Harmful Algae

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Potentially Harmful Algae along the Kenyan Coast: A Norm or Threat.

Potentially Harmful Algae along the Kenyan Coast: A Norm or Threat.

Harmful algae species are greatly influenced by local and regional environmental changes by inducing harmful algae proliferation, thus increasing toxins concentrations (van Dolah, 2000). For instance, the magnitude and the timing of inflows influence the physicochemical environment and bring about variations in salinity, nutrient availability, stratification and hydraulic flushing. In turn, these affect plankton community composition and productivity (Buyukates and Roelke, 2005; Miller et al., 2008). In bays and estuaries, inflows from rivers and tidal waters can stimulate system-level productivity and alter community composition by influencing essential nutrients, hypersaline conditions and connectivity between habitats (Cloern, 2001; Fejes et al., 2005; Heinsch et al., 2004; Miller et al., 2009). This has affected the incidence of HABs observed over a wide range of taxa that include cyanobacteria, dinoflagellates, diatoms and prymnesiophytes (Jacoby et al., 2000; Roelke et al., 2010; Spatharis et al., 2007).
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Harmful Algae 8 (2009) Contents lists available at ScienceDirect. Harmful Algae. journal homepage:

Harmful Algae 8 (2009) Contents lists available at ScienceDirect. Harmful Algae. journal homepage:

To determine the extent of monetary losses that some firms may have incurred due to blooms of Karenia brevis (red tides) in Southwest Florida, 7 years of daily proprietary data were obtai[r]

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An Investigation into How Mixotrophy and Deleterious Chemical Production Give Harmful Algae a Competitive Advantage in Systems Influenced by Anthropogenic Disturbance

An Investigation into How Mixotrophy and Deleterious Chemical Production Give Harmful Algae a Competitive Advantage in Systems Influenced by Anthropogenic Disturbance

(Shade et al., 2012), a specific system will likely have a characteristic environmental fluctuation regime to which organisms are adapted. Here I present a case study in which it is investigated how the effects of co-occurring disturbances might interact to influence the abundance of a harmful algal bloom-forming species, Prymnesium parvum (Carter, 1937). Specifically, the experimentally manipulated disturbances included increased salinity and community composition change via the removal of large zooplankton. The effects of the co-occurring disturbances were tested at two propagule levels, ambient and elevated P. parvum densities, treating elevated P. parvum density as a third disturbance. The role that historical exposure to salinity related fluctuations played in influencing the effect of these co-occurring disturbances was also examined.
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NIH Public Access Author Manuscript Harmful Algae. Author manuscript; available in PMC 2011 January 1.

NIH Public Access Author Manuscript Harmful Algae. Author manuscript; available in PMC 2011 January 1.

Although brevetoxin-related illnesses (both NSP and respiratory irrigation) and other harmful algal bloom diseases have been described in the medical literature, these diseases are significantly under-reported to public health authorities (Fleming et al. 2002; Backer et al. 2003; Backer et al. 2005, Watkins et al., 2008). They are under-reported because both victims and healthcare providers misdiagnose these illnesses as “food poisoning” or “asthma” without further investigation into the actual cause, and victims often do not seek formal medical care. In addition, most healthcare providers, even in endemic areas such as Sarasota (FL), are unaware of the range of exposure possibilities for brevetoxin, including the fact that whole fish (as well as shellfish), contaminated aerosols, and seawater may serve as causes of brevetoxin- associated illness in humans. This study is the first indication that the incidence of
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Anthropogenic nutrients and harmful algae in coastal waters

Anthropogenic nutrients and harmful algae in coastal waters

The above discussion has concentrated on N and P. However, one important phytoplankton class, the diatoms, also require sili- con (Si) to build their cell wall. The potential for diatom Si limitation is exacerbated by low Si concentration in sewage ef fluent and agricultural runoff, with a low Si:N ratio potentially promoting dino flagellates ( Davidson and Gurney, 1999; Of ficer and Ryther, 1980 ), a group that contains relatively more harmful species. Prominent examples of anthropogenically elevated N:Si ratios include the southern North Sea, German Bight, and Baltic Sea ( Gieskes et al., 2007; Hickel, 1998; Humborg et al., 2008 ). As Si is used structurally, it cannot be redistributed easily within phyto- plankton cells, and therefore the consequences of its low avail- ability are different than N and P, with theoretical models suggesting that extracellular concentrations are important in gov- erning growth rate ( Flynn and Martin-jezequel, 2000 ). While most field studies confirm that Si limitation promotes flagellates over diatoms, de finitive evidence that HAB species, other than the nuisance Phaeocystis, prosper under these conditions is lacking ( Tett et al., 2003 ). Hence, the assertion that changing N:Si will promote HABs is based on the likelihood that a dino flagellate- dominated phytoplankton assemblage contains more HAB spe- cies, rather than any speci fic evidence for the creation of ecological niches favouring HAB species.
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Are toxins from harmful algae a factor involved in the decline of harbour seal populations in Scotland?

Are toxins from harmful algae a factor involved in the decline of harbour seal populations in Scotland?

The most harmful toxins arise from the PSP toxin group and ever since an outbreak in the North east of England in 1968 where 78 people were admitted to the hospital displaying PSP symptoms, toxins from this group have been monitored (Ayres and Cullum, 1978). Toxins from the ASP and DSP group have also been monitored in more recent years (Gallacher et al., 2000; Turrell et al., 2007). However, toxins from the PSP group remain the most important toxin to monitor due to their potential to harm wildlife and humans and in Scottish waters almost every year shellfish farms are closed due to high concentrations of PSP toxins (exceeding the European Community regulatory limit of 80 µ g STX equivalents (eq) 100 g − 1 of shellfish flesh) (Stobo et al., 2008). Since the monitoring of DSP started in 1992 there has been an annual recording of this toxin in Scottish waters (Stobo et al., 2008). It has been known that toxins from the ASP group could have existed prior to the monitoring, that first commenced in 1998. Shellfish with DA concentrations above the regulatory limit (20 µ g ASP toxins g − 1 shellfish flesh) occurred since 1999 with a peak around year 2000 (Stobo et al., 2008). Interestingly, this is around the time when the Scottish harbour seal population in some regions also started declining (Lonergan et al., 2007)
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Oregon Harmful Algae Bloom Surveillance (HABS) Program. Public Health Advisory Guidelines Harmful Algae Blooms in Freshwater Bodies

Oregon Harmful Algae Bloom Surveillance (HABS) Program. Public Health Advisory Guidelines Harmful Algae Blooms in Freshwater Bodies

Advisory guidelines for algae blooms not dominated by Microcystis or Planktothrix: At 100,000 cells/mL, the World Health Organization lists a moderate probability of adverse health effects, based in part on the ability of cyanotoxins to reach levels of concern. As the cell density increases, the potential for frequently occurring cyanobacteria to form scum may increase toxin production by 1000x in a few hours (Chorus and Bartram, 1999).

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Making Algae Biodiesel at Home

Making Algae Biodiesel at Home

Covering all aspects of biodiesel, biofuels, and alternative energy. He is also the Managing Director of International Biofuel Solutions, LTD. Thailand and President of Information Specialists, Corp., USA He lives in Des Moines, Iowa USA with his wife, Tram and Son, Lennon. These guides were written with the intent of providing “Quick and Dirty” realistic, no BS, info on all aspects of the algae to biodiesel process. If you liked this EBook, we’d like to hear about it. If you didn’t like it, WE’D REALLY LIKE TO HEAR ABOUT IT. Your comments will help make future editions of this eBook even better. Don’t hesitate to sound off.
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Algae biodiesel - a feasibility report

Algae biodiesel - a feasibility report

By 1988, researchers have successfully identified the enzyme Acetyl CoA Carboxylase (ACCase), which has shown positive correlation with lipid buildup during Si- depletion. These findings quickly prompted scientists to successfully clone the ACCase gene and to develop tools for expressing foreign genes in diatoms. In the 1990s, the ASP program accelerated rapidly and focused heavily on the genetic engineering front. At around the same time, another line of research that focused on the carbon meta- bolic pathway also yield a substantial discovery (Figure 2). Instead of focusing on the lipid synthesis, scientists iden- tified key enzymes involved in the synthesis of carbohy- drate and ways to disable them, thus diverting carbon to flow down the lipid synthesis pathway. However, the ben- efits of these findings have yet outweighed the loss from inhibitive growth rate due to depleted cells. Molecular research still needs to balance the efficiency of lipid pro- duction with algae growth, because those are two essen- tial criteria for a viable algae farm environment.
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Volvox and volvocine green algae

Volvox and volvocine green algae

Terminally differentiated somatic cells are a hallmark of complex multicellular organisms and are likely to have arisen independently at least three times in volvocine algae [5]. In V. carteri, maintenance of somatic differ- entiation is governed by a somatic cell-specific SAND domain transcription factor, RegA, which is part of a vol- vocine algal specific VARL family that underwent a com- plex history of duplications in multicellular volvocine genera [25–27]. Germ–soma differentiation in V. cart- eri occurs shortly after embryogenesis is complete, and is dictated by postembryonic cell size; but the coupling between cell size and cell fate remains a mystery [28]. Recent cell-type transcriptome studies in Volvox have also shed light on how germ and somatic cells differ, and the potential origins of their specialized differentiation programs [29–31]. Much remains to be discovered in this system including identifying direct targets of RegA, identification of germ cell-specific differentiation factors, and determining how asymmetric cell divisions governed by the chromatin-associated chaperone proteins glsA, Hsp70A and other factors are specified and executed [32].
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Supercritical Water Gasification Of Algae

Supercritical Water Gasification Of Algae

Table 6.4 Nutrients and important metals in ppm from the process waters following HTL Chlorella at varying hold time and SCWG of the HTL process water at 30 min at different organic concentration...... 200 Table 6.5 Gas yields (mol kg -1 algae), hydrogen yield per gram of

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Algae fuels as an alternative to petroleum

Algae fuels as an alternative to petroleum

The high capital cost of establishing algae farms, both for growth systems and for downstream processing equipment, is a primary economic factor in the cost of biocrude/oil production. The reduction of initial CAPEX and the improvement of biomass productivity are both primary effectors in sensitivity analysis of the economics [33]. The growth of algae in land-based aquatic systems necessitates high rates of water transfer and the high water content of algae biomass can also present challenges in achieving economical dewatering with low energy inputs. Water sustainability (due to evaporation losses) has been highlighted as an issue for mass cultivation of algae [34], although water sustainability is similarly a concern for other primary production systems [35-37] and with the use of saline and waste water resources algae biomass can be produced with around 10 times less freshwater for microalgae than many conventional crops [38] and even less freshwater required for macroalgae cultivation. Nevertheless, for the large scale of production required to contribute ~10% or more of global fuel use, good water management practices must be engaged and access to sufficient sources of suitable water must be ensured [39,40]. Importantly, the vast majority of the world’s 15 million tonne per annum production of macroalgae, valued at US$8 billion (at costs of ~$350-3,500 T -1 [41]), is produced in-sea with natural flow delivering
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Scenario studies for algae production

Scenario studies for algae production

The raceway pond energy balance was applied to determine the dynamic temperature of the pond water. A recently developed approach uses dimensionless numbers for heat transfer and evaporation phenomena [127], while the classical approach is based on well-established empirical relationships. In this work the last approach is used. The energy flows due to solar irradiation, light absorption by algae, convection, evaporation, condensation, conduction and longwave radiation are considered (see Figure 2). Changes in water volume due to evaporation or precipitation are assumed to be balanced by an overflow/inflow system that does not affect the energy balance. The system is considered to be well-mixed with a constant volume and a flat and opaque water surface. The solar irradiance input is derived from weather data and reflected light is removed from the energy flow. Longwave radiation from both pond and air are calculated using the Stefan-Boltzmann expression [103]. Estimation of evaporative flows from saline water bodies is not straightforward [130] and detailed information on the most appropriate method for raceway ponds is lacking [127]. Evaporation rates are calculated from the heat exchange coefficient introduced by McMillan [131]. Convection is related to evaporation and follows from the Bowen relation [132]. Conduction between the pond and soil is based on Fourier’s law. The soil is considered as an infinite source for heat transfer as a first approximation. Further explanation and an overview of the used equations for the energy balance can be found in Appendix A.
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Waste Water Treatment by Algae

Waste Water Treatment by Algae

Abstract: As many research works are going on in the field of wastewater treatment, a newly developed wastewater treatment by algae is gaining much importance. The algae selected for the study was Oedogonium and Chara sp. Various parameters like Biological oxygen demand (BOD), Chemical oxygen demand (COD), Ammonia Nitrogen and Phosphate were observed after the treatment. Percentage reduction rate of 59.61(BOD), 53.97 (COD) were observed. This is an environmentally safe alternative for treating wastewater.
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Algae as Functional Foods for the Elderly

Algae as Functional Foods for the Elderly

Marine algae represent the most important non-animal source of sulphated polysac- charides. These compounds are anionic polymers which structure varies according to the algal species [18]. Their biological activities depend on chemical structure, molecu- lar weight and chain conformation [19]. The most abundant SP found in marine algae are fucoidan and laminarans of brown algae, carrageenan of red algae and ulvan of green algae [20] [21]. Fucoidans have been reported by their antioxidant, anti-inflammatory, anti-allergic, anti-tumour, anti-obesity, anti-coagulant, anti-viral, anti-hepatopathy, anti-uropathy and anti-renalpathy effects. Plus, they are widely available commercially from various cheap sources when compared to other SP. Hence, they have been more and more investigated to develop functional foods [22], for disease prevention and health promotion [23]. Fucoindans from seaweeds are heterogenic compounds, being a mixture of structurally related polysaccharides with certain variations of the content of carbohydrate units and non-carbohydrate substituents [24]. They are essentially com- posed of fucose and sulphate, and also contain other monosaccharides like mannose, galactose, glucose, xylose, etc., and uronic acids [23].
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The mechanics of wave swept algae

The mechanics of wave swept algae

As noted previously, in the absence of flow, most nearshore algae are not noticeably streamlined. However, as a result of the structural flexibility of algal fronds, this impression can be misleading. In unidirectional flow, fronds bend in response to the applied force, and the plant reorients and rearranges passively in a manner that results in an overall streamlining (Koehl, 1984, 1986; Koehl and Alberte, 1988). As a consequence, β for wave-swept algae in flow is universally less than 2 (typically approximately 1.5), and values as low as 0.8–0.9 have been reported (Carrington, 1990; Bell, 1999; Gaylord et al., 1994; Gaylord, 2000). There seems to be little correlation between the still-water shape of an alga and its in- flow value of either β or C. In other words, the flexibility of algae (due both to their basic body plan and to the compliance of their materials) allows fluid-dynamic forces to be decoupled from shape – in rapid, steady flows many wave-swept algae seem to be approximately equally streamlined.
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Algae Biodiesel A Feasibility Report

Algae Biodiesel A Feasibility Report

On the other hand, the major cost involved in biodiesel sourced from open pond systems is the cost of CO 2 input, while the capital costs are very low. While yield can never be as high as in closed systems – 50% would appear to be a pipe dream for open ponds – they certainly can be improved. Finally, as before, hexane recovery could also reduce costs. Scenarios are presented in Table 14. Improved yields greatly help algae biofuels to nearly achieve the cusp of economic feasibility. However, it is somewhat difficult to envision improvements past 30% yields for open systems. Nevertheless, combined with reductions in CO 2 costs, open pond sourced biodiesel is at the cusp of feasibility. Essentially, for algae to be close to economically feasible as a biofuel simply requires little to no CO 2 cost and an open pond system with reasonable lipid yields. We will now go over possible policies that may tip the balance.
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Algae and Cyanobacteria in Soils of Moscow

Algae and Cyanobacteria in Soils of Moscow

The studies of algal-cyanobacterial communities are performed in several cities of Russia (Monchegorsk and Ekaterinburg [14], Ufa [3] [15], Krasnoyarsk [16], and Kirov [17]) and Ukraine (Lugansk [18] and Mariupol [19]). Algae and cyanobacteria in the urban recreation zones and on the lawns near motor roads are best unders- tood. Most works deal with flora problems; only few authors also studies the urban soils and discuss the effect of their physicochemical properties on the composition of soil algae and cyanobacteria [18] [20]. Little data are still available on the impact of heavy metals (HMs) and deicing salt agents accumulated in the urban soils on the algal-cyanobacterial communities.
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Distributed Development Considered Harmful?

Distributed Development Considered Harmful?

Second: “recheck” old results if new results call them into question. Many papers say distributed development can be harmful to software quality. Previous work by Bird et al. allayed that concern but a recent paper by Posnett et al. suggests that the Bird result was biased by the kinds of files it explored. Hence, this paper rechecks that result and finds significant differences in Microsoft products (Office 2010) between software built by distributed or collocated teams. At first glance, this recheck calls into question the widespread practice of distributed development. Our third rule is to “reflect” on results to avoid confusing practitioners with an arcane mathematical analysis. For example, on reflection, we found that the effect size of the differences seen in the collocated and distributed software was so small that it need not concern industrial practitioners.
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Nematodes harmful to strawberries

Nematodes harmful to strawberries

Meloidogyne hapla. Nematode species A. fragariae cause twisting and puckering of leaves, delayed development of the plants, reddened and stunted petioles, flowers talks with aborted or partly aborted flowers and lowering yields strawberries to 60 %. In addition to crop rotation and planting of healthy plants, a significant role in preventing the spread of this pest has a sinking seedlings in water heated to 43.3 ° C for 20 min. Species M. hapla is harmful in strawberry production outdoors and in greenhouses. The infection is recognized based on the appearance of root nodules and the formation of many fine roots. Plants of strawberries become dwarf, leaves become chlorotic and red, what it is followed by reduced yield. The most infected plants can be completely dry. As this species has about 550 host plants, the selection of plants in the rotation is demanding. Reducing populations of these nematodes is achieved by draining of the soil, weed control, planting enemy plants (Tagetes spp., Asparagus spp.) and the planting of resistant and tolerant plants. The best results are achieved by thermal sterilization of the soil, solarization and chemical sterilization before planting.
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