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Rheumatoid arthritis (RA) is a chronic autoimmune disease featuring an abnormal immune microenvironment and resultant accumulation of hydrogen ions (H+) produced by activated osteoclasts (OCs). Currently, clinic RA therapy can hardly achieve sustained or efficient therapeutic outcomes due to the failures in generating sufficient immune modulation and manipulating the accumulation of H+ that deteriorates bone damage. Herein, a highly effective immune modulatory nanocatalytic platform, nanoceria‐loaded magnesium aluminum layered double hydroxide (LDH‐CeO2), is proposed for enhanced immune modulation based on acid neutralization and metal ion inherent bioactivity. Specifically, the mild alkaline LDH initiates significant M2 repolarization of macrophages triggered by the elevated antioxidation effect of CeO2 via neutralizing excessive H+ in RA microenvironment, thus resulting in the efficient recruitment of regulatory T cell (Treg) and suppressions on T helper 17 cell (Th 17) and plasma cells. Moreover, the osteogenic activity is stimulated by the Mg ion released from LDH, thereby promoting the damaged bone healing. The encouraging therapeutic outcomes in adjuvant‐induced RA model mice demonstrate the high feasibility of such a therapeutic concept, which provides a novel and efficient RA therapeutic modality by the immune modulatory and bone‐repairing effects of inorganic nanocatalytic material. [ABSTRACT FROM AUTHOR]

Tumor-associated bacteria (TAB) play a critically important role in regulating the microenvironment of a tumor, which consequently greatly deteriorates the therapeutic effects by chemo- and radiotherapy deactivation and, more considerably, leads to substantial immunosuppression. On the contrary, herein we propose a nanocatalytic tumor-immunotherapeutic modality based on the bacteria disintegration by bacteria-specific oxidative damage under magnetic hyperthermia for highly effective immune response activation-promoted tumor regression. A monodispersed and superparamagnetic nanocatalytic medicine modified by arginyl-glycyl-aspartic acid (RGD) and (3-carboxypropyl)triphenylphosphonium bromide (TPP), named as MNP-RGD-TPP herein, has been synthesized, which features selective accumulation at the TAB by the electrostatic affinity, enabling effective TAB disintegration by the nanocatalytic Fenton reaction producing abundant cytotoxic hydroxyl radicals in situ under alternating magnetic field-induced hyperthermia. More importantly, the lipopolysaccharide has been metabolically secreted from the destructed TAB as pathogen-associated molecular patterns (PAMPs) to M1-polarize tumor-associated macrophages (TAMs) and promote the maturation of dendritic cells (DCs) for innate immuno-response activation of TAMs, followed by cytotoxic T lymphocytes awakening under the PAMPs presentation by the mature DCs against tumor cells. The integrated innate and adaptive immunity activations based on this TAB-promoted nanocatalytic immunomedicine, instead of magnetic heating-induced hyperthermia or the released Fe2+/Fe3+ Fenton agent, has been found to achieve excellent therapeutic efficacy in an orthotopic colorectal cancer model, demonstrating the great potential of such an integrated immunity strategy in clinical tumor immunotherapy. [ABSTRACT FROM AUTHOR]

Abstract Eurasian permafrost serves as an important nitrogen source for linked aquatic and oceanic ecosystems. To fill in the data gaps in the southern margin of the Eurasian permafrost, nitrogen dynamics in the two rivers that drain the permafrost in the Great Xing'an Mountains of northeast China were investigated during the 2012–2015 growing seasons. The mean concentration of total dissolved nitrogen (TDN) in the two catchments was 0.63 mg L−1, which is generally higher than other permafrost catchments around the Arctic Ocean. The dissolved organic nitrogen (DON) constituted the majority of TDN, and the mean DON:TDN ratio was as high as 0.84. The seasonal flood patterns broadly influenced the concentrations and annual loads of DON, as well as the dissolved organic carbon (DOC):DON ratios in the two rivers. River discharge was positively related to DON concentration during growing seasons, while the concentrations of dissolved inorganic nitrogen (DIN), namely ammonium and nitrate, demonstrated no relationship with discharge. The estimated annual TDN yield, 190 kg km−2 yr−1 on average, was much higher than in the large Arctic rivers that drain permafrost. This yield accounts for 42.7% of the total atmospheric nitrogen deposition in the study area, which indicates a great potential for dissolved nitrogen export from the permafrost area in the Great Xing'an Mountains. Graphical abstract Unlabelled Image Highlights • N loads and yields are estimated in the south margin of Eurasian permafrost. • Mean TDN concentration is higher than other sites around the Arctic Ocean. • Annual TDN yield accounts for 42.7% of the total atmospheric N deposition. • Discharge pattern is the main controlling factor on DON concentrations. [ABSTRACT FROM AUTHOR]

Precise and effective initiation of the apoptotic mechanism in tumor cells is one of the most promising approaches for the treatment of solid tumors. However, current techniques such as high-temperature ablation or gene editing suffer from the risk of damage to adjacent normal tissues. This study proposes a magnetothermal-induced CRISPR-Cas9 gene editing system for the targeted knockout of HSP70 and BCL2 genes, thereby enhancing tumor cell apoptosis. The magnetothermal nanoparticulate platform is composed of superparamagnetic ZnCoFe2O4@ZnMnFe2O4 nanoparticles and the modified polyethyleneimine (PEI) and hyaluronic acid (HA) on the surface, on which plasmid DNA can be effectively loaded. Under the induction of a controllable alternating magnetic field, the mild magnetothermal effect (42℃) not only triggers dual-genome editing to disrupt the apoptosis resistance mechanism of tumor cells but also sensitizes tumor cells to apoptosis through the heat effect itself, achieving a synergistic therapeutic effect. This strategy can precisely regulate the activation of the CRISPR-Cas9 system for tumor cell apoptosis without inducing significant damage to healthy tissues, thus providing a new avenue for cancer treatment. [ABSTRACT FROM AUTHOR]

This study, conducted at the Emuer River in northern China during the growing season of 2014, investigated the concentrations and sources of dissolved CH 4 and CO 2 in wetland rivers in the permafrost region, as well as the total export of dissolved gaseous carbon (C) transported by streamflow. CH 4 and CO 2 concentrations in these rivers, ranging from 0.410–1.045 to 107.838–190.925 μmol L −1 , respectively, were among the highest levels of gaseous C concentrations reported from studies around the world. The concentrations of the C gases varied greatly with streamflow, but the influence of hydrological, as well as meteorological parameters, was not significant, except for the influence of the thaw depth of the soil active layer of adjacent wetlands on CH 4 concentrations. δ 18 O‰ values suggest the observed dissolved gases originated mainly from soil pore water in the active layers of the wetlands, as opposed to organic-rich sediments in river beds, which serves as a common source for riverine CH 4 and CO 2 according to many other studies. A total of 444.30 t C was exported by the 3rd order main Emuer river during the growing season, and an export coefficient of 4.65 mg C m −2 day −1 was calculated for the wetland ecosystem. The dataset in this study is significant with regard to the global carbon balance because it is representative of the extensive wetlands occurring throughout the Eurasian permafrost. [ABSTRACT FROM AUTHOR]

To quantify the fluxes and examine the controls on greenhouse gas emissions from the permafrost marshes where the fate of the large quantity of soil organic carbon remains poorly understood, we measured carbon dioxide (CO 2 ) and methane (CH 4 ) emissions in the northern region of the Great Xing'an Mountains, northeast China, in the thawing seasons of 2011 and 2012. The mean CO 2 and CH 4 fluxes from the marshes were estimated at 403.47 and 0.14 mg m −2 h −1 on average during the two years. Soil temperature was determined as the primary control on the seasonal greenhouse gas emissions during the growing period. The Q 10 values, calculated from the exponential regression between soil temperature and CO 2 emissions, suggest that the sensitivity of CO 2 flux to climate warming has a high spatially variability in the study area. Absorption of atmospheric CH 4 was seasonally detected at the sites with lower water table, which confirms the potential of the natural marshes as CH 4 sink when water table goes down due to climate change. When viewed from the ecosystem scale, the mean annual water table level and aboveground primary production were deemed as the dominant influencing factors for the mean annual fluxes, which suggests that there were different controls on the gas emissions at different spatial scales. Therefore, the primary controls of the CO 2 and CH 4 emissions at different spatial scales need to be surveyed in more detail when focusing on the future alteration of greenhouse gas emissions from permafrost marshes due to climate warming. [ABSTRACT FROM AUTHOR]

Data from four components of the radiation balance were used to investigate the surface energy budgets for a Carex lasiocarpa mire in the Sanjiang Plain, Northeast China, and the controlling factors of the evapotranspiration (ET) were discussed in detail. During the growing season 2006, the shortwave radiation ( SW↓) reaching the mire surface added up to 2,854.3 MJ m and the net radiation ( Rn) was 1,637.4 MJ m in total, with an average of 9.86 MJ m day. G was the smallest flux at the water-atmosphere interface, with an average of about 0.91 MJ m day, but showed high relative variability, even changing its sign. The latent and sensible heat fluxes (LE and H) amounted to 787.48 and 476.26 MJ m, respectively, and the total sum of LE and H accounted for 77.18% of Rn. By conversion from LE, the average value of ET from the mire was 1.84 mm day, amounting to 298.8 mm. The total ET was almost 60% of the total rainfall in the same period, proving that ET is the primary water consumer in the mire. The growth of C. lasiocarpa was related closely with surface resistance ( r), and analysis of partial correlation indicated that r correlated negatively with leaf area index (LAI) when the interference of the available energy, Rn- G, was removed. There was a strong linkage between r and the evaporative fraction [LE/(LE + H)] as well as Bowen ratio ( β). r was the key factor in controlling the variation of ET and regulating energy partitioning between LE and H. During the whole growing season, r and R− G were the two main factors coupled in ET processes. In spring, r dominated ET processes, and the increase in LAI led to a decrease in r, which in turn accelerated ET as vegetation developed until late August. After August, the available energy controlled the process of ET completely until ET reached an equilibrium in mid-October. [ABSTRACT FROM AUTHOR]

Global warming may have a great impact on soil organic carbon (SOC) turnover in permafrost peatlands. The response of microbial residues, as precursors of SOC, to climate warming remains unknown. A 6-year in situ warming experiment was conducted in the permafrost peatlands of Great Hing'an Mountains. Three commonly used amino sugars (glucosamine, GluN; galactosamine, GalN; muramic acid, MurA), for the quantification of microbial residues, were determined in two depths (0–15 cm, shallow soil; 15–30 cm, deep soil) of the bulk and rhizosphere soil of the shrub and Eriophorum vaginatum L. The amount of GluN, GalN, and MurA in deep shrub rhizosphere soil in the warming treatment decreased by 12.65%, 26.11%, and 14.78%, respectively, as compared to that in the control treatment. Yet, warming did not alter the amount of amino sugars in shallow and deep bulk soil. Warming decreased the concentrations of GluN, MurA, and total amino sugars in the deep rhizosphere soil of Eriophorum vaginatum L. by 22.04%, 26.14%, and 18.71%, respectively. Amino sugars in the deep rhizosphere soil of Eriophorum vaginatum L. had a higher temperature sensitivity than those in the deep bulk soil, while total amino sugars in the shallow rhizosphere soil of Eriophorum vaginatum L. had a lower temperature sensitivity than those in the deep rhizosphere soil. • Warming decreased deep rhizosphere soil amino sugars in permafrost peatlands. • Warming did not affect amino sugars in bulk soil. • Amino sugars contributed slightly to SOC in permafrost peatlands. [ABSTRACT FROM AUTHOR]

• Effect of wetland reclamation to paddy on energy balance and ET is evaluated. • ET energy consumption increases considerably due to wetland reclamation. • Main controlling factor of ET processes is altered after wetland reclamation. • Changes in hydrological environment and canopy features are main causation. Sustained, large-scale wetland reclamation of paddy fields has been implemented since the 1960s in the Sanjiang Plain, northeast China. The investigation of the effect of this reclamation on land-surface energy exchange and the local water cycle is important for evaluating the stability of regional water resources for future agriculture development and ecological conservation. This study used the eddy covariance method to measure evapotranspiration (ET) and dominant energy transport fluxes for two sites, a typical natural marsh and a paddy field, during the growing seasons of 2017–2018. The two sites showed similar total available energy, whereas the ratio of the latent to net radiative energy (LE / R n) was substantially lower in the marsh (0.49) compared to the paddy field (0.81), indicating a considerable increase in ET energy consumption after wetland reclamation. The average ET rates of the marsh and paddy field were 2.3 mm d−1 and 3.6 mm d−1, respectively, throughout the growing season. Both the high Priestley-Taylor coefficient (α eq , 1.21 ± 0.20) and the decoupling factor (Ω) suggested R n -limited conditions in the paddy field, whereas the controlling factor in the marsh changed from vapor pressure deficit (VPD) to radiation energy over the season. The greatest difference in ET occurred in spring due to the alteration in the hydrological environment, including a lowered standing water table and elevated water temperature in the paddy site. The differences in physiology and canopy shape between the paddy and marsh plants contributed largely to enhanced ET during the summer months. In total, alterations in the hydrological environment, canopy structure and plant physiology contributed to the increase in ET , suggesting a synthetic influence of marsh reclamation on surface energy and ET processes. Wetland reclamation increased water consumption through ET and altered the seasonal pattern of the energy balance. This process will inevitably result in increased deficits in regional water resources in the Sanjiang Plain. [ABSTRACT FROM AUTHOR]

Fenton reactions have been recently applied in tumor catalytic therapy, whose efficacy suffers from the unsatisfactory reaction kinetics of Fe3+ to Fe2+ conversion. Here we introduce a co‐catalytic concept in tumor catalytic therapy by using a two‐dimensional molybdenum disulfide (MoS2) nanosheet atomically dispersed with Fe species. The single‐atom Fe species act as active sites for triggering Fenton reactions, while the abundant sulfur vacancies generated on the nanosheet favor electron capture by hydrogen peroxide for promoting hydroxyl radical production. Moreover, the 2D MoS2 support also acts as a co‐catalyst to accelerate the conversion of Fe3+ to Fe2+ by the oxidation of active Mo4+ sites to Mo6+, thereby promoting the whole catalytic process. The 2D nanocatalyst exhibits a desirable catalytic performance, as well as a significantly enhanced anticancer efficacy both in vitro and in vivo, which indicates the feasibility for applying such a co‐catalytic concept in tumor therapy. [ABSTRACT FROM AUTHOR]

Fenton reactions have been recently applied in tumor catalytic therapy, whose efficacy suffers from the unsatisfactory reaction kinetics of Fe3+ to Fe2+ conversion. Here we introduce a co‐catalytic concept in tumor catalytic therapy by using a two‐dimensional molybdenum disulfide (MoS2) nanosheet atomically dispersed with Fe species. The single‐atom Fe species act as active sites for triggering Fenton reactions, while the abundant sulfur vacancies generated on the nanosheet favor electron capture by hydrogen peroxide for promoting hydroxyl radical production. Moreover, the 2D MoS2 support also acts as a co‐catalyst to accelerate the conversion of Fe3+ to Fe2+ by the oxidation of active Mo4+ sites to Mo6+, thereby promoting the whole catalytic process. The 2D nanocatalyst exhibits a desirable catalytic performance, as well as a significantly enhanced anticancer efficacy both in vitro and in vivo, which indicates the feasibility for applying such a co‐catalytic concept in tumor therapy. [ABSTRACT FROM AUTHOR]

Nanocatalytic tumor therapy based on Fenton nanocatalysts has attracted considerable attention because of its therapeutic specificity, enhanced outcomes, and high biocompatibility. Nevertheless, the rate‐determining step in Fenton chemistry, which involves the transition of a high‐valence metallic center (FeIII) to a Fenton‐active low‐valence metallic center (FeII), has hindered advances in nanocatalyst‐based therapeutics. In this study, we constructed mesoporous single iron atomic nanocatalysts (mSAFe NCs) by employing catechols from dopamine to coordinate and isolate single iron atoms. The catechols also serve as reductive ligands, generating a field‐effect‐based cocatalytic system that instantly reduces FeIII species to FeII species within the mSAFe NCs. This self‐motivated cocatalytic strategy enabled by mSAFe NCs accelerates the kinetics of the Fenton catalytic reaction, resulting in remarkable performance for nanocatalytic tumor therapy both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Nanocatalytic tumor therapy based on Fenton nanocatalysts has attracted considerable attention because of its therapeutic specificity, enhanced outcomes, and high biocompatibility. Nevertheless, the rate‐determining step in Fenton chemistry, which involves the transition of a high‐valence metallic center (FeIII) to a Fenton‐active low‐valence metallic center (FeII), has hindered advances in nanocatalyst‐based therapeutics. In this study, we constructed mesoporous single iron atomic nanocatalysts (mSAFe NCs) by employing catechols from dopamine to coordinate and isolate single iron atoms. The catechols also serve as reductive ligands, generating a field‐effect‐based cocatalytic system that instantly reduces FeIII species to FeII species within the mSAFe NCs. This self‐motivated cocatalytic strategy enabled by mSAFe NCs accelerates the kinetics of the Fenton catalytic reaction, resulting in remarkable performance for nanocatalytic tumor therapy both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Immunogenic cell death (ICD) based on endoplasmic reticulum (ER) stress has been widely studied as the fundamentals of cancer immunotherapy. However, the currently available ICD inducers are still very rare and mostly highly toxic chemotherapeutic drugs. Herein, a novel ICD modality based on mitochondrial heat stress by magnetic hyperthermia treatment (MHT), is proposed for effectively evoking tumor-associated macrophages (TAMs) against cancer cells. A monodisperse and biocompatible nanomedicine by grafting arginyl-glycyl-aspartic acid (RGD) and (3-carboxypropyl)triphenylphosphonium bromide (TPP) onto the surface of superparamagnetic ZnCoFe 2 O 4 @ZnMnFe 2 O 4 nanoparticles (MNPs), named as MNPs-RGD-TPP (MRT), was synthesized for mitochondrial heat stress-induced oxidative damage of tumor cells under the magnetothermal manipulation. Such heat stress-damaged mitochondria can cause the immunogenic death of tumor cells to release damage-associated molecular patterns (DAMPs), including ATP and HSP 70, to M1-polarize TAMs, resulting in the reactivated immunoresponse of macrophages against cancer cells. The effectiveness and robustness of MRT nanomedicine in evoking TAMs-mediated extracellular killing or phagocytosis are verified both in vitro and in vivo. Such a therapeutic approach based on mitochondria-targeted magnetothermal ICD for activating TAMs may be instructive to future anticancer immunotherapy. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Peatlands are the significant source of atmospheric methane (CH4), which is produced during peat accumulation. In this study, we investigated CH4 emissions over two growing seasons from a Carex lasiocarpa-dominated peatland in the Sanjiang Plain in China using the static chamber technique. We also investigated the environmental factors controlling emissions during the two years of study, 2012 and 2013. CH4 emissions ranged from 0.07 to 56.01 mg CH4–C m−2 h−1 with mean values of 7.33 ± 1.65 mg C m−2 h−1, showing significant temporal patterns in both years with peak values in early June and middle August respectively. Variations in water table, soil temperature at 25 cm depth and soil's water-filled pore space together explained 66.7% of the observed temporal variation of CH4 fluxes by the step-wise regression. Rapid and short-lived precipitation events might have no immediate influence on CH4 emissions, which primarily depended on the actual soil aeration and moisture conditions. A simple relationship between single parameter and CH4 fluxes would be overruled once the water table dropped below the critical threshold for CH4 release. The amount of CH4 emitted from the herbaceous peatland in the Sanjiang Plain during the growing season was about 6.93 × 1012 mg C. Our results suggested that the herbaceous peatland in the Sanjiang Plain is an important source of atmospheric CH4. [Copyright &y& Elsevier]

Abstract: Plants play an important role in CH4 emissions from wetlands. Vascular plants transport CH4 from the anaerobic zone to the atmosphere through their aerenchyma, thereby bypassing the aerobic zone and strongly increasing CH4 emission rates. However, most studies of the effect of plants on wetland CH4 emissions are based on observations made during the growing seasons. The effects in non-growing seasons are still unclear. In this study, we conducted a clipping experiment to investigate the effects of plants on CH4 emissions from a temperate marsh in the growing and non-growing seasons. The results show that the influence of plants on CH4 emissions from the wetland varied among different seasons. Plant-mediated CH4 accounted for 38% of the total fluxes in the plant-growing season. After the growing season, whether the plants transported CH4 from the soil to the atmosphere in situ was determined by the involved environmental conditions. In autumn, the plants did not transport CH4. This is because the CH4 diffused easily in the soil and water, rather than via the plants'' organs. In the surface soil freezing period, CH4 diffusion was blocked and accumulated under the frozen surface. The highly concentrated CH4 in the pore water was compelled to enter the organs of the plants and diffused by them. The ‘passive diffusion’ via plants transported 84% of the total CH4 emissions during this period. Nonetheless, the plants did not transport CH4 again in the deep soil freezing season. By synthesizing our data together with previous studies, we suggested that this is because the frozen soil layer was deep enough in this period to exceed the depth horizon of the plants'' roots and the CH4 in free water could not enter the plants'' organs. [Copyright &y& Elsevier]

Understanding the shifts in competitive ability and its driving forces is key to predict the future of plant invasion. Changes in the competition environment and soil biota are two selective forces that impose remarkable influences on competitive ability. By far, evidence of the interactive effects of competition environment and soil biota on competitive ability of invasive species is rare. Here, we investigated their interactive effects using an invasive perennial vine, Mikania micrantha. The competitive performance of seven M. micrantha populations varying in their conspecific and heterospecific abundance were monitored in a greenhouse experiment, by manipulating soil biota (live and sterilized) and competition conditions (competition‐free, intraspecific, and interspecific competition). Our results showed that with increasing conspecific abundance and decreasing heterospecific abundance, (1) M. micrantha increased intraspecific competition tolerance and intra‐ vs. interspecific competitive ability but decreased interspecific competition tolerance; (2) M. micrantha increased tolerance of the negative soil biota effect; and (3) interspecific competition tolerance of M. micrantha was increasingly suppressed by the presence of soil biota, but intraspecific competition tolerance was less affected. These results highlight the importance of the soil biota effect on the evolution of competitive ability during the invasion process. To better control M. micrantha invasion, our results imply that introduction of competition‐tolerant native plants that align with conservation priorities may be effective where M. micrantha populations are long‐established and inferior in inter‐ vs. intraspecific competitive ability, whereas eradication may be effective where populations are newly invaded and fast‐growing. [ABSTRACT FROM AUTHOR]

Surgical intervention followed by chemotherapy is the principal treatment strategy for bladder cancer, which is hindered by significant surgical risks, toxicity from chemotherapy, and high rates of recurrence after surgery. In this context, a novel approach using mild magnetic hyperthermia therapy (MHT) for bladder cancer treatment through the intra-bladder delivery of magnetic nanoparticles is presented for the first time. This method overcomes the limitations of low magnetic thermal efficiency, inadequate tumor targeting, and reduced therapeutic effectiveness associated with the traditional intravenous administration of magnetic nanoparticles. Core-shell Zn–CoFe 2 O 4 @Zn–MnFe 2 O 4 (MNP) nanoparticles were developed and further modified with hyaluronic acid (HA) to enhance their targeting ability toward tumor cells. The application of controlled mild MHT using MNP-HA at temperatures of 43–44 °C successfully suppressed the proliferation of bladder tumor cells and tumor growth, while also decreasing the expression levels of heat shock protein 70 (HSP70). Crucially, this therapeutic approach also activated the body's innate immune response involving macrophages, as well as the adaptive immune responses of dendritic cells (DCs) and T cells, thereby reversing the immunosuppressive environment of the bladder tumor and effectively reducing tumor recurrence. This study uncovers the potential immune-activating mechanism of mild MHT in the treatment of bladder cancer and confirms the effectiveness and safety of this strategy, indicating its promising potential for the clinical management of bladder cancer with a high tendency for relapse. [Display omitted] [ABSTRACT FROM AUTHOR]

2D monoelemental nanomaterials (Xenes) have shown tremendous potential for versatile biomedical applications. Bismuth, as a heavy element in pnictogens, has acquired massive research interest due to its unique optical performance, high biocompatibility, stability, and relatively low cost. However, the utilization of 2D bismuthene in nanomedicine has not been achieved because of the difficulty in engineering bismuthene with crucial structural/compositional characteristics for satisfying strict biomedical requirements. Herein, to address this Gordian knot, a facile strategy to intercalate and delaminate Bi bulk for generating mass few‐layered 2D bismuthene with high yield by employing a water molecule mediated freezing–thawing process and sodium borohydride‐triggered reduction treatment is proposed. The resulting 2D bismuthene displays good optical performance in the near‐infrared (NIR) biowindow and can be excited via red light for reactive oxygen species generation, enabling applications in multiple photonic cancer nanomedicine settings, including photothermal hyperthermia and photodynamic therapy. Utilizing the intrinsic desirable optical absorbance and strong X‐ray attenuation of bismuthene, dual photonic therapy can be conducted under the supervision of photoacoustic/computed tomography guided multimodal imaging. This research not only offers a potential mass‐production ready, cost‐effective, and eco‐efficient methodology for engineering 2D Xenes, but also exploits an innovative 2D bismuthene based photonic cancer nanomedicine. [ABSTRACT FROM AUTHOR]

Abstract Influences of climatic change and anthropogenic activities on the terrestrial water storage (TWS) change are significant in the mid- and high-latitude areas. Since 2002, the Gravity Recovery and Climate Experiment (GRACE) satellite mission has provided quantitative measurements of TWS changes with unprecedented accuracy at global, regional and basin scales. In this study, the noise level of various GRACE-derived TWS anomalies (TWSA) data were evaluated by using a generalized three-cornered hat (GTCH) method. A time-dependent weights approach was adopted to obtain a combined TWSA series over the Songhua River Basin (SRB) from 2003 to 2013. Monthly TWSA data during the past decades (1982–2002) were reconstructed by using an artificial neural network (ANN) approach with the good performance evaluated by the correlation coefficient of 0.89 and the Nash-Sutcliff efficiency of 0.79 over the study region. In-situ groundwater level measurements were used for validation of the groundwater storage (GWS) changes (estimated by using GRACE-derived TWS changes in association with the other simulated components of water storage changes from land surface models (LSMs)). The primary driving factors of spatiotemporal variations of GWS, as well as their inter-/intra-annually varying characteristics, were explored. The present study revealed that the variations of GWS featured a "downward fluctuations" (1982–1994), "stable upward" (1998–2008) and "decreasing dramatically" (2009–2013) period, respectively, over the SRB. In general, GWS had varied in a steady decline trend at a decreasing rate of 1.04 ± 0.59 mm year−1 from 1982 to 1994. With the enhanced climatic and anthropogenic influences over the region since 2000, several severe fluctuations characterized the GWS variations with occurrences of spring droughts and flooding over the region, which suggested significant effects of global changes posed on GWS variations of the region. Graphical abstract Unlabelled Image Highlights • Several GRACE solutions were evaluated and combined. • Longer-term groundwater storage variations were hindcasted by using the ANN model. • Long-term spatial-temporal variations of groundwater storage were analyzed. • The dominant driving factors for groundwater storage changes were explored. [ABSTRACT FROM AUTHOR]

Freeze-thaw (FT) events and increasing nitrogen (N) availability may alter N turnover and nitrous oxide (N 2 O) emissions in permafrost peatlands. However, the responses of N 2 O emissions to different N levels and additions during FT events are far from clear. We conducted an incubation study to investigate the impacts of different N addition levels (LN: 0.07 mg N g −1 , HN: 0.14 mg N g −1 ) and N addition forms (AC: ammonium chloride, NS: sodium nitrate) on the emissions of N 2 O under FT and non-freeze-thaw (NFT) conditions in boreal peatlands of Northeast China. Results indicated that the FT condition significantly increased N 2 O emissions compared with the NFT condition and peaks occurred during thawing. Compared with AC treatments, NS treatments significantly elevated the accumulation of N 2 O emissions under the FT condition, exhibiting significant differences in different NS levels. N 2 O emissions were also positively dependent on soil NO 3 − concentrations to supply nitrate for denitrification. Nitrate-N addition was mainly responsible for the burst of N 2 O with denitrification as the main process during FT events. Therefore, these results suggest that N 2 O emissions potentially increase during FT events with increasing nitrate-N deposition in permafrost peatlands, which would contribute to global climate warming. [ABSTRACT FROM AUTHOR]

Water level is important in determining plant zonation distribution patterns in freshwater wetlands. However, the role of whole-plants’ morphological traits in response to water level gradients in accounting for the distribution of marsh species is far from clear. Four typical dominant vascular plants with different distribution patterns (high-elevation species Deyeuxia angustifolia , mid-elevation species Carex lasiocarpa and Glyceria spiculosa , and low-elevation species Carex pseudocuraica ) in freshwater marshes in the Sanjiang Plain of Northeast China were treated with four static water level conditions (−5, 0, +5, and +15 cm relative to the soil surface), and each plant’s growth characteristics, biomass allocation and root traits were investigated. With the rising water level, the growth of D. angustifolia performed worse than other species, whereas the total biomass, plant height and relative growth rate (RGR) of C. pseudocuraica increased steadily. Compared with the other three species, C. pseudocuraica showed a distinct pattern with increasing water levels in the biomass allocation to photosynthetic and non-photosynthetic organs, as well as for coarse and fine roots. Flooding stress significantly reduced root diameter and C/N ratio but simultaneously increased the specific root length (SRL), specific root area (SRA) and root nitrogen concentration (RNC) for both coarse roots (1st order, >0.2 mm) and fine roots (2nd and 3rd orders, <0.2 mm). However, these root parameters of C. pseudocuraica exhibited an opposite response with the increase in the water level between such two different branching orders. Our results indicate that wetland plants could acclimate to flooding stress through resource trade-off among different tissues and trait-coordinated variation within the root system. Furthermore, species-specific shifts in above- and below-ground traits could help to better understand and predict the vegetation zonation patterns in temperate freshwater wetlands. [ABSTRACT FROM AUTHOR]

Northern peatlands contain a considerable share of the terrestrial carbon pool, which will be affected by future climatic variability. Using the static chamber technique, we investigated ecosystem respiration and soil respiration over two growing seasons (2012 and 2013) in a Carex lasiocarpa -dominated peatland in the Sanjiang Plain in China. We synchronously monitored the environmental factors controlling CO 2 fluxes. Ecosystem respiration during these two growing seasons ranged from 33.3 to 506.7 mg CO 2 –C m −2 h −1 . Through step-wise regression, variations in soil temperature at 10 cm depth alone explained 73.7% of the observed variance in log 10 (ER). The mean Q 10 values ranged from 2.1 to 2.9 depending on the choice of depth where soil temperature was measured. The Q 10 value at the 10 cm depth (2.9) appears to be a good representation for herbaceous peatland in the Sanjiang Plain when applying field-estimation based Q 10 values to current terrestrial ecosystem models due to the most optimized regression coefficient (63.2%). Soil respiration amounted to 57% of ecosystem respiration and played a major role in peatland carbon balance in our study. Emphasis on ecosystem respiration from temperate peatlands in the Sanjiang Plain will improve our basic understanding of carbon exchange between peatland ecosystem and the atmosphere. [ABSTRACT FROM AUTHOR]

[Display omitted] • Gold and silver encapsulated by silicates and Fe-oxide are pretreated with NH 4 HF 2. • NH 4 HF 2 pretreatment achieved under acidic conditions at low temperatures. • The leaching efficiency of gold and silver reached 97.6% and 94.8%, respectively. • The pretreatment process depended on the diffusion. • SiO 2 and Fe 2 O 3 were converted to SiF 6 2− and FeF2+, respectively. The secondary encapsulation of gold and silver by silicates and Fe-oxide during the roasting oxidation of refractory gold concentrate significantly influence the gold and silver leaching efficiency. In this study, a pretreatment method of refractory gold concentrate calcine using ammonium bifluoride and sulfuric acid solution is proposed. The effects of the NH 4 HF 2 and H 2 SO 4 concentration, pretreatment temperature, and time on the leaching efficiency of gold and silver were investigated in detail. The optimum conditions were determined to be NH 4 HF 2 concentration of 1.5 mol/L, H 2 SO 4 concentration of 2 mol/L, pretreatment temperature of 40°C, and duration of 90 min. The leaching efficiency of gold and silver reached 97.6 % and 94.8 %, respectively. The pretreatment process of refractory gold concentrate calcine can be expressed with Johnson-Mehl-Avrami (JMA) equation and depends on the diffusion. The pretreated residue was mainly composed of silicates and Fe-oxide minerals. The gold and silver can be exposed to the ore surface by NH 4 HF 2 pretreatment, which helps to improve its cyanide leaching efficiency. [ABSTRACT FROM AUTHOR]

Abstract: Natural wetlands play an important role in the global carbon cycle, and loss of dissolved carbon through water has been indicated as one of the most important carbon sources for riverine ecosystems. During the last century, a large natural wetland area was reported to be converted to other land use types such as rice paddy land around the world. In this study, we explored the dynamics of dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) in two natural freshwater wetlands and a rice paddy field, which was reclaimed from the natural wetlands in the Sanjiang Plain, Northeastern China, during the growing season (May–October) of 2009. The DOC and DIC concentrations in the two ecosystems were significantly different (P <0.05). The mean DOC concentrations during the growing season in the surface water of the Deyeuxia angustifolia and Carex lasiocarpa wetlands were 49.88±5.44 and 27.97±1.69mg/L, respectively, while it was only 8.63±2.54mg/L in the rice paddy field. Specific ultra-violet light absorption at 254nm (SUVA254) of DOC increased by an average of 19.54% in the surface water from the natural wetlands to rice paddy, suggesting that DOC mobilized in the natural wetlands was more aromatic than that in the rice paddy field. The mean DIC concentration in surface water of the rice paddy was 5.25 and 5.04 times higher than that in the natural D. angustifolia and C. lasiocarpa wetlands, respectively. The average ratio of DIC to dissolved total carbon (DTC) for the water sampled from the artificial drainage ditch in the rice paddy field was 61.82%, while it was 14.75% from the nearby channel of natural wetlands. The significant differences in dissolved carbon concentration in surface water and channels originating from different land use types suggested that reclamation of natural wetlands to rice paddy field would reduce DOC runoff and increase the DIC concentration to adjacent watersheds. Our study results for the changed pattern in dissolved carbon after the natural wetland was transformed to paddy field could have important implications for studying the impacts of the large-scale land use change to carbon cycle and management. [Copyright &y& Elsevier]

The net ecosystem CO2 exchange (NEE) is a critical parameter for quantifying terrestrial ecosystems and their contributions to the ongoing climate change. The accumulation of ecological data is calling for more advanced quantitative approaches for assisting NEE prediction. In this study, we applied two widely used machine learning algorithms, Random Forest (RF) and Extreme Gradient Boosting (XGBoost), to build models for simulating NEE in major biomes based on the FLUXNET dataset. Both models accurately predicted NEE in all biomes, while XGBoost had higher computational efficiency (6~62 times faster than RF). Among environmental variables, net solar radiation, soil water content, and soil temperature are the most important variables, while precipitation and wind speed are less important variables in simulating temporal variations of site-level NEE as shown by both models. Both models perform consistently well for extreme climate conditions. Extreme heat and dryness led to much worse model performance in grassland (extreme heat: R2 = 0.66~0.71, normal: R2 = 0.78~0.81; extreme dryness: R2 = 0.14~0.30, normal: R2 = 0.54~0.55), but the impact on forest is less (extreme heat: R2 = 0.50~0.78, normal: R2 = 0.59~0.87; extreme dryness: R2 = 0.86~0.90, normal: R2 = 0.81~0.85). Extreme wet condition did not change model performance in forest ecosystems (with R2 changing −0.03~0.03 compared with normal) but led to substantial reduction in model performance in cropland (with R2 decreasing 0.20~0.27 compared with normal). Extreme cold condition did not lead to much changes in model performance in forest and woody savannas (with R2 decreasing 0.01~0.08 and 0.09 compared with normal, respectively). Our study showed that both models need training samples at daily timesteps of >2.5 years to reach a good model performance and >5.4 years of daily samples to reach an optimal model performance. In summary, both RF and XGBoost are applicable machine learning algorithms for predicting ecosystem NEE, and XGBoost algorithm is more feasible than RF in terms of accuracy and efficiency. [ABSTRACT FROM AUTHOR]

Permafrost play an important role in regulating global climate system. We analyzed the gross primary productivity (GPP), net primary productivity (NPP), and evapotranspiration (ET) derived from MODIS and three earth system models participated in the Coupled Model Inter-comparison Project Phase 6 (CMIP6) in the Asian permafrost region. The water use efficiency (WUE) was further computed. The simulated GPP, NPP, and ET show slightly increasing trends during historical period (1900–2014) and strong increasing trends in projection period (2015–2100), and projected impacts of climate change on all variables are greater under high-emission scenarios than low-emission scenarios. Further analysis revealed higher increases in GPP and NPP than that of ET, indicating that vegetation carbon sequestration governs the growing WUE under historical and projected periods in this region. The GPP, NPP and ET showed higher changing rates in western, central and southeast areas of this region, and WUE (WUE GPP , and WUE NPP) shows the similar spatial pattern. Compared to MODIS-derived GPP, NPP, and ET during 2000–2014, Earth system models yield the best estimates for NPP, while slight underestimations for GPP and ET, and thus slight overestimations for WUE GPP and WUE NPP. This study highlights the predominant role of vegetation activity in regulating regional WUE in Asian permafrost region under future climate change. Vegetation domination of the growing water use efficiency implies that the permafrost region may continue acting efficiently in sequestrating atmospheric carbon in terms of water consumption throughout the 21st century. Unlabelled Image • Rising vegetation activity dominates the climbing water use efficiency in the Asian permafrost region from 1900 to 2100. • Large spatial heterogeneities in water and carbon fluxes were observed in the study domain. • The CMIP6 models projected substantial increases in GPP and NPP while slight increase in evapotranspiration during 2010-2100. [ABSTRACT FROM AUTHOR]