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The River Ganga is reeling from pressures of rapid urbanization and resulting anthropogenic forcings. In this study, phytoplankton community assemblages were deduced from the Dakshineswar site located in the lower stretch of River Ganga to quantify and understand the health status of this river. Surface water samples were collected from six pre-defined stations of Dakshineswar spanning across monsoon and post-monsoon seasons of 2019 and 2020. Stations were categorized into point source and surface water based on proximity to municipal discharges. Measurement of in situ environmental parameters showed significant differences in values for dissolved oxygen, total dissolved solids, electrical conductivity and suspended particulate matter between the two seasons during the study period. In particular, concentrations of dissolved nitrate and silicate were found to be higher in point source stations compared to surface water stations. The concentration of Chlorophyll-a (Chl-a) was found to be higher in post-monsoon compared to monsoon seasons. Phytoplankton communities consisted of 23 diatom taxa and 14 green algal taxa and they showed distinct seasonal and spatial variations in the study site. Phytoplankton communities were dominated by diatom taxa namely Aulacoseira , Bacillaria, Coscinodiscus , and green algal taxa such as Ulothrix, Chlorella, and Scenedesmus . There was a dramatic increase in cell abundance of Aulacoseira spp. in post-monsoon seasons indicating a bloom-like scenario. Moreover, the rapid increase in cell abundance of Aulacoseira spp. also coincided with an increase in Chl-a and a sharp fall in the concentration of dissolved silicate. Some of the encountered phytoplankton taxa such as Tetraedron , Cosmarium, Nitzschia and Scenedesmus showed strong co-occurrence patterns indicating possible association at ecological scales. Four distinct clusters were formed in nMDS ordination plot based on the influences of environmental variables on encountered phytoplankton taxa. Network analysis revealed evidence of co-occurrence patterns between several diatoms and green algal taxa.

The genus Phaeocystis is globally distributed, with blooms commonly occurring on continental shelves. This unusual phytoplankter has two major morphologies: solitary cells and cells embedded in a gelatinous matrix. Only colonies form blooms. Their large size (commonly 2 mm but up to 3 cm) and mucilaginous envelope allow the colonies to escape predation, but data are inconsistent as to whether colonies are grazed. Cultured Phaeocystis can also inhibit the growth of co-occurring phytoplankton or the feeding of potential grazers. Colonies and solitary cells use nitrate as a nitrogen source, although solitary cells can also grow on ammonium. Phaeocystis colonies might be a major contributor to carbon flux to depth, but in most cases, colonies are rapidly remineralized in the upper 300 m. The occurrence of large Phaeocystis blooms is often associated with environments with low and highly variable light and high nitrate levels, with Phaeocystis antarctica blooms being linked additionally to high iron availability. Emerging results indicate that different clones of Phaeocystis have substantial genetic plasticity, which may explain its appearance in a variety of environments. Given the evidence of Phaeocystis appearing in new systems, this trend will likely continue in the near future.

The gut microbiome plays important roles in host function and health. Core microbiomes have been described for different species, and imbalances in their composition, known as dysbiosis, are associated with pathology. Changes in the gut microbiome and dysbiosis are common in aging, possibly due to multi-tissue deterioration, which includes metabolic shifts, dysregulated immunity, and disrupted epithelial barriers. However, the characteristics of these changes, as reported in different studies, are varied and sometimes conflicting. Using clonal populations of Caenorhabditis elegans to highlight trends shared among individuals, we employed 16s rRNA gene sequencing, CFU counts and fluorescent imaging, identifying an Enterobacteriaceae bloom as a common denominator in aging animals. Experiments using Enterobacter hormaechei , a representative commensal, suggested that the Enterobacteriaceae bloom was facilitated by a decline in Sma/BMP immune signaling in aging animals and demonstrated its potential for exacerbating infection susceptibility. However, such detrimental effects were context-dependent, mitigated by competition with commensal communities, highlighting the latter as determinants of healthy versus unhealthy aging, depending on their ability to restrain opportunistic pathobionts., Competing Interests: Conflict of interest statement. The authors declare that they have no actual or apparent conflict of interest between authorship of this study and any other activities.

Since 1987, as many as 16 southeastern US states participate in a 4 wk annual spring Dendroctonus frontalis (Zimmerman) (Coleoptera: Curculionidae) trapping survey. The purpose of the survey is to assess the current D. frontalis outbreak potential, and anticipate prevention and suppression needs for the coming yr. This prediction system relies on capturing the peak D. frontalis spring dispersal, thus timing of trap deployment is crucial. Forest managers traditionally attempt to deploy traps at the onset of flowering dogwood (Cornus florida L.; Cornaceae) bloom, which is commonly assumed to coincide with peak D. frontalis spring dispersal. The objective of this study is to examine the validity of dogwood bloom as an indicator of peak D. frontalis spring dispersal. Yr-round trapping data in 2014 and 2015 from Mississippi and Florida were used to identify peak D. frontalis and Thanasimus dubius (Fabricius) (Coleoptera: Cleridae) dispersal periods. Peak D. frontalis dispersal then was compared with dogwood blooming dates from the USA National Phenology Network and personal records. Then, both dogwood bloom dates and peak D. frontalis dispersal were compared with timing of actual historic state D. frontalis trapping efforts. We also compared peak D. frontalis dispersal with T. dubius peak dispersal, because T. dubius trap captures are used in the prediction model. Last, we examined the utility of extending the spring survey to 6 wk by comparing the 4 wk peak D. frontalis trap captures with a corresponding 6 wk peak. On average, mean onset of dogwood bloom occurred 3 wk after the peak 4 wk period of D. frontalis flight activity. The average T. dubius peak dispersal occurred 1.5 wk after peak D. frontalis dispersal. The 6 wk extension provided only a 12% overall average increase in D. frontalis trap captures. Eastern redbud (Cercis canadensis L.; Fabaceae) also had been suggested as a replacement trap deployment cue; therefore, eastern redbud and flowering dogwood blooming dates in 2019 were monitored on a Mississippi State University property in Oktibbeha County, Mississippi, USA. On this site eastern redbud trees bloomed on average 2.3 wk before the average bloom date of flowering dogwood trees. [ABSTRACT FROM AUTHOR]

Based on the discussion on the shape, nature, iron-smelting products and technical characteristics of the "bowl-shaped" bloomeries of the iron-smelting remains of the Han dynasty at Liuchen Town in Pingnan County, Guangxi Zhuang Autonomous Region, this paper puts forward the issue of the origin of the "bowl-shaped" bloomeries in China, and referring to the "bowl-shaped" bloomeries found in West Asia, South Asia, Europe, and Africa and their smelting technical traditions. This paper pointed out that the "bowl-shaped" bloomeries in China had the same origin with that of the other regions of the world, which was the result of the far and wide diffusion of the "bowl-shaped" bloomeries of West Asia, and its introduction route might be from West Asia via South Asia and Southeast Asia along the Indian Ocean. [ABSTRACT FROM AUTHOR]

The long-term trend in satellite retrieved phytoplankton size classes (PSC) such as picophytoplankton (PP), nanophytoplankton (NP), and microphytoplankton (MP) was studied in the three zones falling under different ecological provinces in open ocean regions of the Arabian Sea. A regionally tuned three-component "abundance" model was used to compute PSC biomass from Moderate Resolution Imaging Spectroradiometer onboard Aqua (MODISA) satellite data for the period of 17 years (2003 to 2019). The overall trend indicated the highest concentration of all PSC in the northern Arabian Sea (ARAB province) which gradually decreased to the southern region (MONS province). All PSC biomass showed a peak during the winter monsoon period in ARAB province attributed to the recurring algal bloom. The long-term temporal trend showed relatively lower concentration (most of the times < 0.1 mg m−3) of all PSC biomass in MONS in comparison with ARAB. However, the monthly climatology of total phytoplankton biomass exhibited a similar pattern in all the provinces. The temporal distribution of the PSC biomass discerned rank order of MP > PP > NP in ARAB. In contrast, MONS displayed PSC rank order as PP > NP > MP. A sharp decline in the concentration of MP biomass was observed during the onset of summer monsoon period in comparison with other PSC in MONS. [ABSTRACT FROM AUTHOR]

In this project, scientists describe the processes by which a subsurface nearshore algal bloom is carried to the surface, swept closer to the shore and ultimately blocked from entering the surf zone at Huntington Beach in Orange County, California.

Prochlorococcus and Synechococcus are pico-sized cyanobacteria that play a fundamental role in oceanic primary production, being particularly important in warm, nutrient-poor waters. Their potential response to nutrient enrichment is expected to be contrasting and to differ from larger phytoplankton species. Here, we used a metagenomic approach to characterize the responses to nutrient enrichment in the community of picocyanobacteria and to analyze the cyanophage response during a mesocosms experiment in the oligotrophic Red Sea. Natural picoplankton community was dominated by Synechococcus clade II, with marginal presence of Prochlorococcus (0.3% bacterial reads). Increased nutrient input triggered a fast Synechococcus bloom, with clade II being the dominant, with no response of Prochlorococcus growth. The largest bloom developed in the mesocosms receiving a single initial input of nutrients, instead of daily additions. The relative abundances of cyanophage sequences in cellular metagenomes increased during the experiment from 12.6% of total virus reads up to 40% in the treatment with the largest Synechococcus bloom. The subsequent collapse of the bloom pointed to a cyanophage infection on Synechococcus that reduced its competitive capacity, and was then followed by a diatom bloom. The cyanophage attack appears to have preferentially affected the most abundant Synechococcus clade II, increasing the evenness within the host population. Our results highlight the relevance of host-phage interactions on determining population dynamics and diversity of Synechococcus populations.

Measurement of the spatial and temporal scales of nearshore chlorophyll-a (chl) is critical to our ability to understand or predict dense, and potentially harmful blooms of phytoplankton along the California Coast. Patchiness in chl may result from patchiness in nutrient availability, swimming or sinking, predation, or transport and mixing by breaking waves, currents, internal waves and tides. We performed a study during the Fall 2006 Huntington Beach (HB06) experiment to investigate the biological and physical factors that affect phytoplankton patchiness. Autotrophic phytoplankton require light and nutrients to survive. However, the nearshore euphotic zone (the critical depth for photosynthesis) is often nutrient-depleted due to uptake and planktonic growth. In order to sustain populations, phytoplankton rely on delivery of new nutrients from below the euphotic zone through upwellling or vertical mixing. or 2) terrestrial sources (from rain, ground water, tidal flushing or river outflow) that feed directly into the nearshore.

The past decades have seen an increasing interest on the biology of photosynthetic species living in aquatic environments, including diverse organisms collectively called “algae.” If we consider the relative size of scientific communities, marine and freshwater plants have been overall less studied than terrestrial ones. The efforts put on land plants were motivated by agriculture and forestry, applications for human industry, easy access to terrestrial ecosystems, and convenient cultivation methods in fields or growth chambers. By contrast, the fragmentary knowledge on the biology of algae, the hope to find in this biodiversity inspiration for biotechnologies, and the emergency created by the environmental crisis affecting oceans, lakes, rivers, or melting glaciers, have stressed the importance to make up for lost time. Needed efforts embrace a broad spectrum of disciplines, from environmental and evolutionary sciences, to molecular and cell biology. In this multiscale view, functional genomics and ecophysiology occupy a pivotal position linking molecular and cellular analyses and ecosystem-level studies. Without pretending to be exhaustive and with few selected references, six grand challenges, requiring multidisciplinary approaches, are introduced below.

Hydrozoa medusae undergo blooms and seasonal fluctuations; however the drivers of such fluctuations are unknown. To understand how medusa populations fluctuate in response to seasonal factors such as temperature, salinity, dissolved oxygen, and chlorophyll a, and to enhance our taxonomic knowledge of Hydrozoa in Galveston Bay (TX), we performed frequent plankton sampling from September 2015 to September 2016. We collected 1,321 medusae in 190 sampling days. Using molecular barcoding and morphological analyses we identified 25 species, of which 21 are a first record for Galveston Bay and eight for the Gulf of Mexico. Daily medusa abundance is non-linearly related to temperature, with peak abundance estimated with multivariate regression analysis at approximately 21C. The role that temperature plays in driving medusa abundance has implications for future climate change scenarios, given that temperature in the Gulf of Mexico is expected to rise 4 °C by the end of the century. We also show that the biodiversity of the Galveston Bay and the Gulf of Mexico is underestimated and that molecular barcoding is an important and efficient tool to identify large number of medusae. We conclude that dense plankton sampling is necessary to capture both diversity and abundance of planktonic medusae.

Memory is an active, subjective, intelligent reflection process of our previous experiences. Memory is the superior (logical or intellectual) cognitive process that defines the temporal dimension of our mental organization. It is our ability to encode, store, retain, and then recall information and past experiences. Bloom's taxonomy has long been regarded as the best cognitive theory. In the 1956 original version of the taxonomy, the cognitive domain is broken into the six levels of objectives listed below: Knowledge,Comprehension, Application, Analysis, Synthesis, Evaluation. According to this theory, memory was not predicted. Many facts deny this theory. The importance of memory is great not only for pupils in schools, students in colleges, but also in every day life. For example, how can we read if we do not remember the letters? How can you do a simple mathematical calculation, for example a simple multiplication (7x3 = 21) if you do not remember the multiplication table. If we do not have to keep in mind, do we have to carry the multiplication table with us wherever we go. How can you drive well if you do not remember the meaning of traffic signs, should we carry with us wherever we go the book of traffic signs. So according to Bloom's taxonomy, since we do not need to keep in mind, then we have to stop the car in front of every traffic sign, browse the traffic sign book, and act according to the sign. Imagine what traffic would develop in the world, ignoring memory, according to Bloom taxonomy. [ABSTRACT FROM AUTHOR]

In this study, it is aimed to examine the Science and Art Centers Turkish Course Curriculum (2020), according to the revised Bloom taxonomy. For this, the objectives in the program were determined and these objectives were evaluated in terms of cognitive domain steps and knowledge types determined in the revised Bloom's taxonomy. The study was designed in accordance with the case study preferred in qualitative research. Document analysis was used for data collection, and descriptive analysis method was used for data analysis. According to the findings; the objectives are most suitable for using factual and conceptual knowledge. Achievements corresponding to remembering and understanding from the cognitive domain steps stand out as a percentage. According to the results, knowledge types and cognitive domain levels are not distributed evenly. Among the types of knowledge, the objectives using procedural and metacognitive knowledge are relatively inadequate. While the lower levels come to the fore in the stages of remembering and comprehension, the objectives corresponding to the upper level stages of analysis, evaluation and creation were not included enough in the program. Gifted students need to think critically and analytically, and to recognize and develop their abilities. In this respect, it is recommended to ensure a balanced distribution in the programs to be developed, to include the objectives appropriate to the analysis, evaluation and creation steps related to the type of metacognitive knowledge and high-level cognitive skills. [ABSTRACT FROM AUTHOR]

This study presents the unusual mass mortality of Rhizostoma pulmo occurred on the coast of İstanbul in the Sea of Marmara in the first week of December 2020. The density of dead R. pulmo was 45±5 ind./m2 in the area and the mean diameter was 24.3 cm. The role of physical parameters, marine pollution, nutrient influx, climate change, overfishing, invasive species on jellyfish blooms and its effect on human health are discussed briefly in this study. [ABSTRACT FROM AUTHOR]

Nowadays, more-and-more cyber-security training is emerging as an essential process for the lifelong personnel education in organizations, especially for those which operate critical infrastructures. This is due to security breaches on popular services that become publicly known and raise people's security awareness. Except from large organizations, small-to-medium enterprises and individuals need to keep their knowledge on the related topics up-to-date as a means to protect their business operation or to obtain professional skills. Therefore, the potential target-group may range from simple users, who require basic knowledge on the current threat landscape and how to operate the related defense mechanisms, to security experts, who require hands-on experience in responding to security incidents. This high diversity makes training and certification quite a challenging task. This study combines pedagogical practices and cyber-security modelling in an attempt to support dynamically adaptive training procedures. The training programme is initially tailored to the trainee's needs, promoting the continuous adaptation to his/her performance afterwards. As the trainee accomplishes the basic evaluation tasks, the assessment starts involving more advanced features that demand a higher level of understanding. The overall method is integrated in a modern cyber-ranges platform, and a pilot training programme for smart shipping employees is presented. [ABSTRACT FROM AUTHOR]

• The present study identified the present of two biological active compounds in the methanolic extract of the secondary metabolites of Microcystis aeruginosa. • Benzeneacetanomide and Norvaline, n-propargyloxycarbonyl is the two biological compounds present in the methanolic extract of Microcystis aeruginosa secondary metabolites. • Antibacterial, antioxidant and anticancer activity of Benzeneacetanomide and Norvaline, n-propargyloxycarbonyl mixture was screened. • Benzeneacetanomide and Norvaline, n-propargyloxycarbonyl mixture shows well notified Antibacterial, antioxidant and anticancer activity. The biomedical applications of the secondary metabolites produced by the harmful algal blooms were studied over a few decades ago. Only few research studies have been reported on the medicinal properties of the secondary metabolites produced by the cyanobacteria Microcystis aeruginosa. The present study was aimed to screen the Biological activities of GC fractionated Benzeneacetanomide and Norvaline, n-propargyloxycarbonyl mixtures of Microcystis aeruginosa secondary metabolites. The Microcystis aeruginosa samples were collected by plankton net from the blooming area at Muttukadu. The metabolites were extracted by using polar solvent as methanol. The yield percentage of Microcystis aeruginosa methanolic extract showed moderate level of 41% from the dry weight of the pre extracted Microcystis aeruginosa powder. The crude metabolites were purified through column chromatography and GC-MS analysis. The GC-MS results showed the presence of two compounds (2 major peaks), Benzeneacetamide at the retention time (RT) of 7.315 min and l-Norvaline, n-propargyloxycarbonyl (Pyrrol derivaties) at the retention time (RT) of 12.541 min. The GC-MS fractioned compounds were characterized by FT-IR and 1HNMR. The anticancer, antioxidant and antimicrobial activity of the compounds were studied. This study highlights the bioactive potential of Microcystis aeruginosa secondary metabolites that might lead to the development of cancer drug. [ABSTRACT FROM AUTHOR]

The coral reefs of French Polynesia (FP) have experienced repeated macroalgal blooms over the last decades. These events have prompted intense efforts in fundamental and applied research on macroalgae in this ecoregion, especially regarding species of the order Fucales (Turbinaria ornata and Sargassum pacificum). Recently, however, these proliferations have occurred with a higher frequency, and they now involve additional species. Specifically, over the past decade, the abundance of species belonging to the Dictyotaceae family (e.g., Dictyota bartayresiana and Spatoglossum asperum) has increased on coral reefs around Tahiti Island, the largest and most inhabited island in FP. On the course of evolution, these species have developed physical and chemical defenses to deter grazers, including the production of a wide array of specialized metabolites. These molecules are of particular interest for their promising biological activities as well as for the new Blue Economy opportunities they can offer to FP. We review the current state of knowledge on the diversity, ecology, and potential uses of Dictyotaceae species present in FP. The first section focuses on the diversity and distribution of the family Dictyotaceae in FP. The second part examines the ecological dynamics of Dictyotaceae species in the coral reef ecosystem and their response to various environmental factors. The third and final part reviews the metabolites known from Dictyotaceae species that are present in FP, their associated biological activities, and potential for the development of biotechnological applications in FP. [ABSTRACT FROM AUTHOR]

Walt Whitman is known mainly as a poet, as one of the great poets that gave the New America of the nineteenth century. But in 1871 he wrote Democratic Perspectives, a text that despite having a poetic language, is a clear manifestation of his political thought. We will take this essay as a reference to provide a reading that will bring us closer to the political thinking of the author and, in addition, we will go to other authors, other Whitman texts and our own understanding to complete the writing. [ABSTRACT FROM AUTHOR]

Blooms of toxin‐producing cyanobacteria have been more frequent and lasting because of the eutrophication of freshwater ecosystems, including those used for aquaculture. The aim of the present study was to investigate the effects of chronic exposure to a saxitoxin‐producing strain of Raphidiopsis (Cylindrospermopsis) raciborskii on the performance of Nile tilapia (Oreochromis niloticus) fingerlings over a 60‐d period. The fingerlings were cultivated under the following conditions: 1) water without cyanobacterium (WATER), 2) R. raciborskii in ASM‐1 culture medium (CYANO), and 3) ASM‐1 culture medium without cyanobacterium (ASM). Exposure to the CYANO treatment led to a significant increase in the mortality rate (p < 0.05) and a significant reduction in growth (p < 0.05) compared to fingerlings submitted to the ASM and WATER treatments, in which similar survival and growth were found (p > 0.05). Saxitoxin toxicity was dependent on the weight of the fingerling (p < 0.05), with maximum mortality caused by the ingestion of 13.66 μg saxitoxin equivalent L−1 g−1. The present results clearly show the harm caused by saxitoxins to the production of Nile tilapia fingerlings in the early growth phase. These findings underscore the importance of maintaining adequate water quality in aquaculture activities to minimize the risk of saxitoxin‐producing cyanobacterial blooms and avoid economic losses among producers. Environ Toxicol Chem 2020;39:1409–1420. © 2020 SETAC [ABSTRACT FROM AUTHOR]

Prochlorococcus and Synechococcus are pico-sized cyanobacteria that play a fundamental role in oceanic primary production, being particularly important in warm, nutrient-poor waters. Their potential response to nutrient enrichment is expected to be contrasting and to differ from larger phytoplankton species. Here, we used a metagenomic approach to characterize the responses to nutrient enrichment in the community of picocyanobacteria and to analyze the cyanophage response during a mesocosms experiment in the oligotrophic Red Sea. Natural picoplankton community was dominated by Synechococcus clade II, with marginal presence of Prochlorococcus (0.3% bacterial reads). Increased nutrient input triggered a fast Synechococcus bloom, with clade II being the dominant, with no response of Prochlorococcus growth. The largest bloom developed in the mesocosms receiving a single initial input of nutrients, instead of daily additions. The relative abundances of cyanophage sequences in cellular metagenomes increased during the experiment from 12.6% of total virus reads up to 40% in the treatment with the largest Synechococcus bloom. The subsequent collapse of the bloom pointed to a cyanophage infection on Synechococcus that reduced its competitive capacity, and was then followed by a diatom bloom. The cyanophage attack appears to have preferentially affected the most abundant Synechococcus clade II, increasing the evenness within the host population. Our results highlight the relevance of host-phage interactions on determining population dynamics and diversity of Synechococcus populations. [ABSTRACT FROM AUTHOR]

The impact of environmental variables and processes of nutrient enrichment on phytoplankton community at Epe lagoon was studied for 18 months (November 2012–April 2014). Two cyanobacterial bloom incidences were observed in the two dry seasons during this period. Rainfall pattern regulated nitrogen limitation which triggered cyanobacterial bloom development and influenced the bloom duration. Nutrient-laden influx from agricultural practices accounted for the increase in nitrate, phosphate and the relatively low silicate. Hypoxic conditions during the two bloom episodes reflected the vulnerability of this lagoon ecosystem. The cyanobacterial blooms were dominated by potentially toxic species; Anabaena circinalis, A. flos-aquae, A. limnetica and A. spiroides. A comparison of ambient nutrient ratios with the Redfield ratio (N/P/Si = 16:1:16) showed clear temporal variations that coincided with phytoplankton dynamics and the bloom regime. Low N/P ratios were recorded during the first 8 months, and there was a shift to higher ratios during the subsequent 8 months, followed by low N/P ratios in the last 2 months. Higher silicate values coincided with decreased cyanobacterial biomass, cyanobacteria bloom collapse and proliferation of diatoms during the first annual cycle. Cyanobacterial abundance exceeded the alert level 1 and almost reached alert level 2 which call for continuous environmental monitoring and management of coastal waters. [ABSTRACT FROM AUTHOR]

Aiming at the problem of negative segregation under a bloom surface, a coupling macrosegregation model considering electromagnetic field, flow, heat, and solute transport was established based on the volume average method to study the effect of in-mold electromagnetic stirring (M-EMS) on the negative segregation under the bloom surface. In the model, the influence of dendrite structure on the flow and solute transport was described by the change of permeability. The model was validated by the magnetic induction intensity of M-EMS and carbon segregation experiment. The results show that the solute C in the solidified shell in the turbulent zone of the bloom undergoes two negative segregations, whereby the first is caused by nozzle jet, and the second by the M-EMS. The severities of the negative segregation caused by M-EMS at different currents and frequencies are also different, and the larger the current is, or the smaller the frequency is, the more serious will be the negative segregation. With the M-EMS, the solute C distribution in the liquid phase of the bloom is more uniform, but the mass fraction of C in the liquid phase is higher than that without M-EMS. [ABSTRACT FROM AUTHOR]

The annual episodes of high-biomass algal bloom are a known phenomenon in the northern Arabian Sea. In the present study, we demonstrate growth and decay of bloom using long-term satellite-retrieved parameters such as chlorophyll-a (chl-a), sea surface temperature (SST), phytoplankton absorption (aph), detritus–coloured dissolved organic matter absorption (adg) and model-derived mixed layer depth (MLD). Chl-a, the index of phytoplankton biomass, showed an inverse relationship with SST with a lag of 2–8 days between lowest SST and highest chl-a. The deepening of MLD associated with high chl-a and low SST indicated a role of convective mixing in the formation of bloom. The average SST of ~ 25 °C was found to be a favourable condition for such open ocean bloom. The lag was more towards eastern boundary of the basin, indicating variable intensities of convective mixing influencing spatial extent of bloom. The positive correlation between aph and adg indicated simultaneous production and degradation showing delay of 3–10 days from peak production to degradation. [ABSTRACT FROM AUTHOR]

Web 2.0 tools are used increasingly in many institutions to promote learning but there is insufficient guidance about how to design and analyze online activities. This paper is based on an interactive platform aimed at enhancing students' learning of French beyond the classroom. It will focus on a model that has been developed to facilitate the creation of online activities. This model accounts for the role of the teacher, the learner and the technology, as part of a holistic approach to ensure the effectiveness of learning. The paper concludes by examining the importance of applying this model in a flexible way and provides recommendations to educators. [ABSTRACT FROM AUTHOR]

The long-term distribution of in situ optically active substances (OAS), accuracy assessment of satellite retrieved chlorophyll-a (chl-a) and its long-term trend has been carried out at a coastal site of the north-western Bay of Bengal. The temporal distribution of chl-a, total suspended matter (TSM) and absorption due to coloured dissolved organic matter at 440 nm (aCDOM440) discerned a common peak during southwest monsoon season (August–October). Chl-a also showed a prominent peak during pre-southwest monsoon period (March–April). The spatial variability of TSM and aCDOM440 was maximum during southwest monsoon, whereas in the case of chl-a, it was during pre-southwest monsoon. The accuracy assessment of chl-a retrieved from Moderate Resolution Imaging Spectroradiometer-Aqua (MODISA), Ocean Colour Monitor-2 (OCM-2) and Visible Infrared Imager Radiometer Suite (VIIRS) showed overestimation in nearshore waters. The error in satellite measurement of chl-a was within the range of 33 to 51%. The chl-a retrieved from MODISA was most accurate as indicated by statistical analysis. The long-term trend in satellite chl-a clearly indicated bi-modal distribution with a primary peak during pre-southwest monsoon attributed to recurrent phytoplankton bloom that was mostly confined to nearshore waters. Whereas, the secondary peak in chl-a, during the end of southwest monsoon, spreads far offshore. [ABSTRACT FROM AUTHOR]

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This study presents the first record of Lychnorhiza malayensis Stiasny, 1920, in Malaysian waters since its first discovery in the Java Sea of Indonesia nearly a century ago. Better representation of the species was achieved by the collection of more specimens than previous studies. Thirteen specimens were collected from the midwestern and northeastern coasts of Peninsular Malaysia and their morphology was examined in detail. Morphological descriptions of L. malayensis from outside Malaysia and our collection in Malaysia were compared, reviewed and updated. All Lychnorhiza species were also compared and differences highlighted. Lychnorhiza malayensis can be distinguished from its congeners primarily by the presence of subumbrellar papillae, higher counts of the centripetal canal which tends to anastomose, and the distinctive colour patterns and markings of the umbrella. Intraspecific variations were observed among specimens in terms of different papillae and centripetal canal forms, inter-rhopaliar canals that extend beyond or terminating at the circular canal, various colour patterns and markings, the number of velar lappets and size (length and width) of oral arms that were also different from previous descriptions. The morphological redescription of this species will facilitate the identification of this bloom-forming species and contribute to the inventories of marine biological resources in Malaysia. [ABSTRACT FROM AUTHOR]

Didymosphenia geminata is a bloom-forming diatom that has invaded numerous temperate rivers globally. Proliferations of D. geminata can result in negative effects on invaded communities. Ecological theory suggests impacts may vary associated with trait variation in both invaded communities and the invader. Trait commonalities related to organism size are rarely considered, yet are expected to influence the outcomes of ecological (niche and neutral) processes and invader effects. We hypothesised that D. geminata would impact diversity and community composition, with effects varying between size classes, influenced by niche and spatial gradients. To examine this hypothesis, we surveyed 55 rivers along a gradient of D. geminata biomass in the South Island, New Zealand, collecting data on algal and invertebrate communities, 33 spatial predictors, and 111 physical and chemical predictors. Didymosphenia geminata biomass was associated with increased species richness in both algal and invertebrate assemblages, but blooms reduced beta-diversity resulting in more homogenous communities. Both niche and neutral processes influenced community assembly and invader effects, which varied between algae and invertebrates. However, D. geminata appeared to have a dominant influence on both communities, irrespective of organism size. These findings reinforce the substantial negative effect invasive species such as D. geminata can cause in invaded ecosystems. [ABSTRACT FROM AUTHOR]

The researches were carried out in the orchard of the company "Agroparc Management" LLC, during the years 2017-2019. The object of the research was the apricot trees Wonder Cot, Spring Blush, Magic Cot, Lilly Cot, Pinkcot, Perle Cot, Orange Red, Sweet Cot, Big Red, Kyoto, Faralia and Farbaly varieties, grafted on the rootstock Mirobalan 29C. Planting distance 5.0 x 3.0 m. Apricot trees were planted in the spring of 2015. During the research we studied the period of onset of the phases beginning to bloom and the maturation of fruit harvest, the period between these two phases at various apricot varieties. It was established that the biological particularities of the variety influence the period of onset of the beginning of flowering phases and the maturation of apricot fruit harvest, the period between these two phases. [ABSTRACT FROM AUTHOR]

Extension educators today face several challenges in designing, delivering, and evaluating programs. Achieving successful program outcomes is becoming increasingly difficult. Educators must choose amongst a wide variety of technology and delivery methods, all while facing resource constraints such as cost, time, and materials. Educators require a tool that helps them to select delivery methods that achieve more successful program outcomes. We developed a conceptual model that connects the scholarly works of Bloom et al., Dale, and Bennett with over 30 program delivery methods. This article demonstrates the model’s utility by applying it to a past program on smoking cessation.

Oil spills in oceans have substantial influence on marine ecosystems. This study investigates 21 oil spills in the world. Analyzing Chlorophyll-a (Chl-a) from Moderate Resolution Imaging Spectroradiomerer (MODIS) data after Penglai oil spills on 4 June 2011, found a bloom with peak value of Chl-a (13.66 mg m−3) spread over an area of 800 km2 during 18–25 June 2011, and a pronounced increase in the monthly Chl-a concentration (6.40 mg m−3) on June 2012 in the Bohai Sea. Out of the 21 oil spills, 14 blooms were observed, while 11 blooms associated with oil spills in the time interval of 3–10 months. In total, about 75% blooms occurred during June–August. Among all 14 blooms, 72% appeared when temperature was warm (20–30 °C), 7% appeared when temperature was low (10–20 °C), and the remaining 21% occurred when temperature was lower than 10 °C. This research concludes that the odds of a phytoplankton bloom after an oil spillage are higher at the time of higher temperature (>20 °C). The short-term impact of the oil spills on ecosystem could mainly depend on the quantity and composition of oil, while the long-term impact of the oil spills on ecosystem could be related to biodegradation of microorganisms. [ABSTRACT FROM AUTHOR]

We carried out shipboard observations in Funka Bay, Hokkaido, Japan, monthly or bimonthly from December 2015 to November 2016. We measured vertical profiles of isoprene, chlorophyll-a (chl-a), and other parameters from surface to bottom layer (about 95 m) near the center of the bay. We found substantial increases in isoprene concentration in the surface mixed layer from February to March during the peak of the spring diatom bloom, in the bottom layer from March to April after the peak of the bloom, and in the subsurface layer (below the surface mixed layer) in summer from July to August, where there were also substantial chl-a concentration maxima. We attribute the increased isoprene in the surface and subsurface layers to photosynthetic production of isoprene by the dominant phytoplankton in the spring bloom and in summer, and that in the bottom layer to dark production of isoprene by diatom aggregates that settled from the surface euphotic zone. We also measured isoprene production in laboratory incubation experiments. The rates of in situ production of isoprene per unit chl-a in the surface mixed layer during the spring bloom, in the dark bottom layer during the bloom, and in the subsurface layer in summer (0.82, 0.03–0.13, and 7.38 pmol (μg chl-a)−1 day−1, respectively) were consistent with our incubation results. We believe that this is the first report focused on dark production of isoprene by diatoms; the rate of isoprene production under dark conditions ranged from 4% to 16% of that by photosynthesis. [ABSTRACT FROM AUTHOR]

The past decades have seen an increasing interest on the biology of photosynthetic species living in aquatic environments, including diverse organisms collectively called "algae." If we consider the relative size of scientific communities, marine and freshwater plants have been overall less studied than terrestrial ones. The efforts put on land plants were motivated by agriculture and forestry, applications for human industry, easy access to terrestrial ecosystems, and convenient cultivation methods in fields or growth chambers. By contrast, the fragmentary knowledge on the biology of algae, the hope to find in this biodiversity inspiration for biotechnologies, and the emergency created by the environmental crisis affecting oceans, lakes, rivers, or melting glaciers, have stressed the importance to make up for lost time. Needed efforts embrace a broad spectrum of disciplines, from environmental and evolutionary sciences, to molecular and cell biology. In this multiscale view, functional genomics and ecophysiology occupy a pivotal position linking molecular and cellular analyses and ecosystem-level studies. Without pretending to be exhaustive and with few selected references, six grand challenges, requiring multidisciplinary approaches, are introduced below. [ABSTRACT FROM AUTHOR]

Based on the field surveys aimed at understanding the variations of Synechococcus (Syn) abundance in the Pearl River Estuary during different seasons. We found that heavy terrestrial precipitation result in significant riverine runoffs and promote Syn growth, extension and blooms during warm and wet seasons. To understand the ecological role of Syn play in this estuary during wet seasons, we combined flow cytometry and high throughput sequencing (HTS) of 16S rDNA to investigate the phytoplankton distribution patterns and the potential shaping mechanisms during a typical wet season. During the cruise, picophytoplankton, especially Syn, and Nano-eukaryotes contributed importantly to the total phytoplankton biomass of the estuary. Syn can be further divided into phycoerythrin (PE)-rich Syn and phycocyanin (PC)-rich Syn, with PC-rich Syn about 1.5 times higher than PE-rich Syn in abundance. Both PE-rich Syn (60.75 × 103 cells ml−1) and PC-rich Syn (604.05 × 103 cells ml−1) reach the highest abundance at the lower part of the estuary. Moreover, PE-rich Syn can be divided into two subgroups which showed different salinity preference, with PE1 distributed in the high salinity area (with salinity >25) while PE2 in the middle salinity area (with salinity 7–20). Our results from the 16S rDNA sequencing also indicated abundant diversity and different niche adaptation of Syn with the operational taxonomic units (OTUs) along the estuary. Besides, analysis also indicated a tight correlation between estuarine Syn and active heterotrophic bacteria, especially groups of Rhodobacteria and Actionobacteria. Unlabelled Image • Small phytoplankton, especially Synechococcus and nanoeukaryotes, contribute to the blooms in the lower Pearl River Estuary. • Phycocyanin-rich Synechococcus have wide salinity tolerances and occur in high abundance in the lower estuary. • The two groups of phycoerythrin-rich Synechococcus have different salinity tolerances. • Different niche segregation among picocyanobacterial clades can be identified from the OTUs of 16S rDNA. • Synechococcus blooms show close interactions with active bacteria, particularly for Rhodobacteria and Actinobacteria. [ABSTRACT FROM AUTHOR]

While light limitation can inhibit bloom formation in dinoflagellates, the potential for high‐intensity photosynthetically active radiation (PAR) to inhibit blooms by causing stress or damage has not been well‐studied. We measured the effects of high‐intensity PAR on the bloom‐forming dinoflagellates Alexandrium fundyense and Heterocapsa rotundata. Various physiological parameters (photosynthetic efficiency Fv/Fm, cell permeability, dimethylsulfoniopropionate [DMSP], cell volume, and chlorophyll‐a content) were measured before and after exposure to high‐intensity natural sunlight in short‐term light stress experiments. In addition, photosynthesis‐irradiance (P‐E) responses were compared for cells grown at different light levels to assess the capacity for photophysiological acclimation in each species. Experiments revealed distinct species‐specific responses to high PAR. While high light decreased Fv/Fm in both species, A. fundyense showed little additional evidence of light stress in short‐term experiments, although increased membrane permeability and intracellular DMSP indicated a response to handling. P‐E responses further indicated a high light‐adapted species with Chl‐a inversely proportional to growth irradiance and no evidence of photoinhibition; reduced maximum per‐cell photosynthesis rates suggest a trade‐off between photoprotection and C fixation in high light‐acclimated cells. Heterocapsa rotundata cells, in contrast, swelled in response to high light and sometimes lysed in short‐term experiments, releasing DMSP. P‐E responses confirmed a low light‐adapted species with high photosynthetic efficiencies associated with trade‐offs in the form of substantial photoinhibition and a lack of plasticity in Chl‐a content. These contrasting responses illustrate that high light constrains dinoflagellate community composition through species‐specific stress effects, with consequences for bloom formation and ecological interactions within the plankton. [ABSTRACT FROM AUTHOR]

The last 12 years has seen the dominance of Ulva prolifera in the green tides occurring in the Yellow Sea. To gain a better understanding of the underlying molecular clues associated with the dominance pattern of the Yellow Sea green tides, we generated and compared the transcriptomes of four co-occurring Ulva species including U. prolifera, U. linza, U. flexuosa, and U. compressa under the same conditions. Our results revealed that the transcriptomes of four Ulva species shared a set of core genes, but varied in construction of GO term categories, transcription factor (TF) styles, and metabolism pathways. Based on the KEGG database, several growth-related genes including pyruvate kinase (PK) and nitrate transporter (NRT) have been identified to be enriched in U. prolifera compared with the other three Ulva species. This study provides novel transcriptionomic data for us to understand the species dominance pattern in the Yellow Sea green tides. [ABSTRACT FROM AUTHOR]

In this paper, an ensemble-based system (EBS) for estimating chlorophyll-a concentrations (Chl-a) in inland water bodies using downscaled MODIS images was developed. Seeking additional opinions before making a decision is part of human nature, particularly for decisions involving health issues. The general concept behind EBS algorithms is based on this principle. Forty-six Chl-a measurements, collected over four water bodies between 2000 and 2008, were used to calibrate the EBS. Measurements ranged from 2.7 (oligotrophic waters) to 91 000 mg Chl-a $\text{m}^{{-3}}$ (hypertrophic waters). The EBS performance was evaluated by cross validation, and also using an independent database (Chl-a ranging from 1 to 14 mg $\text{m}^{{-3}}$). Cross-validation results were satisfactory both under high-blooming conditions ($\text{R}^{2} = 0.98$ , relative RMSE (RMSEr) = 15%, relative Bias (BIASr) = −2%, and relative Nash (NASHr) = 0.95) and at the initialization of blooms ($\text{R}^{2} = 0.77$ , RMSEr = 37%, BIASr = −8%, and NASHr = 0.70). The EBS also performed well on the independent database ($\text{R}^{2} =0.93$ , RMSEr = 50%, BIASr = −27%, and NASHr = 0.70). A visual comparison mapping Chl-a on the Missisquoi Bay of Lake Champlain additionally illustrates the potential of the EBS to detect early phases of algal growth contrary to other models (adaptive model, Kharu, and APProach by Elimination). This approach is a proof of concept for a more efficient way to quantify algal biomass from remote sensing and could be exported to any types of satellite imagery in a context of water quality monitoring. [ABSTRACT FROM AUTHOR]

Hydrozoa medusae undergo blooms and seasonal fluctuations; however the drivers of such fluctuations are unknown. To understand how medusa populations fluctuate in response to seasonal factors such as temperature, salinity, dissolved oxygen, and chlorophyll a, and to enhance our taxonomic knowledge of Hydrozoa in Galveston Bay (TX), we performed frequent plankton sampling from September 2015 to September 2016. We collected 1,321 medusae in 190 sampling days. Using molecular barcoding and morphological analyses we identified 25 species, of which 21 are a first record for Galveston Bay and eight for the Gulf of Mexico. Daily medusa abundance is non-linearly related to temperature, with peak abundance estimated with multivariate regression analysis at approximately 21C. The role that temperature plays in driving medusa abundance has implications for future climate change scenarios, given that temperature in the Gulf of Mexico is expected to rise 4 °C by the end of the century. We also show that the biodiversity of the Galveston Bay and the Gulf of Mexico is underestimated and that molecular barcoding is an important and efficient tool to identify large number of medusae. We conclude that dense plankton sampling is necessary to capture both diversity and abundance of planktonic medusae. [ABSTRACT FROM AUTHOR]

• Multiple techniques are used to report the diet of Noctiluca scintillans. • Noctiluca scintillans diet comprises at least 37 plankter families. • Copepods, diatoms, dinoflagellates, and picophytoplankton dominate the diet of N. scintillans. Red Noctiluca scintillans is a common heterotrophic dinoflagellate that forms blooms in temperate, subtropical, and tropical coastal ecosystems. The diet of this species plays an important role in its cell growth, development, and reproduction. Because limited gene diversity data are available regarding prey of this species, its diet in Daya Bay during a boreal winter bloom is reported using an integrated approach involving light microscopy, single cell isolation and plastid 16S rDNA cloning, and 18S rDNA V4 and V9 region amplification using isolated cells and environmental DNA as templates with high-throughput sequencing. While conventional light microscopy reveals the diet of this species to comprise Coscinodiscus sp. and Stephanopyxis turris (diatoms), copepod eggs, and detritus, plastid gene diversity identifies a diet comprising diatoms, cyanobacteria, and bacteria, and 18S rDNA high-throughput sequencing reveals a diet comprising 36 eukaryote families (primarily copepods, as well as diatoms, dinoflagellates, Ochrophyta, Haptophytes, Chordata, Cercozoans, Chlorophyta, Polychaeta, and ciliates). Dietary staples include copepods, diatoms, dinoflagellates, Ochrophyta, and Synechococcus. High copepod abundance in prey may reflect their relatively high abundance in environmental seawater. Thus, N. scintillans is generally omnivorous but prefers dominant phytoplankton taxa, including Rhizosoleniaceae, Leptocylindraceae, and Cymatosiraceae (diatoms), as well as Gonyaulacaceae (dinoflagellates). An integrated multi-disciplinary approach provides a more comprehensive picture of N. scintillans diet in Daya Bay, and an improved understanding of this species' ecological niche and trophic role in marine ecosystems. [ABSTRACT FROM AUTHOR]

Almond is an important tree nut crop worldwide, and planted areas have been increasing year after year. While self-fertility is one of the key factors when it comes to improved almond productivity of new cultivars, yield is also affected by the number of flowers produced, pollination, fruit set, fruit drop, and fruit weight. Almond fruit drop patterns of 20 Mediterranean almond cultivars were studied over three years. In addition, fruit drop patterns of two scion cultivars ‘Marinada’ and ‘Vairo’ budded onto eight to 10 different rootstocks managed with three different pruning strategies were studied for two years. Cumulative flower and fruit drop ranged from 50% to 90% among cultivars and treatments, and there were up to four fruit drop events during the growing season, the main one occurring from 20–60 days from full bloom (DFFB). Subsequent drops were at 100 DFFB, 120–140 DFFB, and the last one at 160–180 DFFB. The later drops were less apparent. In general, about half of the cumulative drop was comprised of buds and flowers, and the remaining percentage was fruit that dropped 20 or more days after full bloom. Furthermore, different fruit drop patterns were observed depending on the cultivar. For late- and extra-late flowering cultivars, cumulative fruit drop began to decrease earlier, with most of the drops occurred already at full bloom, whereas the opposite was observed for the early flowering cultivars. Rootstocks also had an important effect on the fruit drop pattern, with different effects depending on the scion cultivar. Tree management, such as type of pruning, also had an important effect on the rate of fruit drop and cumulative drop. Therefore, each combination of cultivar × rootstock × pruning type will require different strategies in order to reduce the fruit drop and optimize crop loads.

Bumble bees are among the most effective pollinators in orchards during the blooming period, yet they are often threatened by the high levels of pesticide use in apple production. This study aimed to evaluate the influence of landscape enhancements (e.g., hedgerows, flower strips) on bumble bee queens in apple orchards. Bumble bee queens from 12 orchards in southern Québec (Canada) were marked, released, and recaptured in the springs and falls of 2017 to 2019. Half of the 12 orchards had landscape enhancements. Apples were harvested in 2018 and 2019 to compare their quality (weight, diameter, sugar level, and seed number) in sites with and without landscape enhancements. Species richness, as well as the occurrence of three species out of eight, was higher in orchards with landscape enhancements than in orchards without such structures. The occurrence of Bombus ternarius was lower in orchards with high levels of pesticide use. Apples had fewer seeds when collected in orchards with landscape enhancements and were heavier in orchards that used more pesticides. Our work provides additional evidence that landscape enhancements improve bumble bee presence in apple orchards and should therefore be considered as a means to enhance pollination within farms.

This review aimed to summarize original and published data on the bloom events caused by toxic diatoms of the genus Pseudo-nitzschia and to assess long-term variations in the composition of bloom-forming species in the northwestern Sea of Japan during 1992−2015. This information is crucial to understanding the potential threat of toxic blooms and their effects. A change in species composition was observed within the genus Pseudo-nitzschia: it was dominated by Pseudo-nitzschiamultiseries during 1992–1993, 2002, and a shift towards the dominance of Pseudo-nitzschiamultistriata and Pseudo-nitzschiacalliantha occurred in 2005–2015. We assume that the increased sea surface temperature recorded from Amursky Bay in the period of 1998–2009 compared to the data of 1980–1989 might be one of the causative factors for the shift observed. The absence of highly toxic Pseudo-nitzschiamultiseries among the bloom-forming species is considered as one of the possible explanations for the lack of damage from the blooms of Pseudo-nitzschia over the past 15 years in the study area.