Intake Screens Research Articles

Documenting limited health literacy in a clinical setting.

Health literacy is important in lung cancer care, where treatments and symptoms are difficult to navigate. This study aims to describe how a single-item measure of health literacy can facilitate health literacy system capacity. Data include retrospective medical records from 456 patients with lung cancer. Limited or adequate health literacy was based on participant response to the Single Item Literacy Screener (SILS). Data were collected over a 12-month period following diagnosis for each patient. One-third of patients had limited health literacy; they were more likely to have lung cancers of stage IIIB or higher and greater median levels of depression based on the PHQ-9 questionnaire. Patients with limited health literacy were also more likely to have at least one emergency department visit or unplanned hospitalization and had these visits sooner. These data document need for interventions to buffer the association between limited health literacy and poor health outcomes. Routine intake screens should include the SILS to measure health literacy among lung cancer patients. New models that address health literacy at the organizational and patient levels can be implemented in health care settings using the SILS.

Lindavia intermedia (Bacillariophyceae) and Nuisance lake Snow in New Zealand: Chitin Content and Quantitative PCR Methods to Estimate Cell Concentrations and Expression of Chitin Synthase1.

Lake snow, caused by the freshwater centric diatom Lindavia intermedia, has become problematic in several large, oligotrophic New Zealand lakes over the past decade. Macroaggregates produced by L.intermedia foul fishing lines, intake screens, and water filters, and have a negative impact on recreational values. It was confirmed that the fibers constituting lake snow are composed of chitin, two chitin synthase genes (chs1 and 2) from L.intermedia were characterized, new qPCR-based tools to quantify the abundance of the species and measure expression of chs2 relative to the reference gene act1 (the product of which has cytoskeletal functions) were developed. The strong heterogeneity and mucilaginous nature of lake snow samples create particular difficulties for calibrations of gene or transcript copy numbers with cell densities and obtaining high yields of mRNA. However, data collected from four lakes during November 2018 and February and May 2019 show that abundance of L.intermedia is always high when lake snow is also abundant, but that a full range of L.intermedia abundance can occur when lake snow is absent, suggesting that chitin production is not obligate in L.intermedia. This result is consistent with the available data for chs2 expression, which suggest higher transcription when lake snow is abundant. Lake snow production by L.intermedia therefore requires an as yet undetermined stimulus independent of cell abundance.

Design of submerged vane matrices to accompany a river intake in Australia

This paper focuses on the design of river-based submerged vane matrices in a regional Australian context. The specific study site is proximal to intake screens within the riverbed that experiences continual clogging from sediment deposition. The local authority experiences discontinuous supply to the water-treatment plant owing to a high sediment concentration. Data on the river flow, depth, turbidity and rainfall were collected, and analyses of sediment composition, gradation and density were carried out within this research. Through the study of incipient sediment motion and hydraulics, with specific reference to the method of Shields, the shear stress and critical velocity necessary for sediment motion were determined. The results provided guidance for an iterative modelling design of submerged vanes within the local context ultimately configured as symmetrical diverging vane matrices. Placed a short distance upstream of the existing intake screens at a 30° angle to the river flow direction on two symmetric arms, the three vane arrays generate secondary flow as a function of the existing flow around the vanes. The purpose of the vane matrix is twofold, firstly to redirect sediment away from the existing infiltration galleries and secondly to scour the riverbed within the bounds of the matrices. With a subsequent increase in the depth of water, intake screen(s) placed within and orthogonal to the flow would benefit from an increased depth in combination with a reduction in sediment delivery to the screen(s).

Fish behavior and fish guidance at hydropower intake screens for fish downstream passage

Fish behaviour investigations under controlled laboratory conditions but nature like environment were conducted to clarify the efficiency of inclined and horizontal screen planes for fish protection and fish downstream passage at hydropower plants concerning different potamodromous species and various sizes. The dependency on the underlying geometric and hydraulic parameters was investigated and comprehensive models were deduced to describe these relations. Adequate geometric and hydraulic design could achieve high levels of fish protection and downstream passage efficiency, even for small fish, weak swimmers and riverbed/bottom oriented species. The results imply good transferability and accordance with field observations at large scale facilities and can provide valuable information for facility design.

Callinectid Crab Abundances, and Movements of Tagged Blue Crabs (Callinectes sapidus) in the Cape Fear River and Adjacent Waters, North Carolina

A six year (1973-1978) 23 stations survey of the Cape Fear River and the adjacent waters was instituted to determine the effects of the CP&L (now Duke) Brunswick 1,979 MW nuclear power plant on the biota, especially crabs, frequenting the area. Callinetes sapidus, blue crabs, were the most abundant of the five Callinectid crabs collected. Only 180 or 0.5% of tagged C. sapidus were impinged of the power plant intake screens.

Influence of Approach Velocity and Mesh Size on the Entrainment and Contact of a Lowland River Fish Assemblage at a Screened Irrigation Pump

Fish screens can help prevent the entrainment or injury of fish at irrigation diversions, but only when designed appropriately. Design criteria cannot simply be transferred between sites or pump systems and need to be developed using an evidence-based approach with the needs of local species in mind. Laboratory testing is typically used to quantify fish responses at intake screens, but often limits the number of species that can studied and creates artificial conditions not directly applicable to screens in the wild. In this study a field-based approach was used to assess the appropriateness of different screen design attributes for the protection of a lowland river fish assemblage at an experimental irrigation pump. Direct netting of entrained fish was used along with sonar technology to quantify the probability of screen contact for a Murray-Darling Basin (Australia) fish species. Two approach velocities (0.1 and 0.5 m.sec−1) and different sizes of woven mesh (5, 10 and 20 mm) were evaluated. Smaller fish (<150 mm) in the assemblage were significantly more susceptible to entrainment and screen contact, especially at higher approach velocities. Mesh size appeared to have little impact on screen contact and entrainment, suggesting that approach velocity rather than mesh size is likely to be the primary consideration when developing screens. Until the effects of screen contacts on injury and survival of these species are better understood, it is recommended that approach velocities not exceed 0.1 m.sec−1 when the desire is to protect the largest range of species and size classes for lowland river fish assemblages in the Murray-Darling Basin. The field method tested proved to be a useful approach that could compliment laboratory studies to refine fish screen design and facilitate field validation.

Managing a Surface Water Supply to Meet Future Needs

This article discusses a project by Tampa Bay Water to expand the Tampa Bypass Canal Pump Station's capacity to improve the utility's surface water supply system. The project expanded the pump station's capacity from 138 mgd to 259 mgd and a repump station from 128 mgd to 185 mgd to collect and store water and supply the surface water treatment plant at a regional facility. The pump station withdraws available surface water from two segments of the bypass canal and transfers it to the repump station, which pumps the water to the reservoir or the surface water treatment plant. This article focuses on the bypass canal pump station, particularly site selection; operating conditions; expansion design, including capacity alternatives and intake screens; and construction.

Validation of Brief Screening Tools for Mental Disorders Among New Zealand Prisoners

This study aimed to validate brief intake screens for serious mental illnesses among New Zealand male prisoners. A prospective survey of consecutively admitted male remanded and sentenced prisoners was conducted across two New Zealand sites. Participants completed the Brief Jail Mental Health Screen (BJMHS) and the English Mental Health Screen (EMHS) upon prison admission. The validation standard, the Mini International Neuropsychiatric Interview (MINI), was completed for all positive screens and a random selection of negative screens. A total of 1,292 brief screens and 530 MINI screens were completed. Fifty-one percent of the participants met MINI criteria for one of five targeted major mental disorders. In this study, the BJMHS performed with lower sensitivity, higher specificity, a lower false-positive rate, a significantly higher false-negative rate, and a much higher referral rate than in the validating U.S. study. And in this study the EMHS performed with lower sensitivity, less specificity, higher false-positive and false-negative rates, and a moderately higher overall referral rate than in the validating U.K. study. For the BJMHS and EMHS, the majority of false-negative cases involved a mood disorder and few involved psychosis. Although the BJMHS and EMHS did not perform well in terms of screening for MINI diagnoses, they appeared to be good at identifying a core group of prisoners who are psychotic and most likely to require urgent or semi-urgent intervention by mental health services. The most favorable clinical outcomes were achieved by defining a positive screen as one in which either the EMHS or the BJMHS criteria were fulfilled.

Multispecies impingement in a tropical power plant, Straits of Malacca

Marine organisms comprised about 70% of the total impinged materials by weight at water intake screens in the Kapar Power Station (KPS), Malaysia. The general groupings of ‘fish’, ‘shrimp’, ‘crab’, ‘cephalopod’ and ‘others’ contributed 26% (87 species), 65% (29), 2% (17), 2% (3) and 5% (42) of the total number of impinged organisms, respectively. In general, higher impingement occurred during spring tide, at nighttime and in shallow water. The glass perchlet, anchovies, ponyfishes, mojarra, catfishes, hairtail, scat and young croakers were the most vulnerable fishes. Vulnerable invertebrates included cephalopods, sea urchin, rockshells and jellyfishes, but penaeid shrimps were the most susceptible in terms of both mortality and body injury. Annually, KPS is estimated to kill 8.5 × 10 6 marine organisms (42 tons) by impingement. This amount, however, is minimal compared to commercial fishery harvests. Multispecies impingement at Malaysian power plants poses the problem of finding the best mitigation options for tropical situations.

Long-term changes in fish-assemblage composition from cooling-water intake screens in the Forth Estuary, Scotland, UK

Changes in the composition of fish assemblages collected on two closely located power stations' intake screens over nearly four decades in the middle Forth Estuary, Scotland were examined. There were no significant differences in fish assemblages from Kincardine in 1979 and 1961–1962 or between Longannet in 1979 and 1994. Otherwise, the 1979 assemblages from both locations were significantly different from the 1999 and 2000 Longannet assemblages and from each other. The long-term differences may have reflected local environmental changes, notably a considerable increase in smelt ( Osmerus eperlanus ) abundance due to improved water quality, and declines in some species (eelpout ( Zoarces viviparous ) and cod ( Gadus morhua )) because of regional environmental influences such as increases in water temperature and overfishing.

Eichhornia crassipes

<i>Eichhornia crassipes</i>

Fish mortality by impingement on the cooling-water intake screens of Britain’s largest direct-cooled power station

An estimated 5.66 × 10 7 fish (summed quarterly 95% confidence intervals: 3.01 × 10 7–1.07 × 10 8) weighing 258.4 t (143.2–467.9 t) were killed on the cooling-water intake screens of the 2400 MW Longannet Power Station (Forth estuary) in January 1999–December 2000. Abundance and number of species (40) collected were close to predictions for a power station of this size and latitude. Potential losses of equivalent adult whiting ( Merlangius merlangus), cod ( Gadus morhua), and plaice ( Pleuronectes platessa) through deaths of juveniles were estimated at 353.1 t (208.0–603.2 t) worth approximately €429,266 (€246,592–752,765) in 1999–2000. Fish catch-per-trawl in the estuary was generally not noticeably greater during a year of low water withdrawal (coal miners’ strike of 1984–1985) when compared to other years from 1982 to 2001, except for gobies ( Pomatoschistus spp.). A fish-return system is being tested at Longannet to reduce mortality.

Anthropogenic causes of jellyfish blooms and their direct consequences for humans: a review

Although recent articles state that jellyfish populations are increasing, most available evidence shows that jellyfish abundances fluctuate with climatic cycles. Reports of increasing prob- lems with jellyfish, especially in East Asia, are too recent to exclude decadal climate cycles. Jellyfish are infamous for their direct negative effects on human enterprise; specifically, they interfere with tourism by stinging swimmers, fishing by clogging nets, aquaculture by killing fish in net-pens and power plants by clogging cooling-water intake screens. They also have indirect effects on fisheries by feeding on zooplankton and ichthyoplankton, and, therefore, are predators and potential competitors of fish. Ironically, many human activities may contribute to increases in jellyfish populations in coastal waters. Increased jellyfish and ctenophore populations often are associated with warming caused by climate changes and possibly power plant thermal effluents. Jellyfish may benefit from eutrophication, which can increase small-zooplankton abundance, turbidity and hypoxia, all conditions that may favor jellyfish over fish. Fishing activities can remove predators of jellyfish and zooplanktivorous fish com- petitors as well as cause large-scale ecosystem changes that improve conditions for jellyfish. Aquacul- ture releases millions of jellyfish into Asian coastal waters yearly to enhance the jellyfish fishery. Aquaculture and other marine structures provide favorable habitat for the benthic stages of jellyfish. Changes in the hydrological regime due to dams and other construction can change the salinity to favor jellyfish. Accidental introductions of non-native gelatinous species into disturbed ecosystems have led to blooms with serious consequences. In many coastal areas, most of these environmental changes occur simultaneously. We summarize cases of problem jellyfish blooms and the evidence for anthropogenic habitat disruptions that may have caused them. Rapid development in East Asia makes that region especially vulnerable to escalating problems. We conclude that human effects on coastal environments are certain to increase, and jellyfish blooms may increase as a consequence.

Trawls and cooling-water intakes as estuarine fish sampling tools: Comparisons of catch composition, trends in relative abundance, and length selectivity

Fish populations in estuaries are often monitored with traditional sampling gears such as trawls. Trawling is relatively expensive and may be hindered by environmental conditions such as tides and substrates. Power station cooling-water intake screens have been effectively used as estuarine fish sampling devices for many years, but very few quantitative comparisons of intake fish-catch characteristics with samples from other collection methods have been made. Fish collected at the cooling-water intake of a large power station in the lower Forth estuary, UK, were more similar in assemblage composition to fish caught by nearby pelagic trawling than to fish caught by Agassiz (demersal) trawling, mostly because the intake and pelagic-trawl catches were largely composed of clupeids ( Sprattus sprattus and Clupea harengus). The intake catch was typified by pelagic, demersal, and benthic species, however, and was less variable than the catches made by the two trawls. Monthly trends in relative abundance correlated reasonably well between the intake and trawl samples. Fish collected at the intake tended to be significantly smaller than those collected by trawling, which was probably attributable to the intake's smaller mesh size. The study highlighted the utility of a cooling-water intake as an efficient, low-cost fish sampling device, which should be considered as an alternative to trawling as the cost of the latter increases into the future.

발전소 취수구에 대량으로 유입하는 해양생물에 대한 스크린 설비의 성능분석

Screening performance of the existing intake screens (drum and travelling screen) on mass impingement of marine animals, a euphausiid, Euphausia pacifica and a scyphozoan medusae, Aurelia aurita that have often clogged intake screens of the Uljin Nuclear Power Plant, was tested. The maximum tolerable densities of marine animals in the inflowing seawater upon the screen were estimated with two different approaches. First, the maximum density of jellyfish was calculated from (1) passing amount of seawater per unit time through the screens and (2) the covered area of animals on the screens clogged. The maximum density of krill tolerable in the drum screen was cited from a simulated record of Uljin NPP, then those in the travelling screens were also calculated using the data of drum screen and ratio of seawater amount passing through the screens under the condition of 0.5 m water column (W.C.) of the differential pressure (?P) produced by screens, an established permissible limit of ?P. Secondly, the screening performances were also tested by hydrodynamic measurements with various screen models in a circulating water channel equipped with a speed-controlling pump and a differential pressure gauge. From the first approach, the maximum tolerable densities of drum and travelling screen were calculated as 2.0 and 1.5 ind/㎥ for the jellyfish and 900 and 680 ind/㎥ for the euphausiid, respectively. These densities estimated from the second approach were 2.1 and 0.8 ind/㎥ for the jellyfish and 1059 and 504 ind/㎥ for the euphausiid, respectively. These estimates were compared with the data from historic clogging events to evaluate the practical performance of these intake screens. The comparisons suggest a newly improved intake-screen of which performance should be at least seven times (approximately) better than the existing ones for the krill and 3.2 times for the jellyfish, respectively, for preventing mass impingement, and for maintaining the condition of the differential pressure between the screens below 0.3 m W.C.

Downstream passage of silver eels at a small hydroelectric facility

Abstract A 100‐mm diameter bypass was installed in the dam face at a small hydropower station on the Mokau River, New Zealand, and its use by downstream migrating silver eels, Anguilla spp., was monitored by trapping at the outlet in autumn 2002 and 2003. In addition, a passive integrated transponder system was used to monitor passage over the spillway. Migrant eels were able to find the bypass, with 544 and 744 eels recorded using it in 2002 and 2003 respectively. Although the bypass was the sole means of safe passage at low flow, migrant eels passed down the spillway in preference to the bypass when the dam was overtopped during floods. A combination of spilling and small diameter bypasses would provide safe downstream passage at hydroelectric facilities for silver eels, so long as entrainment and impingement at the intake screens can be prevented.

Recent invasions of alien macroinvertebrates and loss of native species in the upper Rhine River, Germany

In the summers of 2003-2005 we sampled the macroinvertebrate community of the upper Rhine River at 28 locations between kilometer 351.9 and 399.5 with a dredge and a hydraulic grab from a ship, or by hand sampling. Additionally, 16 samples were obtained from the cooling water intake screens of a thermal power plant in 2003. A total of 133 species and higher taxa were identified from approximately 140,000 organisms. A total of 33 neozoa (alien) species were identified, including the first record of Chelicorophium robustum in the Rhine River. Neozoa contributed approximately 74% to the total number of organisms collected from the ship-based samples and 85% to those from the power plant cooling water. Almost 64% of all individuals from the cooling water intake belonged to the Ponto-Caspian amphipod Dikerogammarus villosus. Similarly, only 13 taxa, four native and nine alien species, numerically dominated in the ship-based samples, representing 95% and 98% of all organisms in 2003 and 2004, respectively. The nine alien species contributed 74.7% and 72.1%, respectively, to the number of organisms. Only six species occurred abundantly in the main channel of the Rhine River, five of which were neozoa: Jaera istri, Dikerogammarus villosus, Dreissena polymorpha, Chelicorophium curvispinum, and Hypania invalida. The six abundant species colonized nearshore substrates, whereas only few species were retrieved at low densities from the bottom gravel of the central shipping lane. Species diversity was generally higher and relative abundance of neozoa was lower in backwater areas than in the main river channel. Some pronounced changes in the abundance of three numerically dominant species, including the neozoa D. polymorpha and C. curvispinum, occurred between 2003 and 2004, which likely correlated with differences in water levels and temperatures. Overall, our results demonstrate that the macroinvertebrate community of the upper Rhine River has been severely altered by the invasion of several highly successful alien species and the disappearance or population decline of native species, and that these processes are still ongoing. Changes in species composition and relative numerical abundance indicate both a displacement of native species by invasive species, and a relative rapid succession in the numerical dominance of “old“ neozoa and “new“ neozoa.

Ecotoxicological marine impacts from seawater desalination plants

During their operation, seawater thermal desalination plants may adversely affect aquatic communities in estuaries by the impingement of organisms on intake screens, the entrainment of various life forms in cooling water systems, the thermal and brines loadings of receiving waters with the release of harmful components containing heavy metals (Cu, Fe, Ni, Cr, Zn), additive substances (anti-scaling, antifouling, antifoaming, anticorrosion) and their conversion products. Desalination plant discharges influence both the water quality and the organisms of impacted estuaries, directly or indirectly with the most acute effects found in the vicinity of the discharge outfalls outlet. Increasing temperature lowers the dissolved oxygen content of receiving waters while raising the metabolism rate of its faunal inhabitants, elicit physiological and behavioural responses in organisms. An increase in salt concentration, which raises the density of waters, fosters stratification of receiving water bodies, can lead to an increase of turbidity, disrupt the photosynthesis process, and disturb the biogenesis, to an extinction of mainly sensitive benthic species, larvae and young individuals. Some of the chemical components released by desalination plants pose a potential hazard to estuarine organisms owing to their toxicity. Most important in this respect are chlorine and trace metals loads which must receive much attention because at times it accounts for much of the mortality of susceptible organisms in discharge waters, leaving their mark on the flora and fauna around the pipeline outlet. The ultimate consequences on estuarine communities of all these physical and chemical parameters of these discharges are shifts in their structure. Changes in species composition, species diversity, and population density are commonly observed in the area of the discharge. In some cases, opportunistic or nuisance species may replace equilibrium populations at heavily impacted sites.

Controlling biofouling caused by the colonial hydroid Cordylophora caspia

The euryhaline hydroid, Cordylophora caspia, causes fouling problems in Europe and the United States. Researchers propose that this hydroid is becoming more prevalent in freshwater habitats as evidenced in Morris, IL where it was found clogging intake pipes and screens at a power plant, Midwest Generation's Collins Station. Our objective was to determine ways to curtail growth or kill C. caspia. Hydroid colonies in the laboratory were exposed to thermal treatments of 35, 36.1, 37.7, and 40.5 °C ranging from 1 to 8 h. Hydroids did not survive at the two highest temperatures. Colonies exposed to lower temperatures exhibited varying degrees of survival relative to temperature and exposure time and demonstrated regeneration. In addition, experiments using chlorine were conducted using concentrations ranging from 0.2 to 5.0 mg l −1. Chlorine experiments using exposure times of 105 min and three 20 min exposures in a 24 h period did not kill colonies but were effective in curtailing growth. Thermal treatments are preferred because they are effective and result in less environmental impact in receiving waters than chemicals.

Effect of Approach Velocity on Impingement of Juvenile Northern Pike at Water Intake Screens

AbstractCurrent guidelines with respect to the use of irrigation intakes limit Canadian operators to approach velocities (at the screen) of 3.8 cm/s; however, this value is based on relatively little data. To address this issue, I examined the ability of juvenile (2.3–7.4‐cm fork length) northern pike Esox lucius to avoid impingement on irrigation intake screens under ambient environmental conditions in a swim tunnel (where water velocity was constant and uniform) and in a simulated intake where water velocity declined with distance from the test screen (as in real structures). The effects of impingement duration (in swim tunnel tests) and approach velocity (in both tests) on feeding and physical condition (abrasions, bruising, and scale loss) were also examined. Juvenile northern pike in the swim tunnel became impinged at speeds ranging from 10 to 28 cm/s. Injuries and mortalities from impingement up to 10 min in duration were nonexistent, although some short‐term feeding disruptions were observed. Northern pike tested in the intake simulation apparatus never became impinged when the approach velocity was 15 cm/s; however, some impingement (but no feeding disruptions, injuries, or mortalities) was observed at an approach velocity of 25 cm/s. At higher velocities, impingement, feeding disruptions, injuries, and mortalities occurred. Environmental regulations pertaining to approach velocity at irrigation intake screens can be set as high as 15 cm/s without adversely affecting juvenile northern pike.