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Our knowledge on biogeochemistry and microbial ecology of marine blue holes is limited due to challenges in collecting multilayered water column and oxycline zones. In this study, we collected samples from 16 water layers in Yongle blue hole (YBH) located in the South China Sea using the in situ microbial filtration and fixation (ISMIFF) apparatus. The microbial communities based on 16S rRNA metagenomic reads for the ISMIFF samples showed high microbial diversity and consistency among samples with similar dissolved oxygen levels. At the same depth of the anoxic layer, the ISMIFF samples were dominated by sulfate-reducing bacteria from Desulfatiglandales (17.96%). The sulfide concentration is the most significant factor that drives the division of microbial communities in YBH, which might support the prevalence of sulfate-reducing microorganisms in the anoxic layers. Our results are different from the microbial community structures of a Niskin sample of this study and the reported samples collected in 2017, in which a high relative abundance of Alteromonadales (26.59%) and Thiomicrospirales (38.13%), and Arcobacteraceae (11.74%) was identified. We therefore demonstrate a new profile of microbial communities in YBH probably due to the effect of sampling and molecular biological methods, which provides new possibilities for further understanding of the material circulation mechanism of blue holes and expanding anoxic marine water zones under global warming. [ABSTRACT FROM AUTHOR]

During the COVID-19 pandemic, wastewater-based epidemiology (WBE) has proven to be an effective tool for monitoring the prevalence of SARS-CoV-2 in urban communities. However, low-cost, simple, and reliable wastewater sampling techniques are still needed to promote the widespread adoption of WBE in many countries. Since their first use for public health surveillance in the 1950s, many types of passive samplers have been proposed, however, there have been few systematic studies comparing their ability to co-capture enveloped viruses and bacteria. Here, we evaluated the laboratory and field performance of 8 passive sampler materials (NanoCeram, ZetaPlus, nylon and ion exchange membranes, cellulose acetate filters, glass wool, cotton-based Moore swabs and tampons) to capture viruses and bacteria from wastewater. Viral capture focused on SARS-CoV-2, the bacteriophage Phi6 and the faecal marker virus, crAssphage. We showed that the best performing passive sampler in terms of cost, ease of deployment and viral capture were the electronegative cotton-based swabs and tampons. We speculate that viral capture is a combination of trapping of particulate matter to which viruses are attached, as well as electrostatic attraction of viral particles from solution. When deployed at wastewater treatment plants, the passive samplers worked best up to 6 h, after which they became saturated or exhibited a loss of virus, probably due to night-time wash-out. The patterns of viral capture across the different sampling materials were similar providing evidence that they can be used to monitor multiple public health targets. The types of bacteria trapped by the passive samplers were material-specific, but possessed a different 16S rRNA gene profile to the wastewater, suggesting preferential retention of specific bacteria. We conclude that the choice of passive sampler and deployment time greatly influences the pattern and amount of viral and bacterial capture. [ABSTRACT FROM AUTHOR]

Discrete water samples represent a snapshot of conditions at a particular moment in time and may not represent a true chemical exposure caused by changes in chemical input, tide, flow, and precipitation. Sampling technologies have been engineered to better estimate time-weighted concentrations. In this study, we consider the utility of three integrative sampling platforms: polar organic chemical integrative sampler (POCIS), silicone bands (SBs), and continuous, low-level aquatic monitoring (CLAM). This experiment used simulated southeastern salt marsh mesocosm systems to evaluate the response of passive (POCIS, SBs) and active sampling (CLAM) devices along with discrete sampling methodologies. Three systems were assigned to each passive sampler technology. Initially, all tanks were dosed at nominal (low) bifenthrin, pyrene, and triclosan concentrations of 0.02, 2.2, and 100 µg/L, respectively. After 28 days, the same treatment systems were dosed a second time (high) with bifenthrin, pyrene, and triclosan at 0.08, 8.8, and 200 µg/L, respectively. For passive samplers, estimated water concentrations were calculated using published or laboratory-derived sampling rate constants. Chemical residues measured from SBs resulted in high/low ratios of approximately 2x, approximately 3x, and 1x for bifenthrin, pyrene, and triclosan. A similar pattern was calculated using data from POCIS samples (~4x, ~3x, ~1x). Results from this study will help users of CLAM, POCIS, and SB data to better evaluate water concentrations from sampling events that are integrated across time. Integr Environ Assess Manag 2024;20:1384-1395. © 2024 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC)., (© 2024 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).)

Ceres is a large water-rich dwarf planet located within the asteroid belt. Its surface displays evidence of material sourced from a deep subsurface liquid brine layer within recent geologic time, making it a candidate ocean world with possible present-day activity. However, Ceres lacks a substantial atmosphere and likely does not possess a global magnetic field. Therefore, any material emplaced or exposed on the surface will be subject to weathering by charged particles of solar and galactic origin. We have evaluated the effect of charged particle radiation on material within the near-surface of Ceres and find that the timescale for radiation-induced modification and destruction of organics and endogenic material is ∼100 Myr to 1 Gyr within the top 10–20 cm of the surface. Furthermore, we find that the timescale for sterilization of any putative living organisms contained within material at these depths is <500 kyr. Future missions to the surface may therefore consider targeting regions with geologic ages that fall between these two timescales to avoid the risk of backward contamination while ensuring that sampled material is not heavily radiation processed. [ABSTRACT FROM AUTHOR]

In order to understand deposit formation during urea selective catalytic reduction (SCR) resulting from isocyanic acid (HNCO) formation, the present study investigates the potential of HNCO hydrolysis by spatially resolved gas phase concentration profiles along a single catalyst channel of commercial Cu‐zeolite and V‐based SCR catalysts. The spatially resolved profiles, obtained in a special hot gas test rig via capillary technique, provide information on reaction rates of HNCO hydrolysis, NH3 adsorption and NO conversion, hereby revealing a better performance of the standard V‐based catalyst regarding the HNCO hydrolysis, which is attributed to the TiO2 support. [ABSTRACT FROM AUTHOR]

In Pinhal Novo, Palmela, and neighboring municipalities, southern Lisbon region, there are a great number of small adobe masonry dwellings, made in the first half of the twentieth century. The vernacular dwellings were constructed by families that came from the north/center region of Portugal to work at the local manors and were called Caramel´s. Adobe samples from three of these dwellings were collected in Pinhal Novo and Moita, and tested for particle size distribution, X-ray diffraction, color, bulk density, ultrasonic pulse velocity, thermal conductivity, dry abrasion, flexural and compressive strength, capillary absorption and drying. It was possible to conclude that the adobe was not chemically stabilized and had no vegetable fibers. Average values for the adobe properties were defined and results were analyzed, revealing comparable to unstabilised adobe and even to lime stabilized adobe from other regions. The data on Caramel´s adobe can support the design of interventions to preserve at least some of these Caramel´s vernacular dwellings. [ABSTRACT FROM AUTHOR]

During the COVID-19 pandemic, wastewater-based epidemiology (WBE) has proven to be an effective tool for monitoring the prevalence of SARS-CoV-2 in urban communities. However, low-cost, simple, and reliable wastewater sampling techniques are still needed to promote the widespread adoption of WBE in many countries. Since their first use for public health surveillance in the 1950s, many types of passive samplers have been proposed, however, there have been few systematic studies comparing their ability to co-capture enveloped viruses and bacteria. Here, we evaluated the laboratory and field performance of 8 passive sampler materials (NanoCeram, ZetaPlus, nylon and ion exchange membranes, cellulose acetate filters, glass wool, cotton-based Moore swabs and tampons) to capture viruses and bacteria from wastewater. Viral capture focused on SARS-CoV-2, the bacteriophage Phi6 and the faecal marker virus, crAssphage. We showed that the best performing passive sampler in terms of cost, ease of deployment and viral capture were the electronegative cotton-based swabs and tampons. We speculate that viral capture is a combination of trapping of particulate matter to which viruses are attached, as well as electrostatic attraction of viral particles from solution. When deployed at wastewater treatment plants, the passive samplers worked best up to 6 h, after which they became saturated or exhibited a loss of virus, probably due to night-time wash-out. The patterns of viral capture across the different sampling materials were similar providing evidence that they can be used to monitor multiple public health targets. The types of bacteria trapped by the passive samplers were material-specific, but possessed a different 16S rRNA gene profile to the wastewater, suggesting preferential retention of specific bacteria. We conclude that the choice of passive sampler and deployment time greatly influences the pattern and amount of viral and bacterial capture.

The biogeochemistry of multi-elements, such as sulfur (S), phosphorus (P) and arsenic (As), is interlinked especially at interfaces of soil/sediment–water and plant rhizosphere. To explore the biogeochemical behavior of multi-elements such as S-P-As at interfaces, an in situ and high-resolution technology is required. In this study, we developed an in situ probe (LDHs-DGT) based on the diffusive gradients in thin-films technique using a single binding layer to realize the co-measurement of multi-elements including sulfide and oxyanions. Mg-Al layered double hydroxides (LDHs) were synthesized and incorporated into the probe’s binding layer. Laboratorial characterization showed that the LDHs-DGT probe had a high capacity for sulfide, phosphate and arsenate and can effectively determine their levels across a wide range of solution conditions, i.e., pH from 5 to 8 and ionic strengths from 0.005–0.01 mol L−1 NaNO3. The application potential of the LDHS-DGT probe in capturing the concentration profiles of sulfide and oxyanions across the soil/sediment–water interface at a centimeter scale was demonstrated. The synchronous co-variations of labile sulfide and phosphate were observed along an intact river sediment core, demonstrating the redox driven behaviors of oxyanions at aerobic–anaerobic transition zones. Moreover, the LDHS-DGT probe was further used to acquire the dynamic distributions of multi-elements in the plant rhizosphere at a two-dimensional millimeter scale. Compared to treatments of sodium sulfate and mercaptopygorskite fertilization, the addition of elementary S promoted the reduction of sulfate to sulfide along the whole growth stage and thus inhibited the activation of toxic metals in the rice rhizosphere. Collectively, this study provides a tool for convenient measurement of nutrients and metal(loid)s across soil–water/root interfaces at high resolution and thus, a broad application prospect of the tool in sustainable agriculture is expected.

• Buoyancy-driven convection significantly enhances mass transfer rates. • Microwaves enhance 5-hydroxymethyl furfural partitioning in the extractive phase and reduce interphase solubility. • Synergistic "salting out" and microwave effects enhance temperature gradients and partitioning. • COSMO-RS predicts solvents for increased solute partitioning. • Microwaves reduce byproduct formation under temperature gradients. Microwaves (MWs) are a powerful technology for electrifying chemical processing and can enable selective heating, which is impossible in conventional systems. This effect was recently ascribed to enhancing liquid–liquid reactive extractions in biomass derivative chemistry. Expanding upon prior research that showcased MW-induced temperature gradients and their optimization, this study delves into the impact of these gradients on extraction using a combination of experiments and simulations. The findings illustrate that the colder organic phase enforced by the MW heating leads to alterations in solute partitioning and phase behavior. Partitioning can be further tuned by adding salts or by carefully selecting solvents, as demonstrated via COSMO-RS calculations. The colder organic phase also leads to Rayleigh instabilities and active buoyancy-driven mixing. These effects, measured experimentally and simulated in COMSOL, can greatly enhance mass transfer rates in liquid–liquid systems. Under conditions reported in the literature, the MW enhancement to reactive extractions is minimal. Conditions that may lead to more impressive extractions and reactive extractions are suggested. Additionally, it's observed that temperature gradients retard byproduct formation. [ABSTRACT FROM AUTHOR]

The pelagic realm of the dark ocean is characterized by high hydrostatic pressure, low temperature, high-inorganic nutrients, and low organic carbon concentrations. Measurements of metabolic activities of bathypelagic bacteria are often underestimated due to the technological limitations in recovering samples and maintaining them under in situ environmental conditions. Moreover, most of the pressure-retaining samplers, developed by a number of different labs, able to maintain seawater samples at in situ pressure during recovery have remained at the prototype stage, and therefore not available to the scientific community. In this paper, we will describe a ready-to-use pressure-retaining sampler, which can be adapted to use on a CTD-carousel sampler. As well as being able to recover samples under in situ high pressure (up to 60 MPa) we propose a sample processing in equi-pressure mode. Using a piloted pressure generator, we present how to perform sub-sampling and transfer of samples in equi-pressure mode to obtain replicates and perform hyperbaric experiments safely and efficiently (with

The impact of building materials on the environment and the health of occupants is nowadays a priority issue. Ecological construction materials such as earthen materials are currently experiencing a regain of interest due to both ecological and economic factors. The microbial proliferation on indoor materials can induce a deterioration of the building air quality and lead to an increase of health risks for the occupants. The issue of indoor air quality raises questions about the use of earthen building materials and their possible susceptibility to fungal development. The microflora of earthen materials and their ability to grow on such support are indeed poorly studied. This study focused on the quantification of both bacterial and fungal microflora along the manufacturing process. The impact of extreme humidity, simulating a hydric accident, on microflora development was analyzed on the surface and inside earthen bricks. The initial microflora of these materials was dramatically reduced during the manufacturing process, especially after heat treatment for drying. Proliferation of remaining microorganisms was only observed under high humidity condition, in particular for earthen materials with vegetal aggregates. Moreover, in situ samplings were performed on naturally dried earthen materials used in buildings. The characterization of the microbial density revealed a higher microbial density than on manufactured specimens, while microbial concentration and detected taxa seemed mainly related to the room use and building history. These results provide a better understanding of microbial proliferation on these materials.

Our knowledge on biogeochemistry and microbial ecology of marine blue holes is limited due to challenges in collecting multilayered water column and oxycline zones. In this study, we collected samples from 16 water layers in Yongle blue hole (YBH) located in the South China Sea using the in situ microbial filtration and fixation (ISMIFF) apparatus. The microbial communities based on 16S rRNA metagenomic reads for the ISMIFF samples showed high microbial diversity and consistency among samples with similar dissolved oxygen levels. At the same depth of the anoxic layer, the ISMIFF samples were dominated by sulfate-reducing bacteria from Desulfatiglandales (17.96%). The sulfide concentration is the most significant factor that drives the division of microbial communities in YBH, which might support the prevalence of sulfate-reducing microorganisms in the anoxic layers. Our results are different from the microbial community structures of a Niskin sample of this study and the reported samples collected in 2017, in which a high relative abundance of Alteromonadales (26.59%) and Thiomicrospirales (38.13%), and Arcobacteraceae (11.74%) was identified. We therefore demonstrate a new profile of microbial communities in YBH probably due to the effect of sampling and molecular biological methods, which provides new possibilities for further understanding of the material circulation mechanism of blue holes and expanding anoxic marine water zones under global warming., Competing Interests: The authors declare that they have no competing interests., (© 2023 Zhang et al.)

Variations in the phenotypic characteristics of conifer needles is a consequence of genetic evolution that has been widely used in geographic variation and ecological studies. Although many studies are based on an in situ sampling strategy and generally realize the contribution of environmental effects to variation in needle traits, it is still uncertain which needle traits are most influenced by genetic effects and which are most influenced by the environment. Using both a common garden experiment to eliminate environmental heterogeneity and an in situ sampling strategy, we compared 18 Pinus tabuliformis needle traits among 10 geographical populations. Using both sampling strategies, we found significant differences in needle traits among populations and among individuals within populations. Differences in the "among-population" variance component between the two sampling strategies revealed the environmental contribution among natural populations for each trait. The among-population variance in the following traits exceeded 8%: needle length, number of stomata within 2 mm (NS2), number of stomatal lines on the planar side, number of resin canals (RCN) and the resin canal area (RCA). For the stability of needle traits, NS2, RCN, RCA, ratio of the vascular bundle area to the RCA (VBA/RCA), and MA/RCA differed significantly in more than five provenance changes between the common garden populations and natural populations, which may be susceptible to environmental effects. Conversely, the cross-sectional area, mesophyll area (MA), MA/(VBA + RCA), and MA/VBA were phenotypically stable. Geographic variation patterns and systematic relation of needle traits differed between the two sampling strategies, suggesting that in situ sampling results may reflect environmental effects and deviate statistical parameters for genetic study. Future studies of genetic evolution in the context of geographic variation should be based on appropriate sampling strategies and stable phenotypic traits. [ABSTRACT FROM AUTHOR]

The pelagic realm of the dark ocean is characterized by high hydrostatic pressure, low temperature, high-inorganic nutrients, and low organic carbon concentrations. Measurements of metabolic activities of bathypelagic bacteria are often underestimated due to the technological limitations in recovering samples and maintaining them under in situ environmental conditions. Moreover, most of the pressure-retaining samplers, developed by a number of different labs, able to maintain seawater samples at in situ pressure during recovery have remained at the prototype stage, and therefore not available to the scientific community. In this paper, we will describe a ready-to-use pressure-retaining sampler, which can be adapted to use on a CTD-carousel sampler. As well as being able to recover samples under in situ high pressure (up to 60 MPa) we propose a sample processing in equi-pressure mode. Using a piloted pressure generator, we present how to perform sub-sampling and transfer of samples in equi-pressure mode to obtain replicates and perform hyperbaric experiments safely and efficiently (with <2% pressure variability). As proof of concept, we describe a field application (prokaryotic activity measurements and incubation experiment) with samples collected at 3,000m-depth in the Mediterranean Sea. Sampling, sub-sampling, transfer, and incubations were performed under in situ high pressure conditions and compared to those performed following decompression and incubation at atmospheric pressure. Three successive incubations were made for each condition using direct dissolved-oxygen concentration measurements to determine the incubation times. Subsamples were collected at the end of each incubation to monitor the prokaryotic diversity, using 16S-rDNA/rRNA high-throughput sequencing. Our results demonstrated that oxygen consumption by prokaryotes is always higher under in situ conditions than after decompression and incubation at atmospheric pressure. In addition, over time, the variations in the prokaryotic community composition and structure are seen to be driven by the different experimental conditions. Finally, within samples maintained under in situ high pressure conditions, the active (16S rRNA) prokaryotic community was dominated by sequences affiliated with rare families containing piezophilic isolates, such as Oceanospirillaceae or Colwelliaceae. These results demonstrate the biological importance of maintaining in situ conditions during and after sampling in deep-sea environments. [ABSTRACT FROM AUTHOR]

Abstract The deepest point of the oceans is over 10 km depth and is characterized with extremely high hydrostatic pressure. Water sampling from the hadal zone for microbiological studies is therefore difficult. In this study, we demonstrate the application of an in situ microbial filtration and fixation (ISMIFF) apparatus in sampling work from the Challenger Deep. A total of 2300 L hadal waters were filtered by the ISMIFF equipped on a hadal lander during seven deployments. The microbial communities in the hadal samples (>6000 m) collected by the ISMIFF were composed of more heterotrophic Marinimicrobia and less photoautotrophic Prochlorococcus and SAR11 bacteria, compared with those by Niskin bottles. Such a difference in the community structure was not observed in the samples collected by the two methods from ~5000-m depth, indicating an effect of greater depths on sample quality. Our results indicate that the ISMIFF or similar filtration apparatuses are indispensable for hadal water sampling since using Niskin bottles is probably difficult to obtain pristine samples from the hadal zone. Application of the ISMIFF will pave the way to meta-omics studies on the hadal microbes. Highlights • The ISMIFF could obtain pristine microbial samples from the Challenger Deep. • The ISMIFF sampler could filter a large volume of water sample from the hadal zone. • In situ filtration and preservation of microbes at hadal depths may provide high-quality samples for future omics work. [ABSTRACT FROM AUTHOR]

Fungi have an important role in nutrient cycling in most ecosystems on Earth, yet their ecology and functionality in deep continental subsurface remain unknown. Here, we report the first observations of active fungal colonization of mica schist in the deep continental biosphere and the ability of deep subsurface fungi to attach to rock surfaces under in situ conditions in groundwater at 500 and 967 m depth in Precambrian bedrock. We present an in situ subsurface biofilm trap, designed to reveal sessile microbial communities on rock surface in deep continental groundwater, using Outokumpu Deep Drill Hole, in eastern Finland, as a test site. The observed fungal phyla in Outokumpu subsurface were Basidiomycota, Ascomycota, and Mortierellomycota. In addition, significant proportion of the community represented unclassified Fungi. Sessile fungal communities on mica schist surfaces differed from the planktic fungal communities. The main bacterial phyla were Firmicutes, Proteobacteria, and Actinobacteriota. Biofilm formation on rock surfaces is a slow process and our results indicate that fungal and bacterial communities dominate the early surface attachment process, when pristine mineral surfaces are exposed to deep subsurface ecosystems. Various fungi showed statistically significant cross-kingdom correlation with both thiosulfate and sulfate reducing bacteria, e.g., SRB2 with fungi Debaryomyces hansenii.

The coupling of disposable solid-phase microextraction (SPME) with performance reference compounds (PRCs) has been recently introduced to measure time-averaged freely dissolved concentrations ( C free ) of hydrophobic organic contaminants in sediments under laboratory conditions. To explore the use of PRC-SPME for in situ sampling in seawater, disposable PDMS fibers (35-μm and 100-μm coating) preloaded with stable isotope labeled analogues as PRCs were deployed at six stations (each with three depths) in the open ocean of the Palos Verdes Shelf (CA, USA) Superfund site for 33 d to measure C free of DDT and its degradates. The observed values of fractional equilibration ( f eq ) of PRCs were mostly < 0.85, suggesting nonequilibrium conditions at the end of deployment. The observed f eq s for the samplers varied with compound, sampling station and depth, validating the need for calibration to derive accurate C free . The C free values of DDE and DDD determined with PRC-SPME were in good agreement with those previously measured by in situ large-volume water sampling or polyethylene devices. The highest C free in seawater 5 m off the ocean floor was 750 pg L − 1 for o , p ′ -DDE, 2170 pg L − 1 for p , p ′ -DDE, 24 pg L − 1 for o , p ′ -DDD, and 75 pg L − 1 for p , p ′ -DDD. Results of this study demonstrated the feasibility and advantages of using disposable PDMS fiber coupled with PRCs for in situ sampling. [ABSTRACT FROM AUTHOR]

Pyrethroid insecticides are widely used in urban environments, and their occurrence has been recently associated with aquatic toxicity in urban surface streams. Synthetic pyrethroids are strongly hydrophobic compounds, highlighting the importance of the freely dissolved concentration (Cfree), rather than the total chemical concentration, for better prediction of potential effects in aquatic ecosystems. The goal of this study was to develop a simple, robust and field-applicable passive sampling methodology that may be used for in situ monitoring of trace levels of pyrethroids in surface water. Among a range of polymer films, polyethylene film (PE) was found to be the most efficient at absorbing pyrethroids from water. To circumvent the long equilibrium time, 13C-permethrin and bifenthrin-d5 were preloaded on the PE sampler as performance reference compounds (PRC). Desorption of isotope-labeled PRCs was found to be isotropic to the absorption of target analytes. The optimized method was first tested in large circulating tanks simulating various environmental conditions. The derived Cfree values were consistently smaller than the total aqueous concentration in salt water or water containing humic acids. The PE samplers were further deployed at multiple field sites for 7 d in Southern California and analysis demonstrated good monitoring reproducibility and sensitivity under ambient environmental conditions. The developed passive sampler approach is ideal for application for in situ sampling under field conditions, and the use of PRCs allows sampling with short and flexible time intervals. [ABSTRACT FROM AUTHOR]

• The local geochemical concentrations along the depth are obtained in situ. • The effective diffusion coefficients are calculated via the modified model. • The reaction could improve CO 2 transport through the geochemical gradients. • Pressure decay favors the carbonation in the deep zone without much free water. During geological CO 2 storage and utilization, CO 2 plume migration forms widespread static retention regions including the dead-end fractures and pores in the host rock, where the mass transfer is dominated by diffusion. A series of packed column experiments with natural olivine were conducted to investigate how the coupled CO 2 diffusion–reaction process influences the CO 2 transport and the temporal-spatial evolution of carbonate precipitation in diffusion-limited zones. The carbonate precipitations were mainly magnesite, and some dolomite due to the combined effect of carbonate precipitation kinetics and the low Ca content of the solution with Mg enrichment. Compared with the pure diffusion in porous media, the geochemical gradients in the pore solution resulting from the coupled diffusion–reaction interaction promoted mass transfer and broad migration, which led to an increase in effective diffusion coefficients of CO 2 by approximately-one order of magnitude. The free water layer and pressure mode could affect the distribution of carbonate precipitation and the overall sequestration capacity. In particular, the coupled CO 2 diffusion–reaction interaction under pressure decay mode could accelerate the carbonation in the deep region in the water-saturated column. This study advances the fundamental understanding on the transport and reaction of injected CO 2 for mafic and ultramafic formations. [ABSTRACT FROM AUTHOR]

This research is focused on the experimental characterisation of the compressive behaviour of masonry in existing buildings. The proposed technique is based on in situ core drilling of masonry members. Two walls were built making use of terracotta handmade bricks and lime mortar, without cement, to reproduce a low-strength historical masonry. Core samples were extracted from the walls and then regularized to perform a non-standard compression test in the laboratory. Stack-bonded prisms were also tested under compression. A direct comparison is made between the results from the proposed non-standard tests on core samples and the tests suggested by the available standards on prismatic samples. The proposed minor destructive technique shows to be effective for the mechanical characterisation of existing masonry structures, including historical ones. [ABSTRACT FROM AUTHOR]

For mapping, quantifying and monitoring regional and global forest health, satellite remote sensing provides fundamental data for the observation of spatial and temporal forest patterns and processes. While new remote-sensing technologies are able to detect forest data in high quality and large quantity, operational applications are still limited by deficits of in situ verification. In situ sampling data as input is required in order to add value to physical imaging remote sensing observations and possibilities to interlink the forest health assessment with biotic and abiotic factors. Numerous methods on how to link remote sensing and in situ data have been presented in the scientific literature using e.g. empirical and physical-based models. In situ data differs in type, quality and quantity between case studies. The irregular subsets of in situ data availability limit the exploitation of available satellite remote sensing data. To achieve a broad implementation of satellite remote sensing data in forest monitoring and management, a standardization of in situ data, workflows and products is essential and necessary for user acceptance. The key focus of the review is a discussion of concept and is designed to bridge gaps of understanding between forestry and remote sensing science community. Methodological approaches for in situ/remote-sensing implementation are organized and evaluated with respect to qualifying for forest monitoring. Research gaps and recommendations for standardization of remote-sensing based products are discussed. Concluding the importance of outstanding organizational work to provide a legally accepted framework for new information products in forestry are highlighted. [ABSTRACT FROM AUTHOR]

Estrogenic pollution and its control in aquatic systems have drawn substantial attention around the world. The chemical and biological assessment approaches currently utilized in the laboratory or field cannot give an integrated assessment of the pollution when used separately. In this study, in situ chemical and biological methods were combined to detect pollution in a water recycling system. Data for the water quality index (WQI) demonstrated that the water treatment resulted in the decline of pollution from upstream to downstream. Wild male Nile tilapia, Oreochromis niloticus , was sampled in June and September. The concentrations of four common endocrine disrupting chemicals (EDCs) were determined in the tilapia liver by chromatographic analysis methods. The level of 17β-estradiol (E2) declined from upstream to downstream in both months. In contrast, the levels of bisphenol A (BPA), di-(2-ethylhcxyl) phthalate (DEHP), and perfluorooctane sulfonate (PFOS) did not display this declining tendency. The highest relative expression of vitellogenin 1 (VTG1) was observed in tilapia from upstream, then the level significantly decreased along the water system. The relative expression levels of CYP1A1 in the water system were also significantly higher than that of the control. However, no declining trend could be observed along the water system. The change of VTG1 expression corresponded well with that of E2 levels in the tilapia liver. Overall, our study assessed the pollution by endocrine disruptors using chemical and biological data with good correspondence. This study also demonstrated the effectiveness of the water recycling system in eliminating estrogen pollution in municipal sewage. [ABSTRACT FROM AUTHOR]

This article presents an experimental study aimed at the characterization of the mechanical behavior of existing masonry. The research proposes a methodology based on the in situ core drilling of existing masonry members, made of clay brick and low-strength lime mortar. The obtained cylindrical samples, with different diameters, are tested in the laboratory to derive the compression and frictional response of the composite material and the components (units, mortar). This article addresses the main issues related to the extraction of cylindrical specimens: the testing and the interpretation of results. The proposed minor destructive technique is suitable for existing masonry structures and especially for those of the built cultural heritage, since a direct estimation of the mechanical parameters can be obtained without damaging excessively the historical structure. [ABSTRACT FROM PUBLISHER]

For mapping, quantifying and monitoring regional and global forest health, satellite remote sensing provides fundamental data for the observation of spatial and temporal forest patterns and processes. While new remote-sensing technologies are able to detect forest data in high quality and large quantity, operational applications are still limited by deficits of in situ verification. In situ sampling data as input is required in order to add value to physical imaging remote sensing observations and possibilities to interlink the forest health assessment with biotic and abiotic factors. Numerous methods on how to link remote sensing and in situ data have been presented in the scientific literature using e.g. empirical and physical-based models. In situ data differs in type, quality and quantity between case studies. The irregular subsets of in situ data availability limit the exploitation of available satellite remote sensing data. To achieve a broad implementation of satellite remote sensing data in forest monitoring and management, a standardization of in situ data, workflows and products is essential and necessary for user acceptance. The key focus of the review is a discussion of concept and is designed to bridge gaps of understanding between forestry and remote sensing science community. Methodological approaches for in situ/remote-sensing implementation are organized and evaluated with respect to qualifying for forest monitoring. Research gaps and recommendations for standardization of remote-sensing based products are discussed. Concluding the importance of outstanding organizational work to provide a legally accepted framework for new information products in forestry are highlighted.

Highlights: [•] High hydrogen yields in partial oxidation of ethanol to hydrogen on Rh/Al2O3. [•] Axial concentration and temperature profiles inside monolithic channels measured. [•] Total/partial oxidation zone at catalyst entrance followed by reforming zone. [•] Homogeneous gas-phase reactions in front of the catalyst produce acetaldehyde. [•] Not all channels behave alike due to temperature gradient across the monolith. [ABSTRACT FROM AUTHOR]

Purpose: Understanding of the role of low molecular weight organic anions (OAs) in structuring rhizosphere microbial communities in situ is limited due to challenges associated with sampling. Improved techniques are needed for such studies. Methods: This study used in situ and destructive sampling techniques and compared two exudate extraction methods [anion exchange membrane (AEM) capturing and water extraction] from rhizosphere and non-rhizosphere samples of genetically modified (GM) and control Pinus radiata D. Don trees grown in large-scale rhizotrons for ~10 months. Metabolically active soil microbial communities were analysed using rRNA-DGGE. Results: Recovery of eight out of 12 anions was influenced by extraction methods, and in situ sampling using AEM was shown to be the most efficient method. Only minor differences were detected in OAs in root exudates collected from the GM and control trees. Significant differences in α-Proteobacterial and Pseudomonas communities were associated with the two tree lines in the topsoil at both sampling events. Additional differences in β-Proteobacterial and fungal communities between tree lines were detected in the rhizosphere using destructive sampling. Conclusion: This study demonstrated that in situ sampling was superior to destructive sampling for the efficient collection of root exudates and analysis of associated rhizosphere microbial communities. [ABSTRACT FROM AUTHOR]

Abstract: An in situ application of solid-phase microextraction (SPME) as a sampling and sample preparation method coupled to HPLC-MS/MS for direct monitoring of ochratoxin A (OTA) distribution at different locations in a single cheese piece is proposed. To be suited to the acidic analyte, the extraction phase (carbon-tape SPME fiber) was acidified with aqueous solution of HCl at pH 2, instead of the traditional sample pre-treatment with acids before SPME sampling. For calibration, kinetic on-fiber-standardization was used, which allowed the use of short sampling time (20min) and accurate quantification of the OTA in the semi-solid cheese sample. In addition, the traditional kinetic calibration that used deuterated compounds as standards was extended to use a non-deuterated analogue ochratoxin B (OTB) as the standard of the analyte OTA, which was supported by both theoretical discussion and experimental verification. Finally, the miniaturized SPME fiber was adopted so that the concentration distribution of OTA in a small-sized cheese piece could be directly probed. The detection limit of the resulting SPME method in semi-solid gel was 1.5ng/mL and the linear range was 3.5–500ng/mL. The SPME–LC-MS/MS method showed good precision (RSD: ∼10%) and accuracy (relative recovery: 93%) in the gel model. The direct cheese analysis showed comparable accuracy and precision to the established liquid extraction. As a result, the developed in situ SPME–LC-MS/MS method was sensitive, simple, accurate and applicable for the analysis of complicated lipid-rich samples such as cheese. [Copyright &y& Elsevier]

The biogeochemistry of multi-elements, such as sulfur (S), phosphorus (P) and arsenic (As), is interlinked especially at interfaces of soil/sediment–water and plant rhizosphere. To explore the biogeochemical behavior of multi-elements such as S-P-As at interfaces, an in situ and high-resolution technology is required. In this study, we developed an in situ probe (LDHs-DGT) based on the diffusive gradients in thin-films technique using a single binding layer to realize the co-measurement of multi-elements including sulfide and oxyanions. Mg-Al layered double hydroxides (LDHs) were synthesized and incorporated into the probe's binding layer. Laboratorial characterization showed that the LDHs-DGT probe had a high capacity for sulfide, phosphate and arsenate and can effectively determine their levels across a wide range of solution conditions, i.e., pH from 5 to 8 and ionic strengths from 0.005–0.01 mol L−1 NaNO3. The application potential of the LDHS-DGT probe in capturing the concentration profiles of sulfide and oxyanions across the soil/sediment–water interface at a centimeter scale was demonstrated. The synchronous co-variations of labile sulfide and phosphate were observed along an intact river sediment core, demonstrating the redox driven behaviors of oxyanions at aerobic–anaerobic transition zones. Moreover, the LDHS-DGT probe was further used to acquire the dynamic distributions of multi-elements in the plant rhizosphere at a two-dimensional millimeter scale. Compared to treatments of sodium sulfate and mercaptopygorskite fertilization, the addition of elementary S promoted the reduction of sulfate to sulfide along the whole growth stage and thus inhibited the activation of toxic metals in the rice rhizosphere. Collectively, this study provides a tool for convenient measurement of nutrients and metal(loid)s across soil–water/root interfaces at high resolution and thus, a broad application prospect of the tool in sustainable agriculture is expected. [ABSTRACT FROM AUTHOR]

Large scale reclamation works in coastal areas of the Nakdong River plain are at various stages of progress, since early 1990's on in-situ soft marine clay deposits. These deposits are of the order of 30 to 40 m thick. A realistic rapid characterization of soft ground would ensure success of any reclamation work in this area. In order to cope with the work carried out with different agencies, it is desirable to evolve a systematic methodology. In this study, engineering properties of clays at three coastal areas, Gadukdo, Noksan and Shinho, have been generated. The analysis of data has been done within the framework of classical developments in soil mechanics. Analysis has also been made by making use of the recent developments in dealing with soft clays. The dominant factors, namely, stress, time, and environment influencing the response of clay to loading are identified. [ABSTRACT FROM AUTHOR]

Growth characteristics of silica particles have been studied experimentally using in situ particle sampling technique from H2/O2/Tetraethylorthosilicate (TEOS) diffusion flame with carefully devised sampling probe. The particle morphology and the size comparisons are made between the particles sampled by the local thermophoretic method from the inside of the flame and by the electrostatic collector sampling method after the dilution sampling probe. The Transmission Electron Microscope (TEM) image processed data of these two sampling techniques are compared with Scanning Mobility Particle Sizer (SMPS) measurement. TEM image analysis of two sampling methods showed a good agreement with SMPS measurement. The effects of flame conditions and TEOS flow rates on silica particle size distributions are also investigated using the new particle dilution sampling probe. It is found that the particle size distribution characteristics and morphology are mostly governed by the coagulation process and sintering process in the flame. As the flame temperature increases, the effect of coalescence or sintering becomes an important particle growth mechanism which reduces the coagulation process. However, if the flame temperature is not high enough to sinter the aggregated particles then the coagulation process is a dominant particle growth mechanism. In a certain flame condition a secondary particle formation is observed which results in a bimodal particle size distribution. [ABSTRACT FROM AUTHOR]

A widE-Ranging investigation of the first COVID-19 LOCkdown effects on the atmospheric composition in five Italian Urban Sites (AER–LOCUS) has been carried out and is presented in this study. The analysis uses particle and gas concentrations from surface in situ sampling, column aerosol and gas properties from photometer/spectrometers, and satellite NO 2 determinations at five sites distributed over the whole Italian territory: Aosta, Milan, Bologna, Rome, and Taranto. These data are related to meteorological conditions to identify the numerous events of long-range transport and separate local from remote influences. Four different types of long-range transport over Italy are identified during the lockdown period, affecting PM 10 , PM 2.5 , and NO 2 concentrations, and aerosol optical depths: fires plumes from Eastern Europe and Montenegro, dust from the Caspian area and from the Sahara, and pollution from the Po Valley. Once the long-range transport events are identified and excluded, the variation of gas and particle concentrations occurring during the containment period is calculated with respect to the period 2015–2019. A general decrease of PM 10 (ranging from a maximum of −52% in Aosta to a minimum of −4% in Taranto), PM 2.5 (from −46% in Aosta and Milan to −0.6% in Bologna), BC (from −77% in Aosta to −25% in Milan), NO 2 (from −72% in Rome to −4% in Taranto), and benzene (about −50%) concentration is found. A positive variation of PM 2.5 is conversely found during March in the southern sites due to some stagnation events, and a strong increase of benzene (up to +104%) in the industrial area of Taranto. Ozone is found to increase by an average of about 30% in all sites. The removal of the long-range transport contributions affects the variations with respect to the reference period reducing the concentrations by up to 22% for PM 10 and 29% for PM 2.5 in the northern sites, and 18% for PM 10 and 16% for PM 2.5 in the southern sites. For NO 2 the reduction due to the removal is up to 14% in Milan and 6% in the southern sites, while for the aerosol optical depth it is up to 70% in Aosta and 50% in Rome. [Display omitted] • Pollutant concentrations during the lockdown are affected by long-range transports of air masses from outside. • The long-range transports are spotted by ground/space remote sensing, in situ sampling and meteorological analysis. • The effects on the local emissions due only to the restrictions are identified. • The relative variation of gas and particle concentrations with respect to the period 2015–2019 is calculated. • The removal of the long-range transports leads to a greater reduction of the concentrations. [ABSTRACT FROM AUTHOR]

In this report, a flame spray pyrolysis setup has been examined with various in situ extraction methods of particle samples along the flame axis. First, two precursor formulations leading to the formation of iron oxide nanoparticles were used in a standardized SpraySyn burner system, and the final particle outcome was characterized by a broad range of established powder characterization techniques (TEM/HRTEM, SAXS, XRD, BET). The characterization of the powder products evidenced that mostly homogeneous gas-to-particle conversion takes place when applying an acidic precursor solution, whereas the absence of the acid leads to a dominant droplet-to-particle pathway. Our study indicates that a droplet-to-particle-pathway could be present even when processing the acidic formulation. However, even if a secondary pathway might take place in this case as well, it is not dominant and nearly negligible. Subsequently, the in situ particle structure evolution was investigated for the dominant gas-to-particle pathway, and particles were extracted along the flame axis for online SMPS and offline TEM/HRTEM analysis. Due to the highly reactive conditions within the flame (high temperatures, turbulent flow field, high particle number concentrations), the extraction of representative samples from spray flames is challenging. In order to handle the reactive conditions, two extraction techniques were tailored in this report. To extract an aerosol sample within the flame for SMPS measurement, a Hole in a Tube probe was adjusted. Thus, the mobility particle diameter as well as the corresponding distribution widths were obtained at different heights above the burner along the flame axis. For TEM/HRTEM image analysis, particle samples were collected thermophoretically by means of a tailored shutter system. Since all sampling grids were protected until reaching the flame axis and due to the low sampling time, momentary captures of local particle structures could be extracted precisely. The particle morphologies have clearly shown an evolution from spherical and paired particles in the flame center to fractal and compact agglomerates at later synthesis stages. • In situ sampling via Hole-in-a-Tube probes from Flame Sprays. • Sampling via shutter systems with precise local shorttime sampling for HRTEM analysis. • Flame spray pyrolysis gas-to-particle route results in a variety of extremely small particle structures. • Observation of droplet-to particle routes for iron nitrate based precursor formulations. • Insights into the particle structure evolution along the flame axis reveal locally dominating formation mechanisms. [ABSTRACT FROM AUTHOR]

Resolving chemical/biological drivers of P behavior around lowland/flooded rice roots remains a challenge because of the heterogeneity of the plant-soil interactions, compounded by sampling and analytical constraints. High-spatial-resolution (sub-mm) visualization enables these processes to be isolated, characterized, and deciphered. Here, three advanced soil imaging systems, diffusive gradients in thin-film technique coupled with laser ablation-ICPMS (DGT-LA-ICPMS), O 2 planar optode, and soil zymography, were integrated. This trio of approaches was then applied to a rice life cycle study to quantify solute-P supply, through two dimensions, in situ , and low-disturbance high-resolution (HR) chemical imaging. This allowed mechanisms of P release to be delineated by O 2 , Fe, and phosphatase activity mapping at the same scale. HR-DGT revealed P depletion around both living and dead rice roots but with highly spatially variable Fe/P ratios (∼0.2-12.0) which aligned with changing redox conditions and root activities. Partnering of HR-DGT and soil zymography revealed concurrent P depletion and phosphatase hotspots in the rhizosphere and detritusphere zones (Mantel: 0.610-0.810, p < 0.01). This close affinity between these responses (Pearson correlation: -0.265 to -0.660, p < 0.01) cross-validates the measurements and reaffirms that P depletion stimulates phosphatase activity and P org mineralization. The μ-scale biogeochemical landscape of rice rhizospheres and detritusphere, as documented here, needs greater consideration when implementing interventions to improve sustainable P nutrition.

The diffusive gradients in thin films (DGT) technique has been successfully and widely applied to investigate the labile fractions of inorganic contaminants in soils and sediments, but there have been almost no applications to organic contaminants. Here we developed and tested the approach for the pesticide Atrazine (ATR) in a controlled soil experiment and in situ in an intact lake sediment core. The soil study explored the relationships between soil solution, DGT measured labile ATR and solvent extractable ATR in dosed soils of different organic matter, pH status and incubation times. The results are further interpreted using the DIFS (DGT-induced fluxes in soils and sediments) model. Resupply of ATR to the soil solution was partially sustained by the solid phase in all the soils. This was due to small labile pool size and slow kinetics, with soil pH being an important controlling factor. The in situ sediment study successfully used a DGT probe to examine labile ATR distribution through the core on the subcm scale. It demonstrated-for the first time-an easy to use in situ technique to investigate the effects of redox on resupply kinetics and biogeochemical processes of trace organic contaminants in sediments.

Fungi have an important role in nutrient cycling in most ecosystems on Earth, yet their ecology and functionality in deep continental subsurface remain unknown. Here, we report the first observations of active fungal colonization of mica schist in the deep continental biosphere and the ability of deep subsurface fungi to attach to rock surfaces under in situ conditions in groundwater at 500 and 967 m depth in Precambrian bedrock. We present an in situ subsurface biofilm trap, designed to reveal sessile microbial communities on rock surface in deep continental groundwater, using Outokumpu Deep Drill Hole, in eastern Finland, as a test site. The observed fungal phyla in Outokumpu subsurface were Basidiomycota, Ascomycota, and Mortierellomycota. In addition, significant proportion of the community represented unclassified Fungi. Sessile fungal communities on mica schist surfaces differed from the planktic fungal communities. The main bacterial phyla were Firmicutes, Proteobacteria, and Actinobacteriota. Biofilm formation on rock surfaces is a slow process and our results indicate that fungal and bacterial communities dominate the early surface attachment process, when pristine mineral surfaces are exposed to deep subsurface ecosystems. Various fungi showed statistically significant cross-kingdom correlation with both thiosulfate and sulfate reducing bacteria, e.g., SRB2 with fungi Debaryomyces hansenii.

Plants produce volatile organic compounds (VOCs) with diverse structures and functions, which change in response to environmental stimuli and have important consequences for interactions with other organisms. To understand these changes, in situ sampling is necessary. In contrast to dynamic headspace (DHS), which is the most often employed method, direct contact sampling employing a magnetic stir bar held in place by a magnet eliminates artifacts produced by enclosing plant materials in glass or plastic chambers. Direct-contact sorptive extraction (DCSE) using polydimethylsiloxane coated stir bars (Twisters) coated stir bars is more sensitive than DHS, captures a wider range of compounds, minimizes VOC collection from neighboring plants, and distinguishes the effects of herbivory in controlled and field conditions. Because DCSE is relatively inexpensive and simple to employ, scalability of field trials can be expanded concomitant with increased sample replication. The sensitivity of DCSE combined with the spectral deconvolution data analysis software makes the two ideal for comprehensive, in situ profiling of plant volatiles.