Ecological responses to hydrological connectivity in grassland riparian zones: Insights from vegetation and ground-dwelling arthropods.

Riparian wetlands have suffered from degradation due to global climate change and human activities, which can alter flora and fauna community patterns and disrupt material cycles in the riparian zones. Hydrological connectivity identified by functional and structural connectivity is an important driving force of riparian ecosystems. However, the role of hydrological connectivity in linking riparian hydrology and ecology remains unclear, especially in dryland rivers. By taking the riparian zone of the Xilin River in Eurasian steppe as an example, the functional connectivity was represented by the groundwater depth in the riparian zones. The structural connectivity was quantified by integrating the soil, and vegetation properties of the riparian zone. The structural connectivity decreased from upstream to downstream. Laterally, the highest structural connectivity was found in the riparian zone 25 m away from the river channel. The abundance of three groups of ground-dwelling arthropods (except Araneae) showed a threshold behavior in response to the functional connectivity, with the highest abundance occurring in the medium level of functional connectivity. Both vegetation biomass and ground-dwelling arthropod abundance were significantly and positively correlated to the structural connectivity strength. The results of structural equation models (SEMs) also indicated that structural connectivity was a key factor affecting vegetation and ground-dwelling arthropod abundance. The results underscore the essential function of hydrological connectivity in maintaining the biodiversity in the riparian zones. The study provides a scientific reference of riparian-zone restoration based on hydrological connectivity.

Storage and dynamics of soil organic carbon in allochthonous-dominated and nitrogen-limited natural and planted mangrove forests in southern Thailand.

Mangrove forests can help to mitigate climate change by storing a significant amount of carbon (C) in soils. Planted mangrove forests have been established to combat anthropogenic threats posed by climate change. However, the efficiency of planted forests in terms of soil organic carbon (SOC) storage and dynamics relative to that of natural forests is unclear. We assessed SOC and nutrient storage, SOC sources and drivers in a natural and a planted forest in southern Thailand. Although the planted forest stored more C and nutrients than the natural forest, the early-stage planted forest was not a strong sink relative to mudflat. Both forests were predominated by allochthonous organic C and nitrogen limited, with total nitrogen being a major driver of SOC in both cases. SOC showed a significant decline along land-to-sea and depth gradients as a result of soil texture, nutrient availability, and pH in the natural forest.

Shifted sediment-transport regimes by climate change and amplified hydrological variability in cryosphere-fed rivers.

Climate change affects cryosphere-fed rivers and alters seasonal sediment dynamics, affecting cyclical fluvial material supply and year-round water-food-energy provisions to downstream communities. Here, we demonstrate seasonal sediment-transport regime shifts from the 1960s to 2000s in four cryosphere-fed rivers characterized by glacial, nival, pluvial, and mixed regimes, respectively. Spring sees a shift toward pluvial-dominated sediment transport due to less snowmelt and more erosive rainfall. Summer is characterized by intensified glacier meltwater pulses and pluvial events that exceptionally increase sediment fluxes. Our study highlights that the increases in hydroclimatic extremes and cryosphere degradation lead to amplified variability in fluvial fluxes and higher summer sediment peaks, which can threaten downstream river infrastructure safety and ecosystems and worsen glacial/pluvial floods. We further offer a monthly-scale sediment-availability-transport model that can reproduce such regime shifts and thus help facilitate sustainable reservoir operation and river management in wider cryospheric regions under future climate and hydrological change.

Significant methane ebullition from large shallow eutrophic lakes of the semi-arid region of northern China.

Eutrophic lakes are a major source of the atmospheric greenhouse gas methane (CH4), and CH4 ebullition emissions from inland lakes have important implications for the carbon cycle. However, the spatio-temporal heterogeneity of CH4 ebullition emission and its influencing factors in shallow eutrophic lakes of arid and semi-arid regions remain unclear. This study aimed to determine the mechanism of CH4 emission via eutrophication in Lake Ulansuhai, a large shallow eutrophic lake in a semi-arid region of China.To this end, monthly field surveys were conducted from May to October 2021, and gas chromatography was applied using the headspace equilibrium technique with an inverted funnel arrangement. The total CH4 fluxes ranged from 0.102 mmol m-2 d-1 to 59.296 mmol m-2 d-1 with an average value of 4.984 ± 1.82 mmol m-2 d-1. CH4 ebullition emissions showed significant temporal and spatial variations. The highest CH4 ebullition emission was observed in July with a grand mean of 9.299 mmol m-2 d-1, and the lowest CH4 ebullition emissions occurred in October with an average of 0.235 mmol m-2 d-1. Among seven sites (S1-S7), the maximum (3.657 mmol m-2 d-1) and minimum (1.297 mmol m-2 d-1). CH4 ebullition emissions were observed at S2 and S7, respectively. As the main route of CH4 emission to the atmosphere in Lake Ulansuhai, the CH4 ebullition flux during May to October accounted for 69% of the total CH4 flux. Statistical analysis showed that CH4 ebullition was positively correlated with temperature (R = 0.391, P < 0.01) and negatively correlated with air pressure (R = 0.286, P < 0.00). Temperature and air pressure were found to strongly regulate the production and oxidation of CH4. Moreover, nutritional status indicators such as TP and NH4+-N significantly affect CH4 ebullition emissions (R = 0.232, P < 0.01; R = -0.241, P < 0.01). This study reveals the influencing factors of CH4 ebullition emission in Lake Ulansuhai, and provides theoretical reference and data support for carbon emission from eutrophic lakes. Nevertheless, research on eutrophic shallow lakes needs to be further strengthened. Future research should incorporate improved flux measurement techniques with process-based models to improve the accuracy from regional to large-scale estimation of CH4 emissions and clarify the carbon budget of aquatic ecosystems. In this manner, the understanding and predictability of CH4 ebullition emission from shallow lakes can be improved.

Fluxes in CO2 and CH4 and influencing factors at the sediment-water interface in a eutrophic saline lake.

Although saline aquatic ecosystems are significant emitters of greenhouse gases (GHGs), dynamic changes in GHGs at the sediment-water interface remain unclear. The present investigation carried out a total of four sampling campaigns in Daihai Lake, which is a eutrophic saline lake situated in a semi-arid area of northern China. The aim of this study was to investigate the spatio-temporal dynamics of carbon dioxide (CO2) and methane (CH4) fluxes at the sediment-water interface and the influencing factors. The mean concentrations of porewater CO2 and CH4 were 44.98 ± 117.99 µmol L-1 and 124.36 ± 97.00 µmol L-1, far exceeding those in water column of 11.14 ± 2.16 µmol L-1 and 0.33 ± 0.23 µmol L-1, respectively. The CO2 and CH4 fluxes at the sediment-water interface (FS-WCO2 and FS-WCH4) exhibited significant spatial and temporal variations, with mean values of 9.24 ± 13.84 µmol m-2 d-1 and 3.53 ± 4.36 µmol m-2 d-1, respectively, indicating that sediment is the source of CO2 and CH4 in the water column. However, CO2 and CH4 fluxes were much lower than those measured at the water-air interface in a companion study (17.54 ± 14.54 mmol m-2d-1 and 0.50 ± 0.50 mmol m-2d-1, respectively), indicating that the diffusive flux of gases at the sediment-water interface was not the primary source of CO2 and CH4 emissions to the atmosphere. Regression and correlation analyses revealed that salinity (Sal) and nutrients were the most influential factors on porewater gas concentrations, and that gas fluxes increased with increasing gas concentrations and porosity. The microbial activity of sediment is greatly affected by nutrients and Sal. Additionally, Sal has the ability to regulate biogeochemical processes, thereby regulating GHG emissions. The present investigation addresses the research gap concerning GHG emissions from sediments of eutrophic saline lakes. The study suggests that controlling the eutrophication and salinization of lakes could be a viable strategy for reducing carbon emissions from lakes. However, further investigations are required to establish more conclusive results.

Water and heat exchange responses to flooding and local storm events in the hyporheic zone driven by a meandering bend.

The hyporheic zone, i.e. the groundwater-surface water interface within riverine/riparian ecosystems, plays a key role in water transport, energy flow and biogeochemical cycling at watershed scales. Water and heat exchange are fundamental processes regulating biogeochemical cycles in the hyporheic zones. To improve the understanding of hyporheic flow and heat transport in meandering streams, high-resolution measurements of water level and temperature, combined with a 3-D coupled model of flow and heat transport in the hyporheic zone of a meandering bend, were carried out during a summer flood season. Results show the distinct spatio-temporal variations of hyporheic water and heat exchange. Flooding events (the incoming flood water generated by the upstream rainfall) and local rainstorm events (the storm or rainfall occurring over the local study area) are major drivers for the coupled processes. Incoming flooding from the upper stream increases the hyporheic water and heat exchange in the riverbed and inner bank leading to the longer intra-meander residence times, and warms the riverbed and riverbanks due to the post-rainfall thermal recovery. Local rainstorm event increases hyporheic water and heat exchange flux both laterally and vertically and cools down the riverbed and riverbanks. The water exchange and thermal regimes in the intra-meander seems more driven by the local exchange flows, while the counterparts in the outer bank are dominated by the regional groundwater flow. The temperatures in the inner banks are 1 to 3 °C higher than those in the outer banks, indicating the better hydrological connectivity between river water and groundwater in the intra-meander. The meander apex is a hot spot for hyporheic water and heat exchange. The results highlight the close coupling among river morphology, hyporheic flow, and thermal heterogeneity in a meander system.

Multicenter Evaluation of the Cepheid Xpert GBS LB XC Test.

Early-onset neonatal sepsis due to Streptococcus agalactiae (group B Streptococcus [GBS]) infection is one of the leading causes of newborn mortality and morbidity. The latest guidelines published in 2019 recommended universal screening of GBS colonization among all pregnant women and intrapartum antibiotic prophylaxis for positive GBS. The updated procedures allow rapid molecular-based GBS screening using nutrient broth-enriched rectovaginal samples. Commercially available molecular assays for GBS diagnosis target mainly the cfb gene, which encodes a hemolysin protein responsible for producing the Christie-Atkins-Munch-Petersen (CAMP) factor. cfb is considered a conserved gene in essentially all GBS isolates. However, false-negative GBS results on Cepheid Xpert GBS and GBS LB tests due to deletions in or near the region that encodes cfb were reported recently. Therefore, the new Xpert GBS LB XC test was developed. This study is a multicenter evaluation of the new test for GBS identification from nutrient broth-enriched rectal/vaginal samples from antepartum women. A total of 621 samples were prospectively enrolled. The samples were tested with the Xpert GBS LB XC test, the composite comparator method, which included the Hologic Panther Fusion GBS test combined with bacterial culture, followed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) identification, and bacterial culture alone, followed by MALDI-TOF MS identification. The respective sensitivity and specificity of the Xpert GBS LB XC test were 99.3% and 98.7% compared to the composite comparator method and 99.1% and 91.8% compared to bacterial culture alone with MALDI-TOF MS identification. Overall, the Xpert GBS LB XC test performed comparatively to the composite comparator method and is equivalent to traditional bacterial culture followed by MALDI-TOF MS.

Drivers of spatial and seasonal variations of CO2 and CH4 fluxes at the sediment water interface in a shallow eutrophic lake.

Shallow eutrophic lakes contribute disproportional to the emissions of CO2 and CH4 from inland waters. The processes that contribute to these fluxes, their environmental controls, and anthropogenic influences, however, are poorly constrained. Here, we studied the spatial variability and seasonal dynamics of CO2 and CH4 fluxes across the sediment-water interface, and their relationships to porewater nutrient concentrations in Lake Ulansuhai, a shallow eutrophic lake located in a semi-arid region in Northern China. The mean concentrations of CO2 and CH4 in porewater were 877.8 ± 31.0 µmol L-1 and 689.2 ± 45.0 µmol L-1, which were more than 50 and 20 times higher than those in the water column, respectively. The sediment was always a source of both gases for the water column. Porewater CO2 and CH4 concentrations and diffusive fluxes across the sediment-water interface showed significant temporal and spatial variations with mean diffusive fluxes of 887.3 ±124.7 µmol m-2 d-1 and 607.1 ± 68.0 µmol m-2 d-1 for CO2 and CH4, respectively. The temporal and spatial variations of CO2 and CH4 concentrations in porewater were associated with corresponding variations in dissolved organic carbon and dissolved nitrogen species. Temperature and dissolved organic carbon in surface porewater were the most important drivers of temporal variations in diffusive fluxes, whereas dissolved organic carbon and nitrogen were the main drivers of their spatial variations. Diffusive fluxes generally increased with increasing dissolved organic carbon and nitrogen in the porewater from the inflow to the outflow region of the lake. The estimated fluxes of both gases at the sediment-water interface were one order of magnitude lower than the emissions at the water surface, which were measured in a companion study. This indicates that diffusive fluxes across the sediment-water interface were not the main pathway for CO2 and CH4 emissions to the atmosphere. To improve the mechanistic understanding and predictability of greenhouse gas emissions from shallow lakes, future studies should aim to close the apparent gap in the CO2 and CH4 budget by combining improved flux measurement techniques with process-based modeling.

Investigation of water-soluble organic constituents and their spatio-temporal heterogeneity over the Tibetan Plateau.

Investigating the migration and transformation of carbonaceous and nitrogenous matter in the cryosphere areas is crucial for understanding global biogeochemical cycle and earth's climate system. However, water-soluble organic constituents and their transformation in multiple water bodies are barely investigated. Water-soluble organic carbon (WSOC) and organic nitrogen (WSON), and particulate black carbon (PBC) in multiple types of water bodies in eastern Tibetan Plateau (TP) cryosphere for the first time have been systematically investigated. Statistical results exhibited that from south to north and from east to west of this region, WSOC concentrations in alpine river runoff were gradually elevated. WSOC and nitrogenous matter in the alpine river runoff and precipitation in the glacier region presented distinct seasonal variations. WSON was the dominant component (63.4%) of water-soluble total nitrogen in precipitation over high-altitude southeastern TP cryosphere. Water-soluble carbonaceous matter dominated the carbon cycle in the TP cryosphere, but particulate carbonaceous matter in the alpine river runoff had a small fraction of the cryospheric carbon cycle. Analysis of optical properties illustrated that PBC had a much stronger light absorption ability (MAC-PBC: 2.28 ± 0.37 m2 g-1) than WSOC in the alpine river runoff (0.41 ± 0.26 m2 g-1). Ionic composition was dominated by SO42-, NO3-, and NH4+ (average: 45.13 ± 3.75%) in the snow of glaciers, implying important contribution of (fossil fuel) combustion sources over this region. The results of this study have essential implications for understanding the carbon and nitrogen cycles in high altitude cryosphere regions of the world. Future work should be performed based on more robust in-situ observations and measurements from multiple environmental medium over the cryosphere areas, to ensure ecological protection and high-quality development of the high mountain Asia.

Process mining for healthcare: Characteristics and challenges.

Process mining techniques can be used to analyse business processes using the data logged during their execution. These techniques are leveraged in a wide range of domains, including healthcare, where it focuses mainly on the analysis of diagnostic, treatment, and organisational processes. Despite the huge amount of data generated in hospitals by staff and machinery involved in healthcare processes, there is no evidence of a systematic uptake of process mining beyond targeted case studies in a research context. When developing and using process mining in healthcare, distinguishing characteristics of healthcare processes such as their variability and patient-centred focus require targeted attention. Against this background, the Process-Oriented Data Science in Healthcare Alliance has been established to propagate the research and application of techniques targeting the data-driven improvement of healthcare processes. This paper, an initiative of the alliance, presents the distinguishing characteristics of the healthcare domain that need to be considered to successfully use process mining, as well as open challenges that need to be addressed by the community in the future.

Persistence of the SARS-CoV-2 Antibody Response in Asymptomatic Patients in Correctional Facilities.

SARS-CoV-2 has caused a global health disaster with millions of death worldwide, and the substantial proportion of asymptomatic carriers poses a huge threat to public health. The long-term antibody responses and neutralization activity during natural asymptomatic SARS-CoV-2 infection are unknown. In this study, we used enzyme-linked immunosorbent assays (ELISA) and neutralization assay with purified SARS-CoV-2S and N proteins to study the antibody responses of 156 individuals with natural asymptomatic infection. We found robust antibody responses to SARS-CoV-2 in 156 patients from 6 to 12 months. Although the antibody responses gradually decreased, S-IgG was more stable than N-IgG. S-IgG was still detected in 79% of naturally infected individuals after 12 months of infection. Moderate to potent neutralization activities were also observed in 98.74% of patients 6 months after infection. However, this proportion decreased at 8-month (46.15%) and 10-month (39.11%) after infection, respectively. Only 23.72% of patients displayed potent neutralization activity at 12 months. This study strongly supports the long-term presence of antibodies against SARS-CoV-2 in individuals with natural asymptomatic infection, although the magnitude of the antibody responses started to cripple 6 months after infection.

Elevated salivary activity of mast cell chymase of periodontitis patients, and a new bradykinin generation cascade, mediating the cross-talks between mast cell and gingival fibroblast.

Activated-mast cells (MCs) within gingival-tissue of chronic-periodontitis (CP) patients, release various inflammatory-factors. Bradykinin is a nine-amino-acid peptide and pro-inflammatory mediator, produced through factor-XII-cascade or tryptase-cascade. The ability of MC-chymase in bradykinin generation has not been discussed yet. This study investigated the salivary levels of MC-chymase, high molecular weight kininogen (HMWK) and bradykinin of CP patients; examined the potential of MC-proteases in bradykinin production using biochemistry-models; and explored the effects of bradykinin on gingival fibroblasts (GFs). Saliva-samples were collected; MC-protease activities were detected; HMWK cleavage was assessed by western-blot and SDS-PAGE; bradykinin levels were measured using immunoassay. Primary GFs were extracted and cultured with or without bradykinin; cell-viability, gelatine-zymography and flow-cytometry were applied. Immunocytochemistry and western-blot were used to detect intracellular protein expressions of bradykinin-stimulated GFs. The data showed that the salivary-levels of MC-proteases, bradykinin, HMWK, and lactoferrin of CP-patients were increased. HMWK was cleaved by MC-chymase in-vitro, resulting in bradykinin generation. Bradykinin promoted cell proliferation, cell cycle and matrix-metalloproteinase-2(MMP-2) activity, and increased intracellular expressions of nuclear-factor-kappa-B(NF-κB), focal-adhesion-kinase(FAK), transforming-growth-factor-ß(TGF-ß), P38, P53 of GFs. MC-chymase promotes bradykinin production to stimulate GFs and to continue inflammation during CP development. A new BK-generation cascade found in this study provides a new basis for the pathogenesis of CP and the mechanism of continuous inflammation. The activation of MC-chymase/bradykinin-generation cascade depends on HMWK level and MC-chymase activity under inflammatory condition. MC-chymase contributes to bradykinin production, mediating the cross-talks between MCs and GFs. MC-chymase can be used as a therapeutic target and a salivary biomarker in this case.

Exceptional increases in fluvial sediment fluxes in a warmer and wetter High Mountain Asia.

Rivers originating in High Mountain Asia are crucial lifelines for one-third of the world's population. These fragile headwaters are now experiencing amplified climate change, glacier melt, and permafrost thaw. Observational data from 28 headwater basins demonstrate substantial increases in both annual runoff and annual sediment fluxes across the past six decades. The increases are accelerating from the mid-1990s in response to a warmer and wetter climate. The total sediment flux from High Mountain Asia is projected to more than double by 2050 under an extreme climate change scenario. These findings have far-reaching implications for the region's hydropower, food, and environmental security.

Assessment of vegetation growth and drought conditions using satellite-based vegetation health indices in Jing-Jin-Ji region of China.

Terrestrial vegetation growth activity plays pivotal roles on regional development, which has attracted wide attention especially in water resources shortage areas. The paper investigated the spatiotemporal change characteristics of vegetation growth activity using satellite-based Vegetation Health Indices (VHIs) including smoothed Normalized Difference Vegetation Index (SMN), smoothed Brightness Temperature (SMT), Vegetation Condition Index (VCI), Temperature Condition Index (TCI) and VHI, based on 7-day composite temporal resolution and 16 km spatial resolution gridded data, and also estimated the drought conditions for the period of 1982-2016 in Jing-Jin-Ji region of China. The Niño 3.4 was used as a substitution of El Niño Southern Oscillation (ENSO) to reveal vegetation sensitivity to ENSO using correlation and wavelet analysis. Results indicated that monthly SMN has increased throughout the year especially during growing season, starts at approximate April and ends at about October. The correlation analysis between SMN and SMT, SMN and precipitation indicated that the vegetation growth was affected by joint effects of temperature and precipitation. The VCI during growing season was positive trends dominated and vice versa for TCI. The relationships between VHIs and drought make it possible to identify and quantify drought intensity, duration and affected area using different ranges of VHIs. Generally, the intensity and affected area of drought had mainly decreased, but the trends varied for different drought intensities, regions and time periods. Large-scale global climate anomalies such as Niño 3.4 exerted obvious impacts on the VHIs. The Niño 3.4 was mainly negatively correlated to VCI and positively correlated to TCI, and the spatial distributions of areas with positive (negative) correlation coefficients were mainly opposite. The linear relationships between Niño 3.4 and VHIs were in accordance with results of nonlinear relationships revealed using wavelet analysis. The results are of great importance to assess the vegetation growth activity, to monitor and quantify drought using satellite-based VHIs in Jing-Jin-Ji region.

Eutrophication decreased CO2 but increased CH4 emissions from lake: A case study of a shallow Lake Ulansuhai.

Eutrophic lakes, especially shallow eutrophic lakes, disproportionately contribute to greenhouse gas (GHG) emissions. To investigate the effects of eutrophication on GHG dynamics, we conducted field measurements every three months from January 2019 to October 2019 in Lake Ulansuhai, a shallow eutrophic lake (mean depth of 0.7 m) located in a semi-arid region in Northern China. We found that Lake Ulansuhai was a predominantly source of atmospheric carbon dioxide (CO2); however, it converted to a CO2 sink in July due to eutrophication. It was also a strong source of methane (CH4) with a mean CO2 emission of 35.7 ± 12.1 mmol m-2 d-1 and CH4 emission of 5.9 ± 2.9 mmol m-2 d-1. The CO2 concentrations in most sites and CH4 concentrations in all sites were supersaturated, with the average partial pressure of CO2 (pCO2) being 654±34 µatm and the partial pressure of CH4 (pCH4) being 157±37 µatm. The partial pressures and emissions of the greenhouse gases exhibited substantial seasonal and spatial variations. The correlation analysis between the trophic level index and the partial pressure of the greenhouse gases indicated that eutrophication could significantly decrease the CO2 emissions but increase the CH4 emissions from the lake, resulting in a CH4 and CO2 emission ratio of approximately 2 in terms of global warming potential. Eutrophication decreased the pCO2 in the lake and subsequently increased the pCH4 due to nutrient input, thereby enhancing primary production. The results indicated that shallow eutrophic lakes in arid regions are strong sources of CH4 and that eutrophication could alter the greenhouse gas emission patterns.

Validation of an mRNA-based Urine Test for the Detection of Bladder Cancer in Patients with Haematuria.

BACKGROUND: In patients with haematuria, a fast, noninvasive test with high sensitivity (SN) and negative predictive value (NPV), which is able to detect or exclude bladder cancer (BC), is needed. A newly developed urine assay, Xpert Bladder Cancer Detection (Xpert), measures five mRNA targets (ABL1, CRH, IGF2, UPK1B, and ANXA10) that are frequently overexpressed in BC. OBJECTIVE: To validate the performance of Xpert in patients with haematuria. DESIGN, SETTING, AND PARTICIPANTS: Voided precystoscopy urine specimens were prospectively collected at 22 sites from patients without prior BC undergoing cystoscopy for haematuria. Xpert, cytology, and UroVysion procedures were performed. Technical validation was performed and specificity (SP) was determined in patients without BC. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Test characteristics were calculated based on cystoscopy and histology results, and compared between Xpert, cytology, and UroVysion. RESULTS AND LIMITATIONS: We included 828 patients (mean age 64.5 yr, 467 males, 401 never smoked). Xpert had an SN of 78% (95% confidence interval [CI]: 66-87) overall and 90% (95% CI: 76-96) for high-grade (HG) tumours. The NPV was 98% (95% CI: 97-99) overall. The SP was 84% (95% CI: 81-86). In patients with microhaematuria, only one HG patient was missed (NPV 99%). Xpert had higher SN and NPV than cytology and UroVysion. Cytology had the highest SP (97%). In a separate SP study, Xpert had an SP of 89% in patients with benign prostate hypertrophy and 92% in prostate cancer patients. CONCLUSIONS: Xpert is an easy-to-use, noninvasive test with improved SN and NPV compared with cytology and UroVysion, representing a promising tool for identifying haematuric patients with a low likelihood of BC who might not need to undergo cystoscopy. PATIENT SUMMARY: Xpert is an easy-to-perform urine test with good performance compared with standard urine tests. It should help identify (micro)haematuria patients with a very low likelihood to have bladder cancer.

Groundwater as a limited carbon dioxide source in a large river (the Yangtze River).

Groundwater discharge to river networks makes up a major source of riverine CO2 emission, available evidence however comes mainly from headwater streams which are directly connected to terrestrial ecosystems and spatially limited in terms of system size. Here relying on coupled water and CO2 mass balances, we quantified the groundwater-mediated CO2 input to the Yangtze River mainstem on an annual basis, where the mass balance of water provided physical constraints on CO2 exchange between the river and groundwater. A landscape topographic control of the groundwater-river interaction was proposed where mountain reaches preferentially receive water and CO2 discharge from the groundwater while plain alluvial reaches predominantly lose water to the aquifers. Groundwater CO2 inputs were however small in magnitude on all reaches (0.3-14% of the total CO2 emission and transport by the river) and unable to account for the discrepancy between surface evasion and internal metabolism in the river. Minor direct groundwater discharge to the reaches in comparison to smaller streams (negative to < 3.5% of the surface water flows) was concluded to be the main reason for low groundwater-sourced CO2 in the large river reaches.

Recent stepwise sediment flux increase with climate change in the Tuotuo River in the central Tibetan Plateau.

The riverine sediment flux (SF) is an essential pathway for nutrients and pollutants delivery and considered as an important indicator of land degradation and environment changes. With growing interest in environmental changes over the Tibetan Plateau (TP), this work investigated the variation of the SF in response to climate change in the headwater of the Yangtze River over the past 30 years. Annual time series of hydro-meteorological variables during 1986-2014 indicate significantly increasing trends of air temperature, precipitation, ground temperature, river discharge, suspended sediment concentration and SF. Stepwise changes were identified with significantly higher values of the above variables in 1998-2014 compared with 1986-1997, which could potentially be attributed to the strong 1997 El Niño event. Double-mass plots indicated that both meltwater and rainfall contributed to the increased river discharge while the increased SF mostly resulted from enhanced erosive power and transport capacities of the increased discharge. However, it was buffered by a decrease in sediment source due to the shift of maximum monthly rainfall from June/July to July/August during which period a denser vegetation cover prevents soil erosion. Partial least squares structural equation modeling analysis confirmed the dominance of warming on the increase of discharge amplified by increased precipitation. It also confirmed that the increased precipitation drives the increase in suspended sediment concentration. Both processes conspire and equally contribute to the stepwise increase of SF. This study provides important insights into the controlling processes for recent SF changes and gives guidance for water and soil conservation on the TP.

Light-absorbing impurities accelerating glacial melting in southeastern Tibetan Plateau.

Deposition of light-absorbing particles on glacier surfaces poses a series of adverse impacts on the cryospheric environment, climate and human health. Broad attention of the scientific community has been paid on insoluble light-absorbing impurities (ILAIs) in snow and ice on glaciers over the Tibetan Plateau (TP). However, systematic investigation of ILAIs in snowpack of glaciers on the TP is scarce. In this study, the properties and darkening effect of ILAIs in snowpack on glaciers are extensively investigated in the southeast of TP. Results show that ILAIs concentrations in multiple types of snow and ice samples were significantly different. Snowpit depths varied substantially from one profile to another during May and June 2016. The average concentrations of ILAIs in snowpits increase as snow melting progresses. Black carbon (BC) and dust cause snow albedo reduction more in snow with larger grain size Re. Based on a radiative transfer model calculation, the average albedo reduction induced by BC in the snowpack was 0.141 ± 0.02, and associated daily maximum radiative forcing (RF) was 72.97 ± 12.7 W m-2. BC is a controlling light-absorbing factor in snowpack and causes substantial albedo reduction and thus the associated daily maximum RF. The maximum reduction of snow cover duration was 4.56 ± 0.71 days caused by BC and dust in snowpack in southeastern TP. The average mass absorption cross-section (MAC) of BC from multiple snowpits was 3.26 ± 0.46 m2 g-1, which represents a typical value of MAC in snow on glaciers, but it is type-dependent of snow/ice samples. Tropospheric aerosols vertically extended up to 8 km over the TP and its surrounding areas, which indicates the transport of aerosols from remote sources through elevated pathways. A large amount of carbon stored in the brittle glaciers can be potentially released with meltwater runoff under a warming climate. This study provides a new insight for investigating carbonaceous and light-absorbing particles in glacierization areas.

Interactive effects of hydrological conditions on soil respiration in China's Horqin sandy land: An example of dune-meadow cascade ecosystem.

Soil moisture (Ms) strongly influences dynamic changes in soil respiration (Rs) and is thus an important factor when predicting soil carbon emissions. However, the various sources of Ms (rainfall, groundwater, and condensation) exert complicated and uncertain effects on Rs. This study examined the growth seasonal variation (from April to October) of Rs and the diurnal variation in a cascade ecosystem consisting of sandy bare ground, a transitional artificial Populus forest, and a meadow Phragmites communis community in China's Horqin sandy land. Simultaneous measurements of the 0-10 cm depth soil temperature (Ts) and Ms, rainfall, the surface air relative humidity and the groundwater depth were collected. The results revealed that in sandy bare ground with Ms below field capacity, Ms had a greater impact on Rs than Ts, and rainfall could increase Rs. The effect of condensation on Rs during periods of continuous drought could not be ignored. In the meadowlands with Ms above field capacity, the groundwater affected Rs indirectly by regulating Ms and the relationship with Ts, and rainfall had an adverse effect on Rs. The effects of rainfall, Ms and Ts on Rs were minimum as Ms approached the saturation water content. In the transitional forest, Ms and Ts were the main factors controlling Rs. The most favorable Ms for Rs was close to the field capacity. The results emphasize that field capacity and saturation water content are the demarcation points of a soil carbon emissions prediction model, and the effect of different hydrological conditions and Ts on Rs at each segment are reconsidered accordingly. Ultimately, the carbon emission patterns of the cascade ecosystems in arid and semi-arid areas are extremely complicated and have to be considered specially for estimating terrestrial carbon emissions.