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With the development of global industry, carbon dioxide emissions surged. The conversion of carbon dioxide from the air results in some CO 3 2- in seawater is an important indicator of the degree of ocean acidification. In this study, natural fluorescent protein phycocyanin (PC) was used as a fluorescent probe, and a fluorescence detection method was established for quantitative monitoring of CO 3 2- in seawater is an important indicator of the degree of ocean acidification. In this study, natural fluorescent protein phycocyanin (PC) was used as a fluorescent probe, and a fluorescence detection method was established for quantitative monitoring of CO 3 in tap water and seawater, acquiring satisfactory recovery between 99.28 % and 106.40 %. More importantly, paper-based test strips were easily fabricated using PC, enabling the rapid, visual, and on-site detection of CO 2- with quick response time (within 50 s), high sensitivity, and selectivity. The fluorescence quenching phenomenon between PC and CO 3 . By capturing fluorescent images and analyzing the corresponding RGB value via a smartphone, the linear calibration ranged from 0.5 μM to 500.0 μM with LOD of 0.11 μM was obtained. Satisfactory recoveries were acquired in tap water (98.00 %-107.50 %) and seawater (97.30 %-101.74 %), respectively. Therefore, integrating the PC fluorescent paper with a smartphone realizes the rapid, visual, and on-site detection of CO 2- was mainly attributed to static quenching. The limit of detection (LOD) was 0.42 μM and the method was successfully applied to monitor CO 3 2- in tap water and seawater, acquiring satisfactory recovery between 99.28 % and 106.40 %. More importantly, paper-based test strips were easily fabricated using PC, enabling the rapid, visual, and on-site detection of CO 3 2- with the aid of a smartphone. The visual detection integrated with the smartphone was converted to data information (RGB value) through a Color Picker APP and successfully used for quantitative identification of CO 3 2- . By capturing fluorescent images and analyzing the corresponding RGB value via a smartphone, the linear calibration ranged from 0.5 μM to 500.0 μM with LOD of 0.11 μM was obtained. Satisfactory recoveries were acquired in tap water (98.00 %-107.50 %) and seawater (97.30 %-101.74 %), respectively. Therefore, integrating the PC fluorescent paper with a smartphone realizes the rapid, visual, and on-site detection of CO 3 2- in the water environment, which is expected to broaden application prospects of monitoring ocean acidification degree., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

A disposable electrochemical lateral flow paper-based sensing device for heavy metal detection is proposed. The quantification of lead and cadmium in aqueous samples is demonstrated in a range from 10 to 100 ppb with a limit of detection of 7 and 11 ppb respectively. Moreover, the platform itself, which is made of paper, served as a sample pretreatment material due to its filtering properties. Real samples, especially in which the matrix is usually turbid and would in principle need a previous filtration, are successfully analyzed. This lab-on-paper device is simple, low cost, easy to fabricate, and portable, being a promising tool for new point-of-care applications in environmental monitoring, public health, and food safety.

The relevance of pH assessment in clinical analysis, environmental and industrial control, has raised the demand for the development of portable, low cost and easy-to-use monitoring systems. This paper proposes a pH sensor printed on a paper support passivated with a solid-ink coating. The sensor exploits the pH sensitivity of a reduced graphene oxide functionalized with 3-(4-aminophenil)propionic acid. The sensor responded in the pH range [4], [10] and had a sensitivity of 46 mV/pH. Tests on human plasma and seawater proved this pH sensor to have similar performances than those of a commercial pH-meter with an uncertainty of 0.1 and 0.2 pH unit in plasma and seawater, respectively.

A bilayer photothermal paper-based 3D cone flowing evaporator with high solar light absorption, low water evaporation enthalpy and excellent salt-rejecting performance is fabricated using multilayered MXene, ultralong hydroxyapatite nanowires, and hydrophilic polymers. The 3D cone flowing evaporator cooperates with a siphon effect-driven unidirectional fluid transportation unit to guide concentrated saline flows out from the evaporating surface, leading to high water evaporation rate and salt-rejecting stable seawater desalination performance. [Display omitted] • A bilayer photothermal paper-based cone flowing water evaporator is reported. • The evaporator exhibits excellent properties for solar seawater desalination. • The evaporator exhibits much higher water evaporation rate than most reported values. • The evaporator can effectively prevent salt accumulation on the evaporating surface. Solar energy-driven water evaporation technology is a promising, low-cost and sustainable approach to alleviate the global clean water shortage, but usually suffers from low water evaporation rate and severe salt deposition on the water evaporation surface. In this work, a hydrophilic bilayer photothermal paper-based three-dimensional (3D) cone flowing evaporator was designed and prepared for stable high-performance seawater desalination with excellent salt-rejecting ability. The as-prepared bilayer photothermal paper consisted of MXene (Ti 3 C 2 T x) and HAA (ultralong hydroxyapatite nanowires, poly(acrylic acid), and poly(acrylic acid-2-hydroxyethyl ester)). The accordion-like multilayered MXene acted as the efficient solar light absorber, and ultralong hydroxyapatite (HAP) nanowires served as the thermally insulating and supporting skeleton with a porous networked structure. A siphon effect-driven unidirectional fluid transportation unit in the 3D cone flowing evaporator could guide the concentrated saline flowing away from the evaporating surface to prevent salt deposition on the evaporation surface, avoiding severe deterioration of the performance in solar water evaporation. Furthermore, combining high solar light absorption and high photothermal conversion efficiencies, low water evaporation enthalpy (1838 ± 11 J g−1), and additional energy taken from the ambient environment, the as-prepared cone flowing evaporator exhibited a high water evaporation rate of 3.22 ± 0.20 kg m−2 h−1 for real seawater under one sun illumination (1 kW m−2), which was significantly higher than many values reported in the literature. This study provides an effective approach for designing high-performance solar energy-driven water evaporators for sustainable seawater desalination and wastewater purification. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mining seawater C a 2 + and M g 2 + for recovering F - was proposed. • This was achieved through the high affinity between carboxyl and C a 2 + / M g 2 + . • The C a F 2 / M g F 2 colloids were recovered and retained by the filter papers. • Additional flocculation was avoided. Resource reclamation with low carbon emissions is highly desirable from the perspective of the circular economy. We propose a green solution in this study, which involves mining calcium and magnesium from seawater as an effective reagent for the recovery of valuable fluoride. This was achieved by esterifying the cellulose filter papers with citric acid to associate carboxyl groups onto their surfaces. Consequently, the high affinity between the carboxyl group and alkaline earth elements enabled efficient and selective loading of C a 2 + (0.193 ± 0.001 mmol- C a 2 + /g) and M g 2 + (0.127 ± 0.001 mmol- M g 2 + /g) onto the filter papers, reaching up to 96% and 60% of the available active sites, respectively. When applied in natural seawater, the esterified filter papers successfully captured both C a 2 + (0.110 ± 0.007 mmol- C a 2 + /g) and M g 2 + (0.078 ± 0.005 mmol- M g 2 + /g) simultaneously. The presence of IR singlet symmetric (ν s COO, ≈ 1450 cm−1) stretching vibrations indicated that both C a 2 + and M g 2 + ions were complexed with carboxyl groups in a bridging unidentate mode. The adsorption capacity of C a 2 + and M g 2 + was likely influenced by the varying thickness of their hydration shells within the highly overlapped electric double layers presented in the micropores of the esterified filter papers. The papers loaded with C a 2 + and M g 2 + were subsequently utilized for fluoride recovery in simulated HF wastewater. The formation of C a F 2 / M g F 2 colloids effectively recovered the stoichiometric amount of fluoride (C a F 2.46 and M g F 1.72), which were retained on the surface of the filter papers. Additional flocculation for colloid separation is thus avoided, resulting in a significant increase in the content of reclaimed fluoride. Increasing the density of associated carboxyl groups is crucial for effectively complexing a greater amount of seawater C a 2 + / M g 2 + and, consequently, enhancing the capacity of fluoride reclamation by esterified filter papers. [ABSTRACT FROM AUTHOR]

Marine protists and their metabolic activities are intricately tied to the cycling of nutrients and the flow of energy through microbial food webs. Physiochemical changes in the environment, such as those that result from mesoscale eddies, may impact protistan communities, but the effects that such changes have on protists are poorly known. A metatranscriptomic study was conducted to investigate how eddies affected protists at adjacent cyclonic and anticyclonic eddy sites in the oligotrophic ocean at four depths from 25 to 250 m. Eddy polarity impacted protists at all depths sampled, although the effects of eddy polarity were secondary to the impact of depth across the depth range. Eddy-induced vertical shifts in the water column yielded differences in the cyclonic and anticyclonic eddy protistan communities, and these differences were the most pronounced at and just below the deep chlorophyll maximum. An analysis of transcripts associated with protistan nutritional physiology at 150 m revealed that cyclonic eddies may support a more heterotrophic community, while anticyclonic eddies promote a more phototrophic community. The results of this study indicate that eddies alter the metabolism of protists particularly in the lower euphotic zone and may therefore impact carbon export from the euphotic zone., (Environmental Microbiology© 2024 The Authors. Environmental Microbiology published by Applied Microbiology International and John Wiley & Sons Ltd.)

Gelatinous zooplankton are increasingly recognized to play a key role in the ocean's biological carbon pump. Appendicularians, a class of pelagic tunicates, are among the most abundant gelatinous plankton in the ocean, but it is an open question how their contribution to carbon export might change in the future. Here, we conducted an experiment with large volume in situ mesocosms (~55-60 m 3 and 21 m depth) to investigate how ocean acidification (OA) extreme events affect food web structure and carbon export in a natural plankton community, particularly focusing on the keystone species Oikopleura dioica, a globally abundant appendicularian. We found a profound influence of O. dioica on vertical carbon fluxes, particularly during a short but intense bloom period in the high CO 2 treatment, during which carbon export was 42%-64% higher than under ambient conditions. This elevated flux was mostly driven by an almost twofold increase in O. dioica biomass under high CO 2 . This rapid population increase was linked to enhanced fecundity (+20%) that likely resulted from physiological benefits of low pH conditions. The resulting competitive advantage of O. dioica resulted in enhanced grazing on phytoplankton and transfer of this consumed biomass into sinking particles. Using a simple carbon flux model for O. dioica, we estimate that high CO 2 doubled the carbon flux of discarded mucous houses and fecal pellets, accounting for up to 39% of total carbon export from the ecosystem during the bloom. Considering the wide geographic distribution of O. dioica, our findings suggest that appendicularians may become an increasingly important vector of carbon export with ongoing OA., (© 2023 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Cobalamin influences marine microbial communities because an exogenous source is required by most eukaryotic phytoplankton, and demand can exceed supply. Pseudocobalamin is a cobalamin analogue produced and used by most cyanobacteria but is not directly available to eukaryotic phytoplankton. Some microbes can remodel pseudocobalamin into cobalamin, but a scarcity of pseudocobalamin measurements impedes our ability to evaluate its importance for marine cobalamin production. Here, we perform simultaneous measurements of pseudocobalamin and methionine synthase (MetH), the key protein that uses it as a co-factor, in Synechococcus cultures and communities. In Synechococcus sp. WH8102, pseudocobalamin quota decreases in low temperature (17°C) and low nitrogen to phosphorus ratio, while MetH did not. Pseudocobalamin and MetH quotas were influenced by culture methods and growth phase. Despite the variability present in cultures, we found a comparably consistent quota of 300 ± 100 pseudocobalamin molecules per cyanobacterial cell in the Northwest Atlantic Ocean, suggesting that cyanobacterial cell counts may be sufficient to estimate pseudocobalamin inventories in this region. This work offers insights into cellular pseudocobalamin metabolism, environmental and physiological conditions that may influence it, and provides environmental measurements to further our understanding of when and how pseudocobalamin can influence marine microbial communities., (© 2024 The Author(s). Environmental Microbiology published by John Wiley & Sons Ltd.)

Global change stressors can modify ecological niches of species, thereby altering ecological interactions within communities and food webs. Yet, some species might take advantage of a fast-changing environment, allowing species with high niche plasticity to thrive under climate change. We used natural CO 2 vents to test the effects of ocean acidification on niche modifications of a temperate rocky reef fish assemblage. We quantified three ecological niche traits (overlap, shift and breadth) across three key niche dimensions (trophic, habitat and behavioural). Only one species increased its niche width along multiple niche dimensions (trophic and behavioural), shifted its niche in the remaining (habitat) was the only species to experience a highly increased density (i.e. doubling) at vents. The other three species that showed slightly increased or declining densities at vents only displayed a niche width increase in one (habitat niche) out of seven niche metrics considered. This niche modification was likely in response to habitat simplification (transition to a system dominated by turf algae) under ocean acidification. We further showed that, at the vents, the less abundant fishes had a negligible competitive impact on the most abundant and common species. This species appeared to expand its niche space, overlapping with other species, which likely led to lower abundances of the latter under elevated CO 2 . We conclude that niche plasticity across multiple dimensions could be a potential adaptation in fishes to benefit from a changing environment in a high-CO 2 world., (© 2024 The Author(s). Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.)

Purpose: The objective was to assess the efficacy of seawater nasal wash on symptom duration, intranasal viral load, household transmission in COVID-19 and URTIs., Methods: This prospective, randomized, controlled, multicentric, parallel study included 355 mild/moderate COVID-19 and URTI adults with rhinologic symptoms ≤ 48h. Active group performed 4-daily nasal washes with undiluted isotonic seawater versus control group (without nasal wash). Symptoms were self-assessed daily using the WURSS-21 questionnaire for 3 weeks. Viral load was measured by RT-PCR on nasopharyngeal swabs collected on Day 0, Day 5, Day 14 and Day 21. Digital droplet PCR was additionally performed for SARS-CoV-2., Results: Overall COVID-19 subjects recovered earlier the ability to accomplish daily activities in the active group (- 1.6 day, p = 0.0487) with earlier improvement of taste (- 2 days, p = 0.0404). COVID-19 subjects with severe nasal symptoms at D0 showed the earliest resolution of anosmia (- 5.2 days, p = 0.0281), post-nasal drip (- 4.1 days, p = 0.0102), face pain/heaviness (- 4.5 days, p = 0.0078), headache (- 3.1 days, p = 0.0195), sore throat (- 3.3 days, p = 0.0319), dyspnea (- 3.1 days, p = 0.0195), chest congestion (- 2.8 days, p = 0.0386) and loss of appetite (- 4.5 days, p = 0.0186) with nasal wash. In URTIs subjects, an earlier resolution of rhinorrhea (- 3.5 days, p = 0.0370), post-nasal drip (- 3.7 days, p = 0.0378), and overall sickness (- 4.3 days, p = 0.0248) was reported with nasal wash. Evolution towards more severe COVID-19 was lower in active vs control, with earlier viral load reduction in youngest subjects (≥ 1.5log10 copies/10000 cells at Day 5: 88.9% vs 62.5%, p = 0.0456). In the active group, a lower percentage of SARS-CoV-2 positive household contacts (0-10.7%) was reported vs controls (3.2-16.1%) among subjects with Delta variant (p = 0.0413)., Conclusion: This trial showed the efficacy and safety of seawater nasal wash in COVID-19 and URTIs., Trial Registration: Trial registry ClinicalTrials.gov: NCT04916639. Registration date: 04.06.2021., (© 2024. The Author(s).)

Previous studies on high concentrations of polycyclic aromatic hydrocarbon (PAHs) present in the shallow-marine Um-Sohryngkew River (USR) Cretaceous/Paleogene Boundary (KPB) section suggested regional fire incidences and biotic stress on life. However, such observations at the USR site have not been confirmed so far anywhere else in the region, we, therefore, do not know whether the signal was local or regional. Thus, to find out charred organic markers associated with the shelf facies KPB outcrop (at a distance of over 5 km) of the Mahadeo-Cherrapunji road (MCR) section, PAHs were analyzed using gas chromatography-mass spectroscopy. Data show a notable rise in the PAHs and exhibit maximum abundance in the shaly KPB transition layer (in biozone P0) and the immediately underlying layer. The PAH excursions match well with the major incidences of the Deccan volcanic episodes and convergence of the Indian plate with the Eurasian and Burmese plates. These events were responsible for seawater disturbances and eustatic and depositional changes, including the retreat of the Tethys. The incidence of high amount of pyogenic PAHs unrelated to the total organic carbon content is suggestive of wind-blown or aquatic system transportation. A down-thrown shallow-marine facies of the Therriaghat block was responsible for an early accumulation of PAHs. However, the spike of perylene in the immediately underlying KPB transition layer is plausibly linked to the Chicxulub impact crater core. Anomalous concentrations of combustion-derived PAHs together with the high fragmentation and dissolution of the planktonic foraminifer shells show marine biodiversity and biotic distress. Significantly, the pyrogenic PAH excursions are restricted to either the KPB layer itself or strictly below or above it, indicating regional fire incidences and attendant KPB transition (66.016 ± 0.050 Ma)., (© 2023 John Wiley & Sons Ltd.)

Solar desalination devices utilizing sustainable solar energy and the abundant resource of seawater has great potential as a response to global freshwater scarcity. Herein, a bilayered solar evaporator was designed and fabricated utilizing a facile paper sheet forming technology, which was composed of cellulose fibers decorated with Fe3O4 nanoparticles as the top absorbent layer and the original cellulose fibers as the bottom supporting substrate. The characterization of the cellulose fibers decorated with Fe3O4 nanoparticles revealed that the in situ formed Fe3O4 nanoparticles were successfully loaded on the fiber surface and presented a unique rough surface, endowing the absorber layer with highly efficient light absorption and photothermal conversion. Moreover, due to its superhydrophilic property, the cellulose fiber-based bottom substrate conferred ultra-speed water transport capability, which could enable an adequate water supply to combat the water loss caused by continuous evaporation on the top layer. With the advantages mentioned above, our designed bilayered paper-based evaporator achieved an evaporation rate ~1.22 kg m−2 h−1 within 10 min under 1 sun irradiation, which was much higher than that of original cellulose cardboard. Based on the simple and scalable manufacture process, the bilayered paper-based evaporator may have great potential as a highly efficient photothermal conversion material for real-world desalination applications. [ABSTRACT FROM AUTHOR]

Challengerids, phaeogromids rhizarian protists, are emblematic protists of the deep sea but are also enigmatic as they occur in very low concentrations. In previous studies, we reported on temporal changes in abundance at a near-shore mesopelagic site, but only as part of sampling of the entire microplankton assemblage, not well-suited for examining phaeogromids. Consequently, we turned to using a closing plankton net to provide material from large volumes of seawater, thus allowing for more robust estimates of concentrations and material for observations of living cells, to our knowledge the first made. Here, we report our results on the four most commonly occurring species: Challengeranium diadon, Challengereron willemoesii, Challengeria xiphodon, and Euphysetta lucani. In contrast to our previous report, we found that changes in concentrations were not related to water column stratification, and the four species roughly co-varied with time. Observations of live cells revealed that all four species deploy tentacle-like pseudopods and also very large unstructured webs of fine pseudopods. The similarities in feeding webs suggest similar prey are exploited, and the similar temporal changes in abundances suggest a common factor or factors (unknown at this time) govern their concentrations. Films of live cells are provided in Supplementary Files., (© 2023 International Society of Protistologists.)

Molecularly imprinted polymer (MIP-QDs) with fluorescence quenching ability toward propazine was synthesized for propazine detection. b(Blue)-MIP-QDs were prepared using ZnCdS/ZnS QDs via reverse micro-emulsion, whereas r(red)-MIP-QDs were synthesized using CdSe/ZnS QDs. By utilizing graphene quantum dots (GQDs) as a stable fluorescence intensity reference, the wide-gamut fluorescence test paper was constructed on the basis of mixing b-MIP-QDs, r-MIP-QDs, and GQDs under the optimal ratio. When analyzing spiked propazine in fish and seawater samples using a test paper, satisfactory recoveries of 104.0 %–114.6 % and 92.0 %–96.4 % were obtained, with corresponding limits of detection of 5.0 μg/kg and 1.0 μg/L, respectively. The RGB extractor was utilized to extract the actual fluorescence color and construct a dataset consisting of R, G, and B values, as well as concentration data from 400 samples. The SVR model of Python 3.9.7 was used to obtain and analyze the concentration and feature data. After optimization, the constructed model achieved a correlation coefficient of 0.98 and an RMSE of only 1.81, indicating high prediction accuracy and excellent generalization ability that meet quenching prediction requirements. As an intelligent and rapid detection method, this model holds significant practical significance. [Display omitted] • A wide-gamut fluorescence visual test paper was fabricated. • The visual test paper demonstrates excellent linearity, accuracy, precision, and sensitivity for promazine detect. • An RGB model by support vector machine were constructed. • The model exhibits high accuracy and strong generalization ability. [ABSTRACT FROM AUTHOR]

Most Neoproterozoic iron formations (NIF) are closely associated with global or near-global "Snowball Earth" glaciations. Increasingly, however, studies indicate that some NIFs show no robust evidence of glacial association. Many aspects of non-glacial NIF genesis, including the paleo-environmental setting, Fe(II) source, and oxidation mechanisms, are poorly understood. Here, we present a detailed case study of the Jiapigou NIF, a major non-glacial NIF within a Neoproterozoic volcano-sedimentary sequence in North Qilian, northwestern China. New U-Pb geochronological data place the depositional age of the Jiapigou NIF at ~600 Ma. Petrographic and geochemical evidence supports its identification as a primary chemical sediment with significant detrital input. Major and trace element concentrations, REE + Y systematics, and ε Nd (t) values indicate that iron was sourced from mixed seawater and hydrothermal fluids. Iron isotopic values (δ 56 Fe = -0.04‰-1.43‰) are indicative of partial oxidation of an Fe(II) reservoir. We infer that the Jiapigou NIF was deposited in a redox stratified water column, where hydrothermally sourced Fe(II)-rich fluids underwent oxidation under suboxic conditions. Lastly, the Jiapigou NIF has strong phosphorous enrichments, which in other iron formations are typically interpreted as signals for high marine phosphate concentrations. This suggests that oceanic phosphorus concentrations could have been enriched throughout the Neoproterozoic, as opposed to simply during glacial intervals., (© 2022 John Wiley & Sons Ltd.)

One method to assess environmental effects from industrial emissions to coastal and inland waters, e.g. from pulp and paper industries, is to quantify these emissions with mass balance models. In this study six different mass balance models for phosphorus with varying degrees of complexity have been tested in 11 Swedish coastal areas. The majority of these areas are recipients of pulp and paper industries. The accuracy of model predictions of phosphorus and chlorophyll is evaluated and compared between models. The results imply that for the included water bodies, models containing state variables for phosphorus in surface water and deep water are superior to models treating the water column as a completely mixed entity. The results do not justify the separation of phosphorus into dissolved and particulate fractions, but for chlorophyll predictions the results were significantly improved when phytoplankton was included as a state variable. Unless detailed descriptions or predictions of chlorophyll dynamics are required, modelling eutrophication in coastal areas may be considered as a matter of total phosphorus in two water compartments plus sediments.

Green and clean energy technologies, including fuel cells, metal-air batteries, water splitting et al., are becoming more significant for our lives. Oxygen reduction reaction (ORR), hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are key reaction processes for fuel cells, metal-air batteries and water splitting. Therefore, it is highly desirable to design a multifunctional catalyst, which owns catalytic performance under a widely applied range. Herein, we demonstrate a novel multifunctional catalyst (Co/Co 3 O 4 @C) by carbonizing a composite material constructed of zeolite imidazolate framework and carbon fiber paper (ZIF-L-Co@CP). It is a carbon-based material containing metallic Co and Co 3 O 4 as a low-cost and effective catalyst toward the ORR and overall water splitting. For ORR, the Co/Co 3 O 4 @C catalyst shows high half-wave potential in both alkaline and acidic media, 0.823 V for 0.1 M KOH and 0.672 V for 0.1 M HClO 4. More importantly, it exhibits good catalytic activities of hydrogen and oxygen evolutions to perform overall splitting in actual seawater. The Co/Co 3 O 4 @C catalyst was prepared by using a composite of ZIF-L-Co nanosheets grown on CP as the precursor, which not only shows excellent activity for ORR in both alkaline and acidic solutions, but also has good ability for overall actual seawater splitting. Image 1 • E 1/2 (0.823 V) of Co/Co 3 O 4 @C catalyst is close to Pt/C in 0.1 M KOH for ORR. • Co/Co 3 O 4 @C catalyst shows excellent ORR performance in 0.1 M KOH and 0.1 M HClO 4. • Co/Co 3 O 4 @C is a good catalyst for overall water splitting in actual seawater. [ABSTRACT FROM AUTHOR]

We investigated the impact of pressure on thermophilic, chemolithoautotrophic NO 3 - reducing bacteria of the phyla Campylobacterota and Aquificota isolated from deep-sea hydrothermal vents. Batch incubations at 5 and 20 MPa resulted in decreased NO 3 - consumption, lower cell concentrations, and overall slower growth in Caminibacter mediatlanticus (Campylobacterota) and Thermovibrio ammonificans (Aquificota), relative to batch incubations near standard pressure (0.2 MPa) conditions. Nitrogen isotope fractionation effects from chemolithoautotrophic NO 3 - reduction by both microorganisms were, on the contrary, maintained under all pressure conditions. Comparable chemolithoautotrophic NO 3 - reducing activities between previously reported natural hydrothermal vent fluid microbial communities dominated by Campylobacterota at 25 MPa and Campylobacterota laboratory isolates at 0.2 MPa, suggest robust similarities in cell-specific NO 3 - reduction rates and doubling times between microbial populations and communities growing maximally under similar temperature conditions. Physiological and metabolic comparisons of our results with other studies of pressure effects on anaerobic chemolithoautotrophic processes (i.e., microbial S 0 -oxidation coupled to Fe(III) reduction and hydrogenotrophic methanogenesis) suggest that anaerobic chemolithoautotrophs relying on oxidation-reduction (redox) reactions that yield higher Gibbs energies experience larger shifts in cell-specific respiration rates and doubling times at increased pressures. Overall, our results advance understanding of the role of pressure, its relationship with temperature and redox conditions, and their effects on seafloor chemolithoautotrophic NO 3 - reduction and other anaerobic chemolithoautotrophic processes., (© 2022 John Wiley & Sons Ltd.)

This work describes the development of a microfluidic paper-based analytical device (μPAD) for the determination of copper in fresh and marine waters. A functionalized rhodamine-based chelator was synthesized and used as a chromogenic reagent, forming a highly intense pink complex with the analyte. The aim was to create a paper device that offers optimal performance and provides in-situ , rapid and cost-effective analysis in line with World Health Organization guidelines. The influence on the determination of several physical and chemical parameters was evaluated aiming to achieve the best performance. Under optimised conditions, a linear correlation was established in the range of 0.05–0.50 mg L−1 of copper, with a limit of detection of 10 μg L−1. The accuracy of the proposed method was assessed by comparing the results obtained with the developed μPAD and the results obtained with Inductively Coupled Plasma measurements (RE < 10 %). Recovery studies were also performed using different types of water samples with no need for any prior sample pre-treatment: tap, well, river and seawater. The average recovery percentage of 101 % (RSD = 4.3 %) was obtained, a clear indication of no multiplicative matrix interferences. [Display omitted] • Copper determination in waters using a handheld-size microfluidic paper-based device incorporating a synthesized chelator. • Quantification of copper validated by comparison with Inductively Coupled Plasma – Optical Emission Spectrometer (ICP-OES). • Environmentally friendly assembly as there is no need for a wax printer. [ABSTRACT FROM AUTHOR]

Although coastal eutrophication is generally recognised as a recent phenomenon related to the well-documented increase in riverine nutrient delivery during the last 30 or 40 years, a few historical records paradoxically show that, in some places like the Southern Bight of the North Sea, or the Northern Adriatic, algal proliferation as intense as presently observed was already regularly occurring at the end of the 19th century. Estimated riverine nutrient loads from diffuse sources or from domestic point sources of waste water at that time are too low to account for these observations. We attempted a retrospective evaluation of the possible contribution of industrial activity to nutrient river loading. The figures indicate that, by the end of the last century, large scale use of traditional processes in textile and paper industries, in tanneries, candles factories and others was responsible for a dominant part of the nutrient load carried by rivers in Western Europe and could have caused nutrient inputs to coastal zones similar to the present ones.

Abstract: Huge numbers of cultural objects were damaged by microorganisms after having been soaked with seawater from the tsunami that followed the Great East Japan Earthquake on March 11, 2011. Among the cultural objects that were damaged, paper-based objects in the tsunami area were severely affected. In the present study, a culture-based analysis and on-site investigations were carried out to determine the extent of the microbial deterioration of paper-based objects (i.e., administrative documents and historical documents). Dark-colored fungi were isolated from black-spotted paper as Stachybotrys chartarum, which was observed to grow significantly in mineral salt medium supplemented with cellulose as the sole nutrient source; growth was shown in 10% NaCl. Two isolates from light red-spotted paper were related to Streptomyces sp. and Myxotrichum sp., respectively. These isolates generated red pigments in the mycelia and on the culture plates. Penicillium-related isolates were dominant in the sample tested, and they showed a higher level of NaCl tolerance. From the results of our on-site investigations, a unique discoloration, mainly black- and light red-spotted alterations caused by microbes, was observed on many paper-based objects that had been left wet for several months. The adhesive tape method applied to the black-spotted and red-spotted areas on damaged documents, Stachybotrys, Chaetomium and Cladosporium, and Actinomycetales bacterium were observed, respectively. With regard to the discoloration found on tsunami-affected paper-based objects, Stachybotrys and Streptomyces sp. seem to be responsible for the black- and red-spotted paper alterations, respectively. [Copyright &y& Elsevier]

Heterotrophic bacteria hydrolyze high molecular weight (HMW) organic matter extracellularly prior to uptake, resulting in diffusive loss of hydrolysis products. An alternative 'selfish' uptake mechanism that minimises this loss has recently been found to be common in the ocean. We investigated how HMW organic matter addition affects these two processing mechanisms in surface and bottom waters at three stations in the North Atlantic Ocean. A pulse of HMW organic matter increased cell numbers, as well as the rate and spectrum of extracellular enzymatic activities at both depths. The effects on selfish uptake were more differentiated: in Gulf Stream surface waters and productive surface waters south of Newfoundland, selfish uptake of structurally simple polysaccharides increased upon HMW organic matter addition. The number of selfish bacteria taking up structurally complex polysaccharides, however, was largely unchanged. In contrast, in the oligotrophic North Atlantic gyre, despite high external hydrolysis rates, the number of selfish bacteria was unchanged, irrespective of polysaccharide structure. In deep bottom waters (> 4000 m), structurally complex substrates were processed only by selfish bacteria. Mechanisms of substrate processing-and the extent to which hydrolysis products are released to the external environment-depend on substrate structural complexity and the resident bacterial community., (© 2024 Applied Microbiology International and John Wiley & Sons Ltd.)

Microbial pollution of recreational waters leads to millions of skin, respiratory, and gastrointestinal illnesses globally. Fecal indicator bacteria (FIB) are monitored to assess recreational waters but may not reflect the presence of Staphylococcus aureus, a global leader in bacterial fatalities. Since many community-acquired S. aureus skin infections are associated with high recreational water usage, this study measured and modeled S. aureus, methicillin-resistant S. aureus (MRSA), and FIB (Enterococcus spp., Clostridium perfringens) concentrations in seawater and sand at six beaches in Hilo, Hawai'i, USA, over 37 sample dates from July 2016 to February 2019 using culturing techniques. Generalized linear models predicted bacterial concentrations with physicochemical and environmental data. Beach visitors were also surveyed on their preferred activities. S. aureus and FIB concentrations were roughly 6-78 times higher at beaches with freshwater discharge than at those without. Seawater concentrations of Enterococcus spp. were positively associated with MRSA but not S. aureus. Elevated S. aureus was associated with lower tidal heights, higher freshwater discharge, onsite sewage disposal system density, and turbidity. Regular monitoring of beaches with freshwater input, utilizing real-time water quality measurements with robust modeling techniques, and raising awareness among recreational water users may mitigate exposure to S. aureus, MRSA, and FIB. PRACTITIONER POINTS: Staphylococcus aureus and fecal bacteria concentrations were higher in seawater and sand at beaches with freshwater discharge. In seawater, Enterococcus spp. positively correlated with MRSA, but not S. aureus. Freshwater discharge, OSDS density, water turbidity, and tides significantly predicted bacterial concentrations in seawater and sand. Predictive bacterial models based upon physicochemical and environmental data developed in this study are readily available for user-friendly application., (© 2024 Water Environment Federation.)

This review describes the research that has been carried out into estrogenic effects occurring in aquatic environments, both freshwater and marine, and the substances found to be responsible. In summary, estrogenic (and probably some anti-androgenic) activity has mainly been detected in a variety of treated sewage and other effluents, but also as a result of certain chemical spills and deliberate applications. This activity has resulted in a number of effects in vertebrate wildlife that can best be described as feminization, although the severity of these effects ranges from biomarkers of exposure such as vitellogenin induction in males through to morphological changes in sex organs and complete sex reversal. The implications of these changes for the future of aquatic wildlife populations have not yet been thoroughly explored. It is unlikely that all the causative substances have yet been discovered, but those which have been positively identified include natural and synthetic estrogenic hormones, natural plant sterols, synthetic alkylphenols, and certain organochlorine substances. The review concludes that there is now a need to investigate the consequences for wildlife populations of exposure to these materials, by means of a variety of field experiments and investigations.

Ocean deoxygenation is one of the major consequences of climate change. In coastal waters, this process can be exacerbated by eutrophication, which is contributing to an alarming increase in the so-called 'dead zones' globally. Despite its severity, the effect of reduced dissolved oxygen has only been studied for a very limited number of organisms, compared to other climate change impacts such as ocean acidification and warming. Here, we experimentally assessed the response of sponges to moderate and severe simulated hypoxic events. We ran three laboratory experiments on four species from two different temperate oceans (NE Atlantic and SW Pacific). Sponges were exposed to a total of five hypoxic treatments, with increasing severity (3.3, 1.6, 0.5, 0.4 and 0.13 mg O 2  L -1 , over 7-12-days). We found that sponges are generally very tolerant of hypoxia. All the sponges survived in the experimental conditions, except Polymastia crocea, which showed significant mortality at the lowest oxygen concentration (0.13 mg O 2  L -1 , lethal median time: 286 h). In all species except Suberites carnosus, hypoxic conditions do not significantly affect respiration rate down to 0.4 mg O 2  L -1 , showing that sponges can uptake oxygen at very low concentrations in the surrounding environment. Importantly, sponges displayed species-specific phenotypic modifications in response to the hypoxic treatments, including physiological, morphological and behavioural changes. This phenotypic plasticity likely represents an adaptive strategy to live in reduced or low oxygen water. Our results also show that a single sponge species (i.e., Suberites australiensis) can display different strategies at different oxygen concentrations. Compared to other sessile organisms, sponges generally showed higher tolerance to hypoxia, suggesting that sponges could be favoured and survive in future deoxygenated oceans., (© 2021 John Wiley & Sons Ltd.)

A bio-inspired cellulose paper–poly(amidoxime) composite hydrogel is explored via UV-polymerization. This hydrogel has a highly efficient uranium capture capacity of up to 6.21 mg g−1 for WU/Wdry gel and 12.9 mg g−1 for WU/Wpoly(amidoxime) in seawater for 6 weeks, due to its enhanced hydrophilicity, good hydraulic/ionic conductivity and broad-spectrum antibacterial performance. [ABSTRACT FROM AUTHOR]