase in erosion poses significant threats to already endangered wildlife. However, while the reduction in marsh area was shown to reduce habitat availability for Amaurornis olivieri , observations imply this species does not occupy all potential reed habitats and that territorial preferences and tolerance towards turbidity need to be understood to accurately determine the magnitude of threat. Despite the need for continued research, information representing agents of change and their associated ramifications on fauna is essential for developing regional conservation and natural resource management strategies. In particular, anti-erosion management of the most vulnerable water catchment areas and restoration activities within the most severely degraded marshes are prescribed. RESUME Le lac Kinkony fait partie des habitats clefs pour la biodiversite du Complexe des Zones Humides Mahavavy-Kinkony, une des Nouvelles Aires Protegees prioritaires qui doit etre mise en place a Madagascar. Malgre les pressions anthropiques comme la conversion des zones marecageuses en rizieres et la surpeche qui s’exercent sur le lac, le lac joue un role economique et ecologique important dans la region. La presente recherche a permis d’identifier les changements physico-chimiques importants de ce biotope lacustre afin d’evaluer les menaces qui pesent sur sa faune afin de fournir aux decideurs les elements necessaires a l’elaboration des strategies de conservation de ses ressources biologiques. Les analyses ont ete basees sur l’utilisation des outils d’investigation spatiale comme le Systeme d’Information Geographique et la Teledetection, appliquees plus particulierement sur le lac Kinkony, a savoir le plan d’eau et les zones de phragmites de son pourtour marecageux. Les resultats obtenus, nous ont permis d’estimer une forte reduction de la superficie occupee par les phragmites, de l’ordre de 80% entre 1949 et 2008. Les principales sources de sediments qui contribuent a la turbidite de l’eau du lac proviennent de l’erosion des bassins versants situes au Sud du lac. Les depots apportes par les rivieres au cours des temps ont provoque l’envasement du lac et la reduction progressive de la profondeur des zones d’entree, au niveau de la confluence du plan d’eau avec ces rivieres. La reduction de la superficie des phragmitaies couplee a l’erosion constituent ainsi les principales menaces ecologiques qui affectent le lac Kinkony. Si l’evaluation precise du degre d’impact de ces changements et leur eventuelle synergie sur la biologie de la faune menacee requierent de plus amples recherches, des amenagements anti-erosifs sur les quatre bassins environnants les plus vulnerables et des restaurations de phragmitaies sont proposes pour la conservation de la biodiversite du lac Kinkony.

Immunomagnetic separation (IMS) has been specified as a standard method for the measurement of Giardia under USEPA Method 1623. In this study, IMS was evaluated on the basis of recovery efficiencies for Giardia cysts under various IMS operation conditions. Significant change in recovery was observed by altering the debris ratio of water samples. Notably, cyst recovery efficiencies utilizing IMS dropped with increased turbidity, and results for varying dosages of magnetic beads and cysts indicate that 1 / 100 immunomagnetic beads is sufficient to conjugate large numbers of cysts. Changing vessel volume and replacing the sample buffer had no significant effect on cyst recovery efficiencies.

LATEST DEVELOPMENTS IN SMALL HYDRAULIC DREDGES FOR CONTAMINATED SEDIMENT REMOVAL IN THE USA Eric H. Seagren Abstract: The use of small hydraulic dredges actually began in the early 70’s with the introduction of the horizontal auger dredges for lake dredging in Minnesota..Testing performed during the Dredge Material Research Program-USACE in the late 70’s showed that small hydraulic dredges , both basket cutterhead and horizontal auger units were excellent for contaminated sediment removal when used correctly under specific site conditions. This led to the dredging of numerous water supply lakes, and the EPA found that these lakes could remain in service as a drinking water supply during actual dredging operations. Unfortunately, these smaller dredges were placed in coastal environments and rivers and they did not live up to the results found in calm waters. Wind action, river currents, and tide changes prevented accurate positioning , and some of the material was hard to dredge. These items combined caused increased turbidity and material was left behind. This paper will discuss the advancements made in the small dredging field ( four inch to twelve inch pump discharge diameters ) over the past 30 years in horizontal auger, cutterhead, swinging ladder, lagoon pumpers and specialty dredges. In all of the latest advancements, the control of turbidity is of critical concern for many reasons, the most important being the well being of the water borne environment and man’s use of its resources. Turbidity is defined as the re-suspension of the bottom sediments back into the water column which appear sometimes as a “plume” in the water or the increase in turbidity in the surrounding waters above residual or “background levels” Contaminated sediment removal using environmentally sensitive dredging machinery is on the increase and the water bodies in place must be preserved. There are currently over 50 dredging applications which require contaminated sediment removal and the number is on the increase. Dredge selection is the most critical portion of a given project once the site parameters are known, especially the material to be dredged. The attendee will be better prepared to select the proper dredge for a given project and not rely on a single manufacture’s recommendation.

A rapid estimate of wax content in sunflower seed oil may be obtained by heating the oil to 130 C and subsequent cooling in ice for 10 to 15 min. Microcrystalline waxes are then formed. They are quantified by measuring increased turbidity with a sensitive turbidity meter. Calibration is made with thoroughly dewaxed oil to which known amounts of wax are added, and the turbidity increase is determined after 10 minutes at 0 C. The method has been compared with modified cold test, comprising visual inspection after 24 hours at 0 C and after 5 days at 20 C. The rapid tubidimetric method is superior to cold test in predicting the tendency of oils to precipitate small amounts of wax after long-time storage.

Migration of smolts in the River Piddle, Dorset, was studied over three years in relation to factors that could influence downstream movement. The river originates mostly from groundwater springs, resulting in stable flows and low turbidity except in very rainy weither. Fish were intercepted at the tidal limit in a fixed trap-net, and measurements of water temperature, discharge, turbidity, barometric pressure, rainfall and solar radiation taken nearby. Slightly increased turbidity and discharge following heavy rain initiated major movements during two nights of the total of 55 days studied. At other times large-scale movements rock place during sunny warm afternoons. Both solar radiation and water temperature were correlated with intensity and timing of movement. The pattern of migration is different from that reported on other rivers, reflecting the relatively stable flow regime of the chalkstream.

The spread and abatement of the aerosol injected into the stratosphere by the explosion of Katmai volcano in Alaska on June 6, 1912, have been investigated. The spread of the dust veil and twilight observations are discussed. Turbidity was determined from solar radiation data obtained mainly in central and northern Europe and the United States. In Europe, volcanic turbidity was quite large but highly variable during the summer of 1912 and became rather low in February 1913, when it was still high over the United States. Temporary presence of Katmai dust over Mexico City is very questionable, so that increased turbidity over Peru during 1913 may have had other causes. The turbidity disappeared rather suddenly in late 1914. Average residence time of the dust was nearly 1 year.

Eggs of herring ( Clupea harengus ), artificially fertilized in the laboratory, were exposed either to different constant concentrations of suspended silt (about 5–300 mg l −1 ) or to a short-term high concentration (500 mg l −1 ) at different times during embryonic development. These experiments were made to test the effect of the increased turbidity near marine mining, spoil disposal or dredging operations. Embryonic development was unaffected by suspended silt. Mortality rates varied significantly between aquaria, but the variation was unrelated to the experimental treatment with silt. It is thus concluded, that, as far as the suspended particles are concerned, no harmful effects of dredging and similar operations to herring spawning grounds are likely to occur.

An underwater camera system was designed to record the behavior of male nest-guarding longear sunfish (Lepomis megalotus) during periods of boating activity. Boats traveling at slow speeds near nests usually drove males from their nests, increasing the likelihood of egg predation. Boats moving at higher speeds or further from nests caused little or no displacement of males, but increased turbidity and possible success of predators. Location of a nest near cover increased the male's ability to protect his nest during repeated surface disturbances.

30 women (24-34 years; parity 3-6) randomly selected from the family planning clinic at Al-Azhar University Hospital, Cairo, were divided into 3 groups: 1) 10 normal fertile; 2) 10 women fitted with T-Cu-200 for 2-20 months; and 3) 10 women fitted with Lippes loop for 2-8 years. On the 13th-15th day of the cycle cervical mucus was sample and tested for sperm penetration, motility, turbidity, Spinnbarkeit, and ferning. Sperm penetration tests used the sperm migration meter of Kremer and turbidity and clarity were assessed by the naked eye. Sperm penetration and motility were greatly impaired with Cu-device users, while with Lippes loop the findings approached that of the normal control women. Turbidity results were significant (p less than .01) for Cu-device users. Diminished Spinnbarkeit and positive ferning were also observed in the presence of the Cu device. The impaired sperm penetration and immobilization with the use of the Cu-devices as opposed to Lippes loop suggests a local lethal effect of the increased copper on cervical mucus rather than a local foreign body reaction.