Effectiveness of hierarchical Bayesian models for citizen science data with missing values: A case study on the factors influencing beach litter in Shimane Prefecture, Japan.

Citizen science can play an important role in addressing the issue of marine debris. However, citizen science data are often composed of inconsistent methods compared to data collected by experts. In this study, we applied beach cleanup data, collected in different survey years at different survey sites, to a hierarchical Bayesian model to elucidate the factors affecting the distribution of beach litter. The results showed the model accounting for differences between years had a smaller Watanabe-Akaike Information criterion than the model that did not account for it, indicating better accuracy of the model. The amount of beach litter was influenced by current velocity and bay openness, and these effects varied across years. The results indicate that citizen science data, which may contain missing values due to various constraints such as economic and human resources, can make an important contribution toward solving marine debris issues by flexible statistical analysis methods.

Foraminifera and plastic pollution: Knowledge gaps and research opportunities.

Plastic has become one of the most ubiquitous and environmentally threatening sources of pollution in the Anthropocene. Beyond the conspicuous visual impact and physical damages, plastics both carry and release a cocktail of harmful chemicals, such as monomers, additives and persistent organic pollutants. Here we show through a review of the scientific literature dealing with both plastic pollution and benthic foraminifera (Rhizaria), that despite their critical roles in the structure and function of benthic ecosystems, only 0.4% of studies have investigated the effects of micro- and nano-plastics on this group. Consequently, we urge to consider benthic foraminifera in plastic pollution studies via a tentative roadmap that includes (i) the use of their biological, physiological and behavioral responses that may unveil the effects of microplastics and nanoplastics and (ii) the evaluation of the indicative value of foraminiferal species to serve as proxies for the degree of pollution. This appears particularly timely in the context of the development of management strategies to restore coastal ecosystems.

Environmental impact of removal of a large-scale sluice gate on Nakaumi Lagoon and adjacent coastal waters, southwest Japan: Evidence from long-term foraminiferal monitoring.

A large-scale sluice gate, which was built in southwest Japan as a national project to reclaim and desalinate lagoon water in 1974, was removed between 2005 and 2009. To examine the impact of this removal on both Nakaumi Lagoon and the nearby coastal waters, we analyzed the foraminiferal assemblages of a coastal sediment core and of samples obtained during 10 years of lagoon monitoring (2001-2010). Detailed 210Pb(ex) dating of the sediment core revealed an increased sediment accumulation rate in the coastal waters, implying that discharge of fine-grained materials, including organic matter, was facilitated by removal of the sluice gate. The observed increase in agglutinated foraminifera and decrease in calcareous species was related to the sediment accumulation rate, and these changes occurred close to 2005, when sluice-gate removal began. In Nakaumi Lagoon, the sporadic presence of the coastal species Quinqueloculina seminula within the 6-m water column and the decline in the lagoon-adapted Ammonia "beccarii" have occurred since 2005. The removal of the sluice gate, plus the sea-level rise, allowed greater seawater inflow and stabilized the monthly deep-water salinity fluctuations in Nakaumi Lagoon.

Relative abundances of benthic foraminifera in response to total organic carbon in sediments: Data from European intertidal areas and transitional waters.

We gathered total organic carbon (%) and relative abundances of benthic foraminifera in intertidal areas and transitional waters from the English Channel/European Atlantic Coast (587 samples) and the Mediterranean Sea (301 samples) regions from published and unpublished datasets. This database allowed to calculate total organic carbon optimum and tolerance range of benthic foraminifera in order to assign them to ecological groups of sensitivity. Optima and tolerance range were obtained by mean of the weighted-averaging method. The data are related to the research article titled "Indicative value of benthic foraminifera for biomonitoring: assignment to ecological groups of sensitivity to total organic carbon of species from European intertidal areas and transitional waters" [1].

Indicative value of benthic foraminifera for biomonitoring: Assignment to ecological groups of sensitivity to total organic carbon of species from European intertidal areas and transitional waters.

This work contributes to the ongoing work aiming at confirming benthic foraminifera as a biological quality element. In this study, benthic foraminifera from intertidal and transitional waters from the English Channel/European Atlantic coast and the Mediterranean Sea were assigned to five ecological groups using the weighted-averaging optimum with respect to TOC of each species. It was however not possible to assign typical salt marsh species due to the presence of labile and refractory organic matter that hampers TOC characterization. Tests of this study species' lists with Foram-AMBI on two independent datasets showed a significant correlation between Foram-AMBI and TOC, confirming the strong relation between foraminifera and TOC. For one of the validation datasets, associated macrofaunal data were available and a significant correlation was found between the foraminiferal Foram-AMBI and the macrofaunal AMBI. The here proposed lists should be further tested with sensitivity-based indices in different European regional settings.

Resonantly Enhanced Emission from a Luminescent Nanostructured Waveguide.

Controlling the characteristics of photon emission represents a significant challenge for both fundamental science and device technologies. Research on microcavities, photonic crystals, and plasmonic nanocavities has focused on controlling spontaneous emission by way of designing a resonant structure around the emitter to modify the local density of photonic states. In this work, we demonstrate resonantly enhanced emission using luminescent nanostructured waveguide resonance (LUNAR). Our concept is based on coupling between emitters in the luminescent waveguide and a resonant waveguide mode that interacts with a periodic nanostructure and hence outcouples via diffraction. We show that the enhancement of resonance emission can be controlled by tuning the design parameters. We also demonstrate that the enhanced emission is attributable to the accelerated spontaneous emission rate that increases the probability of photon emission in the resonant mode, accompanied by enhanced the local density of photonic states. This study demonstrates that nanostructured luminescent materials can be designed to exhibit functional and enhanced emission. We anticipate that our concept will be used to improve the performance of a variety of photonic and optical applications ranging from bio/chemical sensors to lighting, displays and projectors.

Human-induced marine ecological degradation: micropaleontological perspectives.

We analyzed published downcore microfossil records from 150 studies and reinterpreted them from an ecological degradation perspective to address the following critical but still imperfectly answered questions: (1) How is the timing of human-induced degradation of marine ecosystems different among regions? (2) What are the dominant causes of human-induced marine ecological degradation? (3) How can we better document natural variability and thereby avoid the problem of shifting baselines of comparison as degradation progresses over time? The results indicated that: (1) ecological degradation in marine systems began significantly earlier in Europe and North America (∼1800s) compared with Asia (post-1900) due to earlier industrialization in European and North American countries, (2) ecological degradation accelerated globally in the late 20th century due to post-World War II economic growth, (3) recovery from the degraded state in late 20th century following various restoration efforts and environmental regulations occurred only in limited localities. Although complex in detail, typical signs of ecological degradation were diversity decline, dramatic changes in total abundance, decrease in benthic and/or sensitive species, and increase in planktic, resistant, toxic, and/or introduced species. The predominant cause of degradation detected in these microfossil records was nutrient enrichment and the resulting symptoms of eutrophication, including hypoxia. Other causes also played considerable roles in some areas, including severe metal pollution around mining sites, water acidification by acidic wastewater, and salinity changes from construction of causeways, dikes, and channels, deforestation, and land clearance. Microfossils enable reconstruction of the ecological history of the past 10(2)-10(3) years or even more, and, in conjunction with statistical modeling approaches using independent proxy records of climate and human-induced environmental changes, future research will enable workers to better address Shifting Baseline Syndrome and separate anthropogenic impacts from background natural variability.

Selective fluorescence detection of 8-oxoguanosine with 8-oxoG-clamp.

8-oxoguanosine, which is derived from the oxidation of guanosine (dG), is known to induce transversion mutations (G:C-->T:A) in DNA. The compounds with a small molecular weight for recognizing 8-oxoG were designed on the basis of the structure of the G-clamp, which is reported to have selective affinity toward guanosine. The G-clamp derivatives with the additional binding units toward 8-oxoG were effectively synthesized and named "8-oxoG-clamps." The 8-oxoG-clamp completely discriminated 8-oxoG from other nucleosides by fluorescence quenching.

Development of a specific fluorescent probe for 8-oxoguanosine.

8-Oxoguanosine (8-oxoG) is derived from the oxidation of guanosine (dG) and is known to induce transversion mutations (G:C to T:A) in DNA. We have already reported the fluorescent probe "8-oxoG-clamp", which shows a selective fluorescence quenching phenomenon toward 8-oxoG. In this study, attachment of an additional fluorophore to 8-oxoG-clamp was investigated as a strategy for the detection of 8-oxoG by a fluorescence color change attributed to the 8-oxoG-clamp.

Fluorescence detection of 8-oxoguanosine by G-clamp derivatives.

8-Oxoguanosine, which is derived by the oxidation of guanosine (dG), is known to induce transversion mutations (G:C-->T:A) in DNA. The compounds with small molecular weight for recognizing 8-oxoG were designed on the basis of the structure of the G-clamp, which is reported to have selective affinity toward guanosine. The G-clamp derivatives with the additional binding units toward 8-oxoG were effectively synthesized and named "8-oxoG-clamps". Binding properties were measured by fluorescence quenching of 8-oxoG-clamps. Among the synthesized derivatives, 8-oxoG-clamp with N-benzyloxycarbonyl (Cbz) unit completely discriminated 8-oxoG from other nucleosides by fluorescence quenching.