Effect of irradiance on the emission of short-lived halocarbons from three common tropical marine microalgae

Marine algae have been reported as important sources of biogenic volatile halocarbons that are emitted into the atmosphere. These compounds are linked to destruction of the ozone layer, thus contributing to climate change. There may be mutual interactions between the halocarbon emission and the environment. In this study, the effect of irradiance on the emission of halocarbons from selected microalgae was investigated. Using controlled laboratory experiments, three tropical marine microalgae cultures, Synechococcus sp. UMACC 371 (cyanophyte), Parachlorella sp. UMACC 245 (chlorophyte) and Amphora sp. UMACC 370 (diatom) were exposed to irradiance of 0, 40 and 120 µmol photons m−2s−1. Stress in the microalgal cultures was indicated by the photosynthetic performance (Fv/Fm, maximum quantum yield). An increase in halocarbon emissions was observed at 120 µmol photons m−2s−1, together with a decrease in Fv/Fm. This was most evident in the release of CH3I by Amphora sp. Synechococcus sp. was observed to be the most affected by irradiance as shown by the increase in emissions of most halocarbons except for CHBr3 and CHBr2Cl. High positive correlation between Fv/Fm and halocarbon emission rates was observed in Synechococcus sp. for CH2Br2. No clear trends in correlation could be observed for the other halocarbons in the other two microalgal species. This suggests that other mechanisms like mitochondria respiration may contribute to halocarbon production, in addition to photosynthetic performance.

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Capture of conspecific planktonic larvae by the suspension-feeding gastropod Crepipatella peruviana: association between adult and larval size

Journal of Molluscan Studies ◽

10.1093/mollus/eyab002 ◽

2021 ◽

Vol 87 (1) ◽

Author(s):

G A Rivera-Figueroa ◽

J A Büchner-Miranda ◽

L P Salas-Yanquin ◽

J A Montory ◽

V M Cubillos ◽

...

Keyword(s):

Laboratory Experiments ◽

Larval Mortality ◽

Feeding Preference ◽

The Other ◽

Suspension Feeding ◽

Adult Size ◽

Free Living ◽

Larval Size ◽

Suspension Feeders ◽

Planktonic Larvae

ABSTRACT Free-living, planktonic larvae can be vulnerable to capture and ingestion by adult suspension-feeders. This is particularly the case for larvae that settle gregariously in benthic environments where suspension-feeders occur at high densities. Larvae of gregarious suspension-feeding species are at particularly high risk, as adults of their own species often serve as cues for metamorphosis. We conducted laboratory experiments to assess the extent to which adults of the suspension-feeding caenogastropod Crepipatella peruviana would capture and ingest their own larvae. Experiments were conducted with adults of different sizes, with larvae of different ages and sizes, and in the presence or absence of phytoplankton. Adults captured larvae in all experiments. The presence of microalgae in the water did not influence the extent of larval capture. On average, 39% of larvae were captured during the 3-h feeding periods, regardless of adult size. However, up to 34% of the larvae that were captured on the gill were later discarded as pseudofaeces; the other 64% were ingested. The extent of capture by adults was not related to adult size, or to larval size and, thus, to larval age. Our results suggest that the filtration of congeneric larvae by adult C. peruviana is a result of accidental capture rather than a deliberate feeding preference. Such ingestion could, however, still be an important source of larval mortality, especially when the advanced larvae of this species are searching for a suitable substrate for metamorphosis.

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Characteristics of Particulate Matter Emissions from Swine and Poultry Production Houses in the United States

Transactions of the ASABE ◽

10.13031/trans.14622 ◽

2021 ◽

Vol 64 (5) ◽

pp. 1569-1579

Author(s):

Fei Hu ◽

Bin Cheng ◽

Lingjuan Wang-Li

Keyword(s):

Particulate Matter ◽

Broiler Chicken ◽

The United States ◽

The Other ◽

Emission Characteristics ◽

List Type ◽

Poultry Production ◽

Emission Rates ◽

Emission Data ◽

Poultry Houses

HighlightsParticulate matter (PM) data were analyzed to identify PM emission characteristics among different animal types.The PM concentrations were higher in broiler chicken and swine farrowing houses and were higher in winter.The PM emissions were also higher in broiler chicken houses and swine farrowing rooms.The PM in the layer chicken house in Indiana had narrower distributions with a greater percentage of smaller particles.Abstract. Understanding the characteristics of particulate matter (PM) emissions from animal feeding operations (AFOs) is essential to address the associated health and environmental impacts and to develop control strategies to mitigate such impacts. This article reports a study of PM concentrations and emission characteristics from 26 poultry and swine production houses to investigate the similarities and differences in PM emission characteristics, e.g., concentrations, emission rates, and particle size distribution (PSD), among different animal and housing types. Concentration and emission data for PM2.5, PM10, and total suspended particulates (TSP) collected by the National Air Emission Monitoring Study (NAEMS) were used to compare the differences among different production practices and animal types. The PSDs of the PM were examined based on the PM2.5/PM10 and PM10/TSP emission rate ratios. It was discovered that the concentrations of PM varied among animal types. For poultry, the concentrations of PM were higher in broiler houses than in other poultry houses. For swine, the average concentrations of PM were higher in farrowing rooms than in swine barns. Moreover, the PM concentrations in poultry and swine houses exhibited significant seasonal trends, with higher concentrations in winter and lower concentrations in summer, which were in a reverse relationship with ventilation rates. The PM emissions also varied among animal types. For poultry, the PM emissions were significantly higher for poultry production houses in California. For swine, the PM emissions were significantly higher for farrowing rooms than other swine houses. The PSD of PM varied among animal types, with mass median diameters (MMD) in the ranges of 6.51 to 13.62 µm for poultry houses and 7.94 to 17.19 µm for swine houses. The geometric standard deviations (GSD) were in the ranges of 1.66 to 2.71 and 1.65 to 2.9 for poultry and swine PM, respectively. The PM in the layer house in Indiana had a narrower distribution (smaller GSD) with a greater percentage of smaller particles than the other poultry houses, while the PM in the broiler house in California had a broader distribution (larger GSD) than the other poultry houses. For swine, the PM in the sow barn in North Carolina had a narrower distribution (smaller GSD) than the other swine houses, while the PM in the farrowing houses in Oklahoma had a broader distribution (larger GSD) than the other swine houses. The knowledge gained from this research may provide insights for addressing the PM emissions from various animal production systems. Keywords: Concentration and emission, Particulate matter, PM2.5, PM10, Poultry, swine, PSD, TSP.

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A Hooked-Collar for Bridge Piers Protection: Flow Fields and Scour

Water ◽

10.3390/w10091251 ◽

2018 ◽

Vol 10 (9) ◽

pp. 1251 ◽

Cited By ~ 10

Author(s):

Su-Chin Chen ◽

Samkele Tfwala ◽

Tsung-Yuan Wu ◽

Hsun-Chuan Chan ◽

Hsien-Ter Chou

Keyword(s):

Laboratory Experiments ◽

Horseshoe Vortex ◽

Flow Fields ◽

Bridge Pier ◽

The Other ◽

Bridge Piers ◽

Vortex Strength ◽

Numerical Tests ◽

Scour Hole ◽

New Type

A new type of collar, the hooked-collar, was studied through experiments and numerical methods. Tests were conducted using a hooked collar of a width of 1.25b and a height of 0.25b, where b is the bridge-pier width. The hooked-collar efficiency was evaluated by testing different hooked-collar placements within the bridge-pier, which were compared to the bridge-pier without any collar. A double hooked-collar configuration, one placed at the bed level and the other buried 0.25b, was the most efficient at reducing the scour hole. In other cases, a hooked-collar positioned 0.25b above the bed slightly reduced the scour hole and had similar scour patterns when compared to the pier without the hooked-collar. The flow fields along the vertical symmetrical plane in the experiments are also presented. Laboratory experiments and numerical tests show that maximal downflow is highly reduced along with a corresponding decrease in horseshoe vortex strength for the experiments with the hooked-collar, compared to cases without the hooked-collar. The flow fields reveal that the maximum turbulent kinetic energy decreases with the installation of the hooked-collar.

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Analysis of Cold-Developed vs. Cold-Acclimated Leaves Reveals Various Strategies of Cold Acclimation of Field Pea Cultivars

Remote Sensing ◽

10.3390/rs11242964 ◽

2019 ◽

Vol 11 (24) ◽

pp. 2964 ◽

Cited By ~ 1

Author(s):

Alexandra Husičková ◽

Jan F. Humplík ◽

Miroslav Hýbl ◽

Lukáš Spíchal ◽

Dušan Lazár

Keyword(s):

Cold Acclimation ◽

Shoot Growth ◽

Photosynthetic Performance ◽

The Other ◽

Remote Sensing Technology ◽

Sensing Technology ◽

Quenching Analysis ◽

Shoot Growth Rate ◽

Whole Plants

Peas (Pisum sativum L.) belong among the world’s oldest domesticated crops, serving as a source of proteins, complex carbohydrates, vitamins and minerals. Autumn sowing allows a higher biomass production as well as the avoidance of the drought and heat stresses of late spring. However, the character of European continental winters limits plant growth and development through cold stress. This work sought parameters that reflect the cold tolerance of pea plants and consequently to suggest an afila-type pea cultivar with resilience to European continental winters. For this purpose, we employed indoor remote sensing technology and compared the 22-day-long acclimation to 5 °C of four pea cultivars: Arkta, with normal leaves and the known highest cold resistance to European continental winters, and Enduro, Terno and CDC Le Roy, all of the afila type. Besides evaluation of shoot growth rate and quenching analysis of chlorophyll fluorescence (ChlF) by imaging methods, we measured the chlorophyll content and ChlF induction with a nonimaging fluorometer. Here we show that the acclimation to cold of the Arkta exhibits a different pattern than the other cultivars. Arkta showed the fastest retardation of photosynthesis and shoot growth, which might be part of its winter survival strategy. Terno, on the other hand, showed sustained photosynthetic performance and growth, which might be an advantageous strategy for spring. Surprisingly, Enduro showed sustained photosynthesis in the stipules, which transferred and acclimated to 5 °C (cold-acclimated). However, of all the cultivars, Enduro had the strongest inhibition of photosynthesis in new stipules that developed after the transition to cold (cold-developed). We conclude that the parameters of ChlF spatial imaging calculated as averages from whole plants are suboptimal for the characterization of various cold acclimation strategies. The most marked changes were obtained when the new cold-developed leaves were analyzed separately from the rest of the plant.

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Antiviral activity of the green marine alga Ulva fasciata on the replication of human metapneumovirus

Revista do Instituto de Medicina Tropical de São Paulo ◽

10.1590/s0036-46652010000100001 ◽

2010 ◽

Vol 52 (1) ◽

pp. 03-10 ◽

Cited By ~ 11

Author(s):

Gabriella da Silva Mendes ◽

Angélica Ribeiro Soares ◽

Fernanda Otaviano Martins ◽

Maria Carolina Maciel de Albuquerque ◽

Sonia Soares Costa ◽

...

Keyword(s):

Antiviral Activity ◽

Viral Entry ◽

Marine Algae ◽

Marine Alga ◽

Biological Properties ◽

Human Metapneumovirus ◽

The Other ◽

Virucidal Activity ◽

Ulva Fasciata ◽

Viral Particles

We evaluated the antiviral activity of the marine alga, Ulva fasciata, collected from Rasa beach and Forno beach, Búzios, Rio de Janeiro, Brazil on the replication of human metapneumovirus (HMPV). The algae extracts were prepared using three different methodologies to compare the activity of different groups of chemical composites obtained through these different methodologies. Four out of the six extracts inhibited nearly 100% of viral replication. The results demonstrated that the majority of the extracts (five out of six) possess virucidal activity and therefore have the ability to interact with the extracellular viral particles and prevent the infection. On the other hand, only two extracts (from Forno beach, obtained by maceration and maceration of the decoction) were able to interact with cell receptors, hindering the viral entry. Finally, only the extract of algae collected at Forno beach, obtained by maceration presented intracellular activity. To our knowledge, this is a pioneer study on antiviral activity of marine algae against HMPV. It is also the first on antiviral activity against HMPV ever done in Brazil. The study also shows the effect of different environment factors and different chemical procedures used to obtain the extract on its biological properties.

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Effects of juvenile hormone mimics on the codling moth Cydia Pomonella (L.) (Lep., Olethreutidae)

Bulletin of Entomological Research ◽

10.1017/s0007485300050847 ◽

1973 ◽

Vol 63 (1) ◽

pp. 7-16 ◽

Cited By ~ 22

Author(s):

I. Gelbič ◽

F. Sehnal

Keyword(s):

Juvenile Hormone ◽

Laboratory Experiments ◽

Cydia Pomonella ◽

Codling Moth ◽

The Other ◽

Wide Range ◽

Juvenile Hormone Analogues ◽

Juvenile Hormone Mimics

AbstractLaboratory experiments with juvenile hormone analogues on Cydia pomonella (L.) showed that Cecropia C17 juvenile hormone (methyl 10,ll-epoxy-3,7,ll-trimethyl-2,6-dodecadienoate) was the most active of the 28 compounds tested. When applied to four-hour-old eggs at 0.1 μg/egg, the hormone caused 100% failure in embryogenesis, while the other compounds were at least five times less effective. Depending on the time since ecdysis and the dose, juvenile hormone mimics applied to last-instar larvae resulted in a wide range of intermediate forms. Against three-day-old last-instar larvae, the Cecropia C17 hormone gave 100% inhibition of development at a dose of 1 μg/larva, while three other compounds (methyl 10,11-epoxy-3,7,11-trimethyl-2,6-dodecadienoate, ethyl 11-chloro-3,7,11-trimethyl-2-dodecenoate and ethyl 3,7,11-tri-methyl-2,4-dodecadienoate) gave the same effect at 2–5 μg/larva. Against newly emerged adults, the last two compounds at 10–50 μg/insect reduced fecundity and fertility to 0–81% and 0–50%, respectively, of their normal levels.

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GERMINATION OF ALFALFA VARIETIES IN SOLUTIONS OF VARYING OSMOTIC PRESSURE AND RELATIONSHIP TO WINTER HARDINESS

Canadian Journal of Plant Science ◽

10.4141/cjps59-051 ◽

1959 ◽

Vol 39 (3) ◽

pp. 384-394 ◽

Cited By ~ 13

Author(s):

D. H. Heinrichs

Keyword(s):

Sodium Chloride ◽

Osmotic Pressure ◽

Laboratory Experiments ◽

Reliable Method ◽

Winter Hardiness ◽

The Other ◽

General Tendency ◽

Salt Solutions ◽

Sodium Chloride Solutions ◽

Alfalfa Varieties

Two laboratory experiments were conducted to evaluate the reliability of amount of germination in solutions of varying osmotic pressure, as a means of separating alfalfa varieties into winter-hardiness classes. In one test 23 varieties or strains were studied, and in the other 36. It was found that significant differences exist between certain alfalfa varieties in their ability to germinate in sucrose or sodium chloride solutions of 3, 6, and 9 atmospheres. There is a general tendency for non-hardy varieties to germinate more rapidly and more completely than hardy ones but there are many exceptions to this trend. Germination in solutions of 6 atmospheres osmotic pressure at 5 days gave the best separation of varieties on the basis of their ability to germinate. Germination was generally better in solutions of sucrose at 6 atmospheres osmotic pressure than in solutions of sodium chloride of the same osmotic pressure but several varieties germinated equally well in either solution. The results indicate that germinating alfalfa in sugar or salt solutions is not a reliable method for differentiating alfalfa varieties into winter hardiness classes.

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Betaine Yields from Marine Algal Species Utilized in the Preparation of Seaweed Extracts Used in Agriculture

Natural Product Communications ◽

10.1177/1934578x1000500418 ◽

2010 ◽

Vol 5 (4) ◽

pp. 1934578X1000500 ◽

Cited By ~ 6

Author(s):

Gerald Blunden ◽

Peter F. Morse ◽

Imre Mathe ◽

Judit Hohmann ◽

Alan T. Critchley ◽

...

Keyword(s):

Marine Algae ◽

Algal Species ◽

First Record ◽

Commercial Production ◽

The Other ◽

Minor Constituent ◽

Laminaria Digitata ◽

Seaweed Extracts ◽

Marine Algal ◽

A Minor

Ascophyllum nodosum, and to a lesser extent, Laminaria digitata, L. hyperborea and Fucus serratus, are marine algal species utilized in the commercial production of seaweed extracts used in agriculture. Betaines have been shown to be important constituents of these extracts, but there appears to have been no study made on whether there are variations in the betaine contents of these species based on either the place or date of collection. Samples of each of the four species were collected from widely separated areas at different times of the year. Also, in the case of A. nodosum, approximately monthly collections were made from one location. The betaines detected in the various collections of the same species showed little variation, although in the case of A. nodosum, glycinebetaine was found as a minor constituent in some samples, but was not detected in others. Trigonelline was found in all the tested samples of the two Laminaria species; this is, to our knowledge, the first record of this betaine in marine algae. With the exception of trigonelline in the Laminaria species, the betaine yields from the various samples of L. digitata, L. hyperborea and F. serratus showed little variation, regardless of either the place or date of collection. The trigonelline contents of the Laminaria species collected at one location (Finavarra, Ireland), in particular of L. hyperborea, was substantially greater than those from the other places of collection. In the case of A. nodosum, the betaine yields from samples collected at one site (Dale, Pembrokeshire, UK) were significantly higher than those from the other places of collection, which were very similar to each other. There was no clear indication of seasonal variation in betaine yields from A. nodosum.

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Carbon monoxide emissions by phytoplankton: evidence from laboratory experiments

Environmental Chemistry ◽

10.1071/en09020 ◽

2009 ◽

Vol 6 (5) ◽

pp. 369 ◽

Cited By ~ 12

Author(s):

Valérie Gros ◽

Ilka Peeken ◽

Katrin Bluhm ◽

Eckart Zöllner ◽

Roland Sarda-Esteve ◽

...

Keyword(s):

Carbon Monoxide ◽

Organic Matter ◽

Dissolved Organic Matter ◽

Atmospheric Chemistry ◽

Laboratory Experiments ◽

Euphotic Zone ◽

Global Scale ◽

Emission Rates ◽

Direct Production ◽

Diurnal Cycles

Environmental context. Carbon monoxide (CO) is a key component for atmospheric chemistry and its production in the ocean, although minor at the global scale, could play a significant role in the remote marine atmosphere. Up to now, CO production in the ocean was considered to mainly originate from the photo-production of dissolved organic matter (mainly under UV radiation). In this paper, we show evidence for direct production of CO by phytoplankton and we suggest it as a significant mechanism for CO production in the ocean. Abstract. In order to investigate carbon monoxide (CO) emissions by phytoplankton organisms, a series of laboratory experiments was conducted in Kiel (Germany). Nine monocultures, including diatoms, coccolithophorids, chlorophytes and cyanobacteria have been characterised. This was done by following the CO variations from monoculture aliquots exposed to photosynthetically active radiation during one or two complete diurnal cycles. All the studied cultures have shown significant CO production when illuminated. Emission rates have been estimated to range from 1.4 × 10–5 to 8.7 × 10–4 μg of CO μg chlorophyll–1 h–1 depending on the species. When considering the magnitude of the emission rates from the largest CO emitters (cyanobacteria and diatoms), this biotic source could represent up to 20% of the CO produced in oceanic waters. As global models currently mainly consider CO production from the photo-degradation of dissolved organic matter, this study suggests that biotic CO production should also be taken into account. Whether this biological production might also contribute to some degree to the previous observed non-zero CO production below the euphotic zone (dark CO production) cannot be deduced here and needs to be further investigated.

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Thinking orientation and preference for research methodology

Journal of Consumer Marketing ◽

10.1108/jcm-01-2016-1694 ◽

2016 ◽

Vol 33 (6) ◽

pp. 437-446 ◽

Cited By ~ 1

Author(s):

Feisal Murshed ◽

Yinlong Zhang

Keyword(s):

Research Methodology ◽

Design Methodology ◽

Laboratory Experiments ◽

Qualitative Methodology ◽

Marketing Research ◽

Cross Cultural ◽

The Other ◽

Content Type ◽

Holistic Thinking ◽

Practical Implications

Purpose This research aims to investigate how preference for marketing research methodology (quantitative vs qualitative) is contingent on the thinking orientation (analytic vs holistic) of the researchers. Design/methodology/approach Thinking orientation was measured and then manipulated in laboratory experiments. Cross-cultural evidence was sought by comparing Western and East Asian participants. Findings Results demonstrate that researchers with an analytic (holistic) thinking orientation tend to perceive quantitative (qualitative) methodology more favorably. Further, the need to offer reasons in support of the choice strengthened the effect of thinking orientation. Practical implications Understanding researchers’ preferences for one research methodology over the other has broad relevance for external constituents, as it involves a great deal of managerial commitment in terms of time and money and can affect the results of the research. Originality/value This is the first study to investigate factors that underlie researchers’ choice regarding research methodology, and it also extends the literature on analytic versus holistic thinking orientation in the marketing field.

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