Scientific Publications

Refractory Black carbon (rBC) emitted from the combustion of biomass and fossil fuels plays an important role in the climate system. In this study, we established a record of the rBC concentration spanning 1932-2013 from an ice core retrieved from the Chongce ice cap of the West Kunlun Mountains in the western Tibetan Plateau. The record showed an increasing trend since the 1980s. The mean concentration of rBC was 2.66 ng g−1 before 1980 and 5.33 ng g−1 since 1980. The significant increase since the 1980s was very different from similar records from European ice cores. An analysis of atmospheric circulation and backward trajectories suggested that former USSR, the Middle East, and South Asia were the most likely source regions for the rBC deposited at the Chongce ice cap. This conclusion was also supported by the historical emission data in these regions. Phase analysis indicated that high rBC concentrations were closely associated with drought-induced biomass burning in the rBC so...

A highly selective and efficient method based on the use of graphene oxide (GO) and a magnetic ionic liquid (MIL) for dispersive micro-solid phase extraction (D-μ-SPE) was developed for inorganic Sb speciation analysis. In this work, Sb(III) species was selectively complexed with sodium diethyldithiocarbamate (DDTC) and retained on 3 mg of GO. Afterwards, 40 μL of the MIL trihexyl(tetradecyl)phosphonium hexachlorodysprosiate(III) ([P6,6,6,14]3DyCl6) were added to instantly magnetize the sorbent surface followed by its separation using a magnetic rod. Then, the aqueous phase containing only Sb(V) was directly analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Total Sb concentration was obtained by direct introduction of the sample into ICP-MS instrument. Thus, Sb(III) was calculated based on the difference between the concentrations of total inorganic Sb and Sb(V). Extraction conditions were optimized by a multivariate study yielding a 99.7% extraction efficiency for S...

Antimony (Sb) concentrations were measured in wet atmospheric deposition at 10 high-elevation sites in the Czech Republic (Central Europe) during three winter seasons (2009-2011). Soluble and insoluble Sb forms were quantified in snow (vertical deposition) and rime (horizontal deposition) on mountain summits located equidistantly near the Czech borders with Austria, Germany and Poland. The highest Sb concentrations were found in the soluble form in rime (0.47 μg L-1), while the lowest Sb concentrations were those in the insoluble form in snow (0.017 μg L-1). The estimated average Sb deposition rate in Central Europe amounted to 1.3. 10-4 g m-2 yr-1. Most Sb was deposited in the soluble form in snow (7.9. 10-5 g m-2 yr-1), followed by the soluble form in rime (3.5. 10-5 g m-2 yr-1). The corresponding insoluble fraction contained less Sb, namely 1.2. 10-5 g m-2 yr-1 in snow and 2.3. 10-6 g m-2 yr-1 in rime. The average Sb deposition in Central Europe, measured at an altit...

The environmental fate of the frequently used broad-spectrum β-lactam antibiotic amoxicillin (AMX) is of high concern regarding the potential evolution of antimicrobial resistance (AMR). Moreover, it is known that AMX is prone to hydrolysis, yielding a variety of hydrolysis products (HPs) with yet unknown effects. Studies to identify those HPs and investigate their formation mechanisms have been reported but a long-term study on their stability in real water samples was missing. In this regard, we investigated the hydrolysis of AMX at two concentration levels in four distinct water types under three different storage conditions over two months. Concentrations of AMX and four relevant HPs were monitored by an LC-MS/MS method revealing pronounced differences in the hydrolysis rate of AMX in tap water and mineral water on the one hand (fast) and surface water on the other (slow). In this context, the occurrence, relative intensities, and stability of certain HPs are more dependent on the...

In this paper, we present mineralogical, whole-rock geochemical, Sr and Pb isotopic, and zircon trace elemental and U-Pb geochronological data for the newly-discovered Pengco listvenite in central Tibet, in an attempt to probe the petrogenesis of listvenite and the tectonic environment. The listvenite is composed of magnesite, quartz and minor dolomite and Cr-spinel. Chemistry of abundant protogenetic Cr-spinel in the Pengco listvenite as well as the whole-rock Cr and Ni concentrations and low rare-earth element contents indicates the harzburgite protolith. Addition of Ca and K and redistribution of Si at sample scale suggest that the formation of Pengco listvenite was not an isochemical process. Serpentinization could partly accounts for the enrichments in some fluid mobile elements before listvenitization. The εHf(t) values of xenocrystic zircons in the Pengco listvenite are dominantly negative, suggesting a continental crustal source. The zircon age spectra and high whole-rock init...

It remains unclear how the suspended non-fed bivalve mariculture will alter the coastal transfer and cleaning process of trace elements, the non-degradable contaminants, which have been reported to accumulate in sediment from bivalve mariculture areas. Herein, we set up a field in situ comparative test in the suspended oyster (Crassostrea plicatula) farming area (OF) and reference area (RA) of Xiangshan Bay to verify our hypothesis that the biodepositon of suspended oysters would consolidate trace elements from the water column and transport them to the sediment. Distribution of trace elements in multiple media of biodeposits (BDs), settling particles (SPs), sediments (SEs), and seawater demonstrate that the accelerated deposition of BDs which enriched trace elements from the water column by oysters filtering suspended particles led to trace elements accumulation in SEs from OF. Additionally, As, Cd, Co, Cr, Cu, Ni, V, and Zn were strongly regulated by this process with significant (p�...

The petrogenesis and dynamic setting of Archean tonalite-trondhjemite-granodiorite (TTG) is widely debated. As a typical Archean terrane in the northeastern North China Craton (NCC), the southern Jilin Province area underwent multi-stage magmatism during the Neoarchean and is therefore a promising region in which to track the Neoarchean evolution of the NCC. This study investigates the petrogenesis of late Neoarchean TTGs and associated monzogranites and their tectonic implications. Zircon U-Pb dating results suggest that the TTGs and monzogranites have emplacement ages of 2.55-2.52 and 2.53-2.51 Ga, respectively. The TTGs have variable SiO2 (61.7-73.3 wt%) and MgO (0.66-2.74 wt%) contents and Mg# values of 33-50. Most have high Sr and low Y and Yb contents, with high Sr/Y and (La/Yb)N ratios. The TTGs have variable εHf(t) (+0.7 to + 8) and εNd(t) (−2.77 to + 2.79) values. These characteristics, together with the results of thermodynamic partial-melting modelling, indicate that the...

Given the increasing need to protect vulnerable freshwater ecosystems and make them more resilient to human use and climate change, biomonitoring of the hyporheic zone (HZ), which plays a critical role in pollution attenuation, is essential. The aim of the present study was to assess the potential of the amphipod species Synurella ambulans as a bioindicator of metal contamination in the HZ of the Sava River (Croatia). Amphipods were collected during the four seasons at two sampling sites (average sampling depth 55 cm) differing in type (agricultural and urban) and intensity (diffuse and point source contamination) of anthropogenic influence, one located upstream (Medsave), and the other downstream (Jarun) of the wastewater treatment plant discharge. Concentrations of Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Rb, Sn, Zn, Ca, K, Mg and Na were measured in the interstitial water, sediments and specimens of S. ambulans by HR ICP-MS. Physicochemical parameters (temperature, DO, O2 saturation, p...

The timing of porosity destruction in reservoir rock is key for hydrocarbon exploration. This study constrains the porosity destruction of the syn-rift Barremian (130-125 Ma) TOCA Fm. from one drill core located in the Lower Congo basin (West African passive margin). We apply an unprecedented multi-proxy approach to reconstruct the absolute timing of mechanical compaction, pressure-solution and cementation as well as their relative contribution to porosity destruction. LA-ICP-MS U-Pb geochronology combined with petrological observations suggest that the main interstitial diagenetic cement C1 filling the porosity of the packstones and dated 127.4 ± 2.2 to 119.4 ± 6.4 Ma predates pressure-solution. The quantification of the cement distribution by image analysis indicates that C1 clogged ∼30% of the initial porosity before the strata were buried at 400 m. We assume that the early cementation limited the effect of mechanical compaction on porosity reduction which is estimated to ∼2% ...

Atmospheric particulate matter (PM) pollution is one of the most serious global environmental problems, regarded to be associated with a wide range of diseases, e.g., cardiovascular disease, lung cancer. Mitigation of PM impact is hampered by highly uncertain source apportionment, which requires a valuable tracer to identify and constrain the emissions with high precision. Recently, with the rapid development of multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS), non-traditional stable isotopes, e.g. silicon (Si), iron (Fe), copper (Cu), zinc (Zn), lead (Pb), mercury (Hg), strontium (Sr), neodymium (Nd), have been used as valuable tracers for source apportionment of PM. Here, we summarized the latest advances in the analytical method and applications of non-traditional stable isotopes in source tracing of PM. Considering the limitation of the complex matrix effect of PM samples, a particular focus lies on a discussion of isotope analysis of PM, e.g., sample pretre...

There is increasing interest in assessing the impact of whales on nutrient and carbon cycling in the ocean. By fertilising surface waters with nutrient-rich faeces, whales may stimulate primary production and thus carbon uptake, but robust assessments of such effects are lacking. Based on the analysis of faeces collected from minke whales (n = 31) off Svalbard, Norway, this study quantified the concentration of macro and micronutrients in whale faeces prior to their release in seawater. Concentrations of the macronutrients nitrogen (N) and phosphorous (P) in minke whale faeces were 50.1 ± 10.3 and 70.9 ± 12.1 g kg−1 dry weight, respectively, while the most important micronutrients were zinc (Zn), iron (Fe), manganese (Mn) and copper (Cu). By combining measured faecal nutrient concentrations with estimated prey-consumption and prey-assimilation rates, we calculate that the current population of approximately 15, 000 individuals in the small management area (SMA) of Svalbard defecate...

The speciation of dissolved trace metals is important due to its closely linkage with toxicity and bioavailability in seawater. We investigate the speciation of dissolved Pb (DPb) and Cd (DCd), and their spatial distributions in the Yellow Sea and Bohai Sea, China. The results showed that the organic complexation of DPb and DCd accounted for 35 ± 14 % and 75 ± 10 % of their dissolved concentrations, respectively. The measured free ion activity of Cd ({Cd2 +}) and organic ligand concentration of Cd ([LCd]) were highest near the Yellow River mouth, where the free ion activity of Pb ({Pb2+}) were also found to be the highest. In this study, both {Pb2+} and {Cd2+} did not exceed the toxicity threshold, and they were identified not toxic in the waters of the Yellow Sea and Bohai Seas, but biological accumulation effects potentially exist....

Whether Archean tectonics were horizontally or vertically dominated is controversially discussed because arguments bear on the kinematics and thermal state of the Archean mantle and constrain the mode of formation of the earliest continental crust. Highly deformed strata of Archean greenstone belts figure prominently in this debate because they record long periods of time and multiple deformation phases. Among the best-preserved greenstone belts counts the Barberton Greenstone Belt (BGB) of southern Africa. Geological mapping of part of the southern BGB in Eswatini (Swaziland), combined with U-Pb zircon dating, shows that the region preserves a tightly re-folded imbricate thrust stack in which metavolcanic and -volcaniclastic strata of the Onverwacht Group, deposited at 3.34-3.29 Ga, have been thrust on top of ca. 3.22 Ga siliciclastic strata of the Moodies Group. The structurally highest element, the Malolotsha Syncline, forms a tectonic klippe of substantial size and is >1,450 m thic...

Early animals experienced multiple-phase radiations and extinctions from the late Ediacaran to early Cambrian. Oxygen likely played an important role in these evolutionary events, but detailed marine redox evolution during this period remains highly debated. The emerging vanadium (V) isotope system can better capture short-term perturbations to global ocean redox conditions. In this study, we analyzed V isotope compositions (V) of organic-rich cherts and black shales deposited from the late Ediacaran to early Cambrian (ca. 560-518 Ma) in the Yangtze Block, South China. The robust positive correlation between the V values and previously reported Mo values validates V isotope system as a paleo-oxybarometer. The continuously temporal open-ocean seawater V variation is reconstructed from the sedimentary V records. The results suggest that the ocean experienced a rapid transition from expansive euxinia at ca. 560-553 Ma to widespread oxygenation likely reaching the modern level at ca. 552-5...

Inorganic phosphate (Pi) and phosphorus (P) homeostasis are essential for plant growth and yield, and reliable detection of dynamic Pi/P in different tissues is important for studying their biological functions. Here, we report a combined protocol for rapid determination of Pi/P levels. We first perform 31P NMR assay to reveal the intracellular Pi distribution and then dissect the level of Pi/P by the chromogenic reaction and ICP-MS analysis. Finally, we take μXRF element fluorescence assay to achieve the visual P distribution. For complete details on the use and execution of this protocol, please refer to Ma et al. (2021)....

p66Shc governs outcomes for many pathologies, including endothelial dysfunction, coronary artery disease (CAD), and ischemia/reperfusion injuries (IRI). During cardiovascular insults, p66Shc exacerbates reactive oxygen species (ROS) accumulation, which increases pro-apoptotic responses and worsens clinical outcomes. IRI clinical severity is coupled tight enough to p66Shc expression and ROS activity that p66Shc acts as a biomarker for CAD and IRIs. Inhibiting p66Shcmediated ROS accumulation therefore has high therapeutic potential in cardiovascular pathology. Others have shown that p66Shc ROS function is coupled to an unclear interaction with cytochrome c (cyt c) that increases either superoxide anion radical or H2O2 measurements. This has generated confusion about whether p66Shc produces radical or non-radical ROS, an important physiological distinction. Our findings resolve these discrepancies by identifying a previously unknown p66Shc function that describes how p66Shc causes H2O2 ac...

The Zn content in cereal seeds is an important trait for crop production as well as for human health. However, little is known about how Zn is loaded to plant seeds. Here, through a genome-wide association study (GWAS), we identify the Zn-NA (nicotianamine) transporter gene ZmYSL2 that is responsible for loading Zn to maize kernels. High promoter sequence variation in ZmYSL2 most likely drives the natural variation in Zn concentrations in maize kernels. ZmYSL2 is specifically localized on the plasma membrane facing the maternal tissue of the basal endosperm transfer cell layer (BETL) and functions in loading Zn-NA into the BETL. Overexpression of ZmYSL2 increases the Zn concentration in the kernels by 31.6%, which achieves the goal of Zn biofortification of maize. These findings resolve the mystery underlying the loading of Zn into plant seeds, providing an efficient strategy for breeding or engineering maize varieties with enriched Zn nutrition....

During the last African Humid Period (AHP; 15-5 ka), many lakes in the East African Rift System (EARS) experienced pronounced lake-level variations that dramatically transformed the hydrological landscape. Currently dry, saline or marshy-wetland terminal lakes became vast waterbodies, interconnected via overflow sills resulting in the formation of a several thousand-kilometre-long chain of lakes in the EARS. A quantitative, process-based understanding of these hydrological systems can advance our interpretation of past hydroclimate variability from proxy records. Here, we provide a critical modern hydrological dataset for the data-sparse Lake Chew Bahir basin in southern Ethiopia. Driven by modern data, an isotope-enabled hydro-balance model was developed to assess how increases in rainfall modulate δ18O and 87Sr/86Sr variability. Considering a terminal Lake Chew Bahir scenario, humid conditions resulted in higher lake δ18O (∼+14‰) due to increased evaporation and longer water re...

Phosphorus (P) is an essential element for all organisms. Because P fertilizers are a non-renewable resource and high fixation in soils, sustainable agriculture requires researchers to improve crop P acquisition efficiency. Here, we report a strong association signal at a locus of CPU1 (component of phosphorus uptake 1), from a genome-wide association study of P acquisition efficiency in a soybean core collection grown in the field. A SEC12-like gene, GmPHF1, is identified as the causal gene for CPU1. GmPHF1 facilitates the ER (endoplasmic reticulum) exit of the phosphate transporter, GmPT4, to the plasma membrane of root epidermal cells. A common SNP in an upstream open reading frame (uORF) of GmPHF1, which alters the abundance of GmPHF1 in a tissue-specific manner, contributes to P acquisition diversity in soybean. A natural genetic variation conditions diversity in soybean P acquisition, which can be used to develop P-efficient soybean genotypes....

Due to the advent of various biologics like antibodies, proteins, cells, viruses, and extracellular vesicles as biomarkers for disease diagnosis, progression, and as therapeutics, there exists a need to have a simple and ready to use radiolabeling synthon to enable noninvasive imaging trafficking studies. Previously, we reported [89Zr]zirconium-p-isothiocyanatobenzyl-desferrioxamine ([89Zr]Zr-DBN) as a synthon for the radiolabeling of biologics to allow PET imaging of cell trafficking. In this study, we focused on improving the molar activity (Am) of [89Zr]Zr-DBN, by enhancing 89Zr production on a low-energy cyclotron and developing a new reverse phase HPLC method to purify [89Zr]Zr-DBN. To enhance 89Zr production, a new solid target was designed, and production yield was optimized by varying, thickness of yttrium foil, beam current, irradiation duration and proton beam energy. After optimization, 4.78±0.33 GBq (129.3±8.9 mCi) of 89Zr was produced at 40 µA for 180 min (3 h) proton i...

This paper presents a novel approach, based on the standard addition method, for overcoming the matrix effects that often hamper the accurate characterization of nanoparticles (NPs) in complex samples via single particle inductively coupled plasma mass spectrometry (SP-ICP-MS). In this approach, calibration of the particle size is performed by two different methods: (i) by spiking a suspension of NPs standards of known size containing the analyte, or (ii) by spiking the sample with ionic standards; either way, the measured sensitivity is used in combination with the transport efficiency (TE) for sizing the NPs. Moreover, such transport efficiency can be readily obtained from the data obtained via both calibration methods mentioned above, so that the particle number concentration can also be determined. The addition of both ionic and NP standards can be performed on-line, by using a T-piece with two inlet lines of different dimensions. The smaller of the two is used for the standards, t...

Properly calibrated discrete dynode SEM ion-counting detectors and minimization of blank Os by an improved vial-cleaning method enables Os isotope analysis at the 1-15 pg level with high accuracy and precision....

Engineered nanomaterials are becoming increasingly ubiquitous in our society, with numerous applications in medicine, consumer products, bioremediation, and advanced materials. As these nanomaterials increase in variety, analyzing their characteristics is of great importance. Single particle inductively coupled plasma-mass spectrometry (SP-ICP-MS) is a high-throughput, sensitive, and robust instrumental analysis method used to simultaneously characterize and quantify nanoparticles in a variety of matrices. One such type of nanoparticle of interest is amorphous silica nanoparticles (SiNPs). SiNPs have widespread use in consumer products such as food and cosmetics and are prime candidates for novel medical applications and uses in environmental bioremediation. Despite their increased use, SiNPs have been shown to have toxicological properties in vitro and in vivo, particularly with regard to the immune system. Because of the potential for increased SiNP exposure in the general public and...

Lithium (Li) and Magnesium (Mg) isotopes have been widely used as valuable tracers to study geological processes. In general, several column separation procedures have been used to separate Li and Mg. In this study, we present an optimized protocol for the rapid and simultaneous purification of Li and Mg, which significantly reduces the separation time, required reagent volume, and procedural blanks compared to previous methods. Samples with small amounts of Li (generally 5 ng Li yielding Mg masses of 1-1200 μg) were separated, with the corresponding yields of Li and Mg being nearly 100%....

Recent studies, including many from the GEOTRACES program, have expanded our knowledge of trace metals in the Arctic Ocean, an isolated ocean dominated by continental shelf and riverine inputs. Here, we report a unique, pan-Arctic linear relationship between dissolved copper (Cu) and nickel (Ni) present north of 60°N that is absent in other oceans. The correlation is driven primarily by high Cu and Ni concentrations in the low salinity, river-influenced surface Arctic and low, homogeneous concentrations in Arctic deep waters, opposing their typical global distributions. Rivers are a major source of both metals, which is most evident within the central Arctic's Transpolar Drift. Local decoupling of the linear Cu-Ni relationship along the Chukchi Shelf and within the Canada Basin upper halocline reveals that Ni is additionally modified by biological cycling and shelf sediment processes, while Cu is mostly sourced from riverine inputs and influenced by mixing. This observation highlights...

. The values and distribution patterns of the strontium (Sr) isotope ratio 87Sr / 86Sr in Earth surface materials is of use in the geological, environmental and social sciences. Ultimately, the 87Sr / 86Sr ratio of soil and everything that lives in and on it is inherited from the rock that is its parent material. In Australia, there are few large-scale surveys of 87Sr / 86Sr available, and here we report on a new, low-density dataset using 112 catchment outlet (floodplain) sediment samples covering 529,000 km2 of inland southeastern Australia (South Australia, New South Wales, Victoria). The coarse (< 2 mm) fraction of bottom sediment samples (depth ~0.6-0.8 m) from the National Geochemical Survey of Australia were milled and fully digested before Sr separation by chromatography and 87Sr / 86Sr determination by multicollector-inductively coupled plasma-mass spectrometry. The results show a wide range of 87Sr / 86Sr values from a minimum of 0.7089 to a maximum of 0.7511 (range 0.0422...

A compact infrared-heated sample introduction system provides essentially 100% transport efficiency for single particle inductively coupled plasma mass spectrometry....

Anthropogenic increased atmospheric CO2 concentrations will lead to a drop of 0.4 units of seawater pH and ocean warming up to 4.8°C by 2100. Contaminant's toxicity is known to increase under a climate change scenario. Rare earth elements (REE) are emerging contaminants, that until now have no regulation regarding maximum concentration and discharge into the environment and have become vital to new technologies such as electric and hybrid-electric vehicle batteries, wind turbine generators and low-energy lighting. Studies of REE, namely Lanthanum (La) and Gadolinium (Gd), bioaccumulation, elimination, and toxicity in a multi-stressor environment (e.g., warming and acidification) are lacking. Hence, we investigated the algae phytoremediation capacity, the ecotoxicological responses and total chlorophyll and carotenoid contents in Ulva rigida during 7 days of co-exposure to La or Gd (15 µg L−1 or 10 µg L−1, respectively), and warming and acidification. Additionally, we assessed th...

Molybdenum is an essential dietary trace element required for several critical enzyme systems. High intake is associated with toxicity in ruminants and animal studies. The proposed therapeutic use of molybdenum based drugs poses a potential risk for accumulation through chronic administration of therapeutic doses of this element. The current experiment was designed to study the effect of daily dosing of a molybdenum compound, bis-choline tetrathiomolybdate (TTM), in Sprague Dawley rats using laser ablation inductively coupled plasma time-of-flight mass spectrometry (LA-ICP-ToF-MS), and two dosing levels of TTM for up to 3-months. To investigate if molybdenum accumulation was associated with tissue toxicity, histopathology, haematology and clinical biochemistry markers of toxicity were incorporated into the study design. There were no behavioural signs of toxicity to the rats, and no clinical or anatomic pathology associated with treatment. The current data did show a progressive accumu...

Due to an ever-increasing demand for commodity and technology metals, secondary resources can complement the primary resource supply. Sulfidic mining waste from the Neves-Corvo mine (Portugal) is a pyrite-rich tailing that still contains valuable metals (Cu, Zn) and minor amounts of technology metals (Co, Mn) in the form of sulfides. In this work, by fine-tuning a fast microwave (MW)-assisted oxidative roasting process (5 min, 550 °C), the sulfide minerals containing the desired metals converted to water-soluble sulfate phases, whereas pyrite converted to water-insoluble magnetite and hematite. The desired metals Cu (76%) and Zn (46%), as well as Co (66%) and Mn (53%), could thus be selectively leached over Fe (2.9%) in water (25 °C, 30 min). The obtained leachates were further purified by selectively precipitating Fe (95%) and As (100%) by a MW-assisted hydrothermal treatment (150 °C, 1 h), leaving Cu, Zn, Mn, and Co in solution for further recovery. In the proposed three-step meth...