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Soil organic carbon (SOC) is a mixture of various carbon (C) compounds with different stability, which can be distinctly affected by the priming effect (PE). However, little is known about how the PE changes with SOC stability. We address this issue by combining results from two experiments and a metaanalysis. We found that the PE increased with the prolongation of soil preincubation, suggesting that higher PE occurred for more stable SOC than for labile SOC. This was further supported by the metaanalysis of 42 observations. There were significant negative relationships between the difference in PE (ΔPE) between labile and more stable SOC and their differences in SOC, microbial biomass C and soil C : N ratio, indicating that soil C availability exerts a vital control on ΔPE. We conclude that, compared with labile SOC, stable SOC can be more vulnerable to priming once microbes are provided with exogenous C substrates. This high vulnerability of stable SOC to priming warrants more attention in future studies on SOC cycling and global change.

Global changes can alter plant inputs from both above- and belowground, which, thus, may differently affect soil carbon and microbial communities. However, the general patterns of how plant input changes affect them in forests remain unclear. By conducting a meta-analysis of 3193 observations from 166 experiments worldwide, we found that alterations in aboveground litter and/or root inputs had profound effects on soil carbon and microbial communities in forest ecosystems. Litter addition stimulated soil organic carbon (SOC) pools and microbial biomass, whereas removal of litter, roots or both (no inputs) decreased them. The increased SOC under litter addition suggested that aboveground litter inputs benefit SOC sequestration despite accelerated decomposition. Unlike root removal, litter alterations and no inputs altered particulate organic carbon, whereas all detrital treatments did not significantly change mineral-associated organic carbon. In addition, detrital treatments contrastingly altered soil microbial community, with litter addition or removal shifting it toward fungi, whereas root removal shifting it toward bacteria. Furthermore, the responses of soil carbon and microbial biomass to litter alterations positively correlated with litter input rate and total litter input, suggesting that litter input quantity is a critical controller of belowground processes. Taken together, these findings provide critical insights into understanding how altered plant productivity and allocation affects soil carbon cycling, microbial communities and functioning of forest ecosystems under global changes. Future studies can take full advantage of the existing plant detritus experiments and should focus on the relative roles of litter and roots in forming SOC and its fractions.

The adoption of diverse resource acquisition strategies is critical for plant growth and species coexistence. Root phosphatase is of particular importance in the acquisition of soil phosphorus (P), yet it is often overlooked in studies of root trait syndromes. Here, we evaluated the role of root phosphatase activity (RPA) within the root economics space and the order-based variation of RPA, as well as the correlations between RPA and a suite of leaf traits and soil properties over a range of evergreen tree species in a subtropical forest. Root phosphatase activity exhibited a high degree of inter-specific variation. We found that there were two leading dimensions of the multidimensional root economics space, the root diameter-specific root length axis (collaboration trait gradient) and the root tissue density-root nitrogen concentration axis (classical trait gradient), and RPA aligned with the former. Root phosphatase activity is used as a 'do it yourself' strategy of soil P acquisition, and was found to be inversely correlated with mycorrhizal colonization, which suggests a trade-off in plant P acquisition strategies. Compared with soil and foliar nutrient status, root traits mattered most for the large inter-specific changes in RPA. Furthermore, RPA generally decreased from first- to third-order roots. Taken together, such diverse P-acquisition strategies are conducive to plant coexistence within local forest communities. The use of easily measurable root traits and their tight correlations with RPA could be a feasible and promising approach to estimating species-specific RPA values, which would be helpful for better understanding plant P acquisition and soil P cycling.

Arbuscular mycorrhizal (AM) fungi play important roles in carbon (C), nitrogen (N) and phosphorus (P) cycling of terrestrial ecosystems. The impact of increasing N deposition on AM fungi will inevitably affect ecosystem processes. However, generalizable patterns of how N deposition affects AM fungi remains poorly understood. Here we conducted a global-scale meta-analysis from 94 publications and 101 sites to investigate the responses of AM fungi to N addition, including abundance in both intra-radical (host roots) and extra-radical portion (soil), richness and diversity. We also explored the mechanisms of N addition affecting AM fungi by the trait-based guilds method. Results showed that N addition significantly decreased AM fungal overall abundance (-8.0%). However, the response of abundance in intra-radical portion was not consistent with that in extra-radical portion: root colonization decreased (-11.6%) significantly, whereas extra-radical hyphae length density did not change significantly. Different AM fungal guilds showed different responses to N addition: both the abundance (spore density) and relative abundance of the rhizophilic guild decreased significantly under N addition (-29.8% and -12.0%, respectively), while the abundance and relative abundance of the edaphophilic guild had insignificant response to N addition. Such inconsistent responses of rhizophilic and edaphophilic guilds were mainly moderated by the change of soil pH and the response of root biomass, respectively. Moreover, N addition had an insignificant negative effect on AM fungal richness and diversity, which was strongly related with the relative availability of soil P (i.e. soil available N/P ratio). Collectively, this meta-analysis highlights that considering trait-based AM fungal guilds, soil P availability and host plant C allocation can greatly improve our understanding of the nuanced dynamics of AM fungal communities under increasing N deposition.

Soil organic carbon (SOC) is an indicator of soil fertility. Global warming accelerates SOC decomposition, consequently, resulting in land degradation. Characterization of the response of SOC decomposition to temperature is important for predicting land development. A simulation model based on temperature sensitivity (Q₁₀) of SOC decomposition has been used to predict SOC response to climate warming. However, uncertain Q₁₀ leads to substantial uncertainties in the predictions. A major uncertainty comes from the interference of rainfall. To minimize this interference, we sampled surface (0–5 cm) soils along an isohyet across a temperature gradient in the Qinghai–Tibetan Plateau. The Q₁₀ of bulk soil and the four soil fractions, such as light fraction (LightF), particulate organic matter (POM), hydrolyzable fraction (HydrolysF), and recalcitrant fraction (RecalcitF), were studied by ¹⁴C dating. Turnover time follows the order: LightF < POM < bulk soil < HydrolysF < RecalcitF. The Q₁₀ follows the order: LightF (1.0) = POM (1.0) < HydrolysF (3.63) < bulk soil (5.93) < RecalcitF (7.46). This indicates that stable fractions are much more sensitive to temperature than labile fractions. We also suggest that protection mechanisms rather than molecular composition regulate SOC turnover. A new concept 'protection sensitivity' of SOC decomposition was proposed. Protection sensitivity relates to protection type and primarily controls Q₁₀ variation. A simulation model based on the Q₁₀ of individual fractions predicted SOC change and land development in the Qinghai–Tibetan Plateau in the next 100 years much effectively as compared to simulations based on one‐pool model (Q₁₀ = 2) or bulk soil (Q₁₀ = 5.93).

Oncolytic viruses have found a good place in the treatment of cancer. Administering oncolytic viruses directly or by applying genetic changes can be effective in cancer treatment through the lysis of tumor cells and, in some cases, by inducing immune system responses. Moreover, oncolytic viruses induce antitumor immune responses via releasing tumor antigens in the tumor microenvironment (TME) and affect tumor cell growth and metabolism. Despite the success of virotherapy in cancer therapies, there are several challenges and limitations, such as immunosuppressive TME, lack of effective penetration into tumor tissue, low efficiency in hypoxia, antiviral immune responses, and off-targeting. Evidence suggests that oncolytic viruses combined with cancer immunotherapy-based methods such as immune checkpoint inhibitors and adoptive cell therapies can effectively overcome these challenges. This review summarizes the latest data on the use of oncolytic viruses for the treatment of cancer and the challenges of this method. Additionally, the effectiveness of mono, dual, and triple therapies using oncolytic viruses and other anticancer agents has been discussed based on the latest findings.

This paper aims to probe into the effect of sweroside (SOS) in osteoporosis (OP) and explains mechanisms of its molecular. Applying the ovariectomized (OVX) mouse model investigates the preventive effect of SOS against postmenopausal OP after 3 months of SOS treatment (120 mg/kg/day). Using hematoxylin and eosin (HE) staining and micro computed tomography (CT) observed the morphology of OP in each group. Immunohistochemical staining (IHC) was used to examine osteoblast markers. Experiments in vitro, bone marrow mesenchymal stem cells (BMSCs) from C57/BL6 mice were treated with SOS for 14 days. The staining of alizarin red and alkaline phosphatase activity were measured, and the presentation of osteoblast markers was detected by quantitative reverse transcription PCR. BMSCs were also treated with 1 μg/mL SOS with or without rapamycin, the expression of protein S6 (PS6), P-mTOR, runt-related transcription factor 2 (RUNX2), OSX, and osteocalcin (OCN) was detected by Western blotting. Experiments in vivo, HE results show that SOS can alleviate OP, CT results show that there are lower trabecular thickness, bone mineral density, and trabecular number in control OVX mice than those in the OVX + SOS group. IHC results showed that SOS can promote the expression of osteogenic markers and immunofluorescent results show that SOS can promote mTORC1 signal activation. Experiments in vitro revealed that SOS stimulated the activation of the mTORC1 signaling pathway and upregulated RUNX2, OSX, and OCN, rapamycin can reverse it. Our findings demonstrated that differentiated BMSCs into osteoblasts can be promoted by SOS via upregulating the expression of P-mTOR, PS6, RUNX2, OSX, and OCN. SOS effectively prevented OP by hyperactivation of the mTORC1/PS6 signaling pathway.

Rhizosphere priming effects (RPEs) play a central role in modifying soil organic matter mineralization. However, effects of tree species and intraspecific competition on RPEs are poorly understood. We investigated RPEs of three tree species (larch, ash and Chinese fir) and the impact of intraspecific competition of these species on the RPE by growing them at two planting densities for 140 d. We determined the RPE on soil organic carbon (C) decomposition, gross and net nitrogen (N) mineralization and net plant N acquisition. Differences in the RPE among species were associated with differences in plant biomass. Gross N mineralization and net plant N acquisition increased, but net N mineralization decreased, as the RPE on soil organic C decomposition increased. Intraspecific competition reduced the RPE on soil organic C decomposition, gross and net N mineralization, and net plant N acquisition, especially for ash and Chinese fir. Microbial N mining may explain the overall positive RPEs across species, whereas intensified plant-microbe competition for N may have reduced the RPE with intraspecific competition. Overall, the species-specific effects of tree species play an important role in modulating the magnitude and mechanisms of RPEs and the intraspecific competition on soil C and N dynamics.

In order to closely mimic a multi-cell state in hematopoietic stem/progenitor cells (HSC/HPCs) vascular niche, we co-cultured human bone marrow mesenchymal stem cells (hBMSCs) and human umbilical vein endothelial cells (HUVECs) without any cytokines as feeder cells and applied bio-derived bone from human femoral metaphyseal portion as scaffold to develop a new HSC/HPCs three-dimensional culture system (named 3D-Mix cultures). Scanning electron and fluorescent microscopy showed excellent biocompatibility of bio-derived bone to hBMSCs and HUVECs in vitro. Flow cytometry analysis and quantitative real-time polymerase chain reaction (qPCR) assay of p21 expression demonstrated that 3D-Mix could promote self-renewal and ex vivo expansion of HSCs/HPCs significantly higher than 3D-hMSC and 3D-HUVEC. Long-term culture initiating cell (LTC-IC) confirmed that 3D-Mix had the most powerful activity of maintaining multipotent differentiation of primitive cell subpopulation in HSCs. The nonobese diabetic/severe combined immunodeficiency (NOD/SCID) repopulating cell (SRC) assay demonstrated that 3D-Mix promoted the expansion of long-term primitive transplantable HSCs. qPCR of alkaline phosphatase (ALP) and osteocalcin (OC) demonstrated that HUVECs enhanced the early osteogenic differentiation of BMSCs. Western blot and qPCR revealed that HUVECs activated Wnt/β-catenin signaling in hBMSCs inducing Notch signal activation in HSCs. Our study indicated that interaction between hMSCs and HUVECs may have a critical role in to influent on HSCs/HPCs fate in vitro. These results demonstrated that the 3D-Mix have the ability to support the maintenance and proliferation of HSCs/HPCs in vitro.

The response of soil organic carbon (SOC) pools to globally rising surface temperature crucially determines the feedback between climate change and the global carbon cycle. However, there is a lack of studies investigating the temperature sensitivity of decomposition for decadally cycling SOC which is the main component of total soil carbon stock and the most relevant to global change. We tackled this issue using two decadally (13) C-labeled soils and a much improved measuring system in a long-term incubation experiment. Results indicated that the temperature sensitivity of decomposition for decadally cycling SOC (>23 years in one soil and >55 years in the other soil) was significantly greater than that for faster-cycling SOC (

The reactions of 4,4′-dihydroxybiphenyl-3,3′-disulfonic acid (H4L) with group 1 and 2 metal salts in aqueous solution lead to six metal sulfonate complexes, [K2(H2L)]n (1), {[Cs2(H2L)(H2O)]n·nH2O} (2), 2[Mg(H2O)6]2+·2(H2L)2–·2H2O (3), {[Ca(H2L)(H2O)2]n·4nH2O} (4), {[Sr(H2L)(H2O)4]n·3nH2O} (5), and {[Ba(H2L)(H2O)]n·nH2O} (6), which have been characterized by elemental analysis, IR spectroscopy, thermogravimetry (TG), photoluminescence (PL) spectroscopy, powder XRD, and single-crystal XRD. Complexes 1, 2, and 6 exhibit 3D pillared-layered networks formed by M–O–S layers bridged by the biphenyl rings of H2L2– dianions. The [Mg(H2O)6]2+ cations and sulfonate groups in 3 are held together by second-sphere interactions to generate layer motifs. Complex 4 presents a layer structure formed by Ca–O chains bridged by the biphenyl rings of H2L2– dianions. Complex 5 has a 3D interdigitating architecture (2D + 2D 3D), in which the 44 hydrogen-bonding layer is constructed from linear chains. Meanwhile, the recrystallization of H4L from aqueous solution affords the supramolecular complex 2(H3O+)·(H2L)2–·3H2O (S1), which exhibits a 3D pillared-layered network. The solid-state luminescence properties demonstrate that 1–6 exhibit violet emission at room temperature and can sensitize EuIII and TbIII ions to exhibit their characteristic emissions.

The relationship between climate/productivity and historical/regional contingency and their relative influence on geographical patterns of species richness (GPSR) are still unresolved. Based on field data from 1494 plots from forests on 63 mountains across China, we document the GPSR for forest communities. Regression tree and generalized linear models were used to explore the discreteness and gradient of the distribution of tree species richness (α-diversity), and to estimate the correlations of climate, historical floristic region, and local habitat with species richness. The collinearity between climatic variables and region were further disentangled; and the spatial autocorrelation in the patterns of α-diversity and the residuals of alternative predictive models were compared. Overall, 75% of variation in plot-based α-diversity of trees was accounted for by all variables included, and about 66.5%, 64.5% and 27.9% by climate, region, and local habitat respectively. Importantly, the explanatory power of these variables differed in particular for coniferous, deciduous broadleaved and evergreen broadleaved species. Ambient temperature was more important for α-diversity of trees than were the other climatic variables across China. Spatial autocorrelation in the pattern of α-diversity could be accounted for mainly by spatial variation climate. The concordance between tree α-diversity, historical flora, contemporary climate, and Quaternary climate change mode suggests the climate/productivity and historical/regional contingency both contribute to the GPSR in a complimentary manner. Taken together, our results provide unique evidence to link of the effects of contemporary climate and historical climate change on species richness across scales.

Monitoring changes in vegetation growth has been the subject of considerable research during the past several decades, because of the important role of vegetation in regulating the terrestrial carbon cycle and the climate system. In this study, we combined datasets of satellite-derived Normalized Difference Vegetation Index (NDVI) and climatic factors to analyze spatio-temporal patterns of changes in vegetation growth and their linkage with changes in temperature and precipitation in temperate and boreal regions of Eurasia (> 23.5°N) from 1982 to 2006. At the continental scale, although a statistically significant positive trend of average growing season NDVI is observed (0.5 × 10−3 year−1, P = 0.03) during the entire study period, there are two distinct periods with opposite trends in growing season NDVI. Growing season NDVI has first significantly increased from 1982 to 1997 (1.8 × 10−3 year−1, P < 0.001), and then decreased from 1997 to 2006 (−1.3 × 10−3 year−1, P = 0.055). This reversal in the growing season NDVI trends over Eurasia are largely contributed by spring and summer NDVI changes. Both spring and summer NDVI significantly increased from 1982 to 1997 (2.1 × 10−3 year−1, P = 0.01; 1.6 × 10−3 year−1P < 0.001, respectively), but then decreased from 1997 to 2006, particularly summer NDVI which may be related to the remarkable decrease in summer precipitation (−2.7 mm yr−1, P = 0.009). Further spatial analyses supports the idea that the vegetation greening trend in spring and summer that occurred during the earlier study period 1982–1997 was either stalled or reversed during the following study period 1997–2006. But the turning point of vegetation NDVI is found to vary across different regions.

The seroprevalence of Kaposi's sarcoma-associated herpesvirus (KSHV) in Chinese patients with chronic hepatitis B, the relationship between KSHV and hepatitis B virus (HBV) infection, and the influence of glycyrrhizic acid on KSHV replication in vivo are undefined. Plasma was collected from 211 patients with chronic hepatitis B. Antibody to KSHV ORF65 was evaluated by ELISA, and real-time PCR was used to quantify KSHV DNA and HBV DNA. The KSHV ORF65 positivity rate in patients with chronic hepatitis B was found to be 28% (59/211): 27.3% (44/161) in males and 30% (15/50) in females (P0.05). The seroprevalence of KSHV increased with age until reaching the highest rate (37.1%) in the 31-40 years age group. HBV DNA loads in patients with chronic hepatitis B infected with KSHV were higher than those without KSHV infection (9.2 log (10) IU/ml vs. 7.8 log (10) IU/ml, P0.05). The average KSHV DNA loads in patients with HBV genotype B, C, and mixed (B/C) were 409.1, 484.5, and 352 copies/ml, respectively (P0.05). Patients treated with glycyrrhizic acid had lower KSHV DNA levels than those without therapy (204.7 copies/ml vs. 533.9 copies/ml, P0.05). The KSHV ORF65 positivity rates tended to increase with age, but were not related to gender or HBV genotypes. The data indicated the interaction between KSHV and HBV, and the inhibiting effect of glycyrrhizic acid on KSHV replication in patients with chronic hepatitis B.

The temperature sensitivity of soil organic matter (SOM) decomposition has been a crucial topic in global change research, yet remains highly uncertain. One of the contributing factors to this uncertainty is the lack of understanding about the role of rhizosphere priming effect (RPE) in shaping the temperature sensitivity. Using a novel continuous 13C-labeling method, we investigated the temperature sensitivity of RPE and its impact on the temperature sensitivity of SOM decomposition. We observed an overall positive RPE. The SOM decomposition rates in the planted treatments increased 17–163% above the unplanted treatments in three growth chamber experiments including two plant species, two growth stages, and two warming methods. More importantly, warming by 5 °C increased RPE up to threefold, hence, the overall temperature sensitivity of SOM decomposition was consistently enhanced (Q10 values increased 0.3–0.9) by the presence of active rhizosphere. In addition, the proportional contribution of SOM decomposition to total soil respiration was increased by soil warming, implying a higher temperature sensitivity of SOM decomposition than that of autotrophic respiration. Our results, for the first time, clearly demonstrated that root–soil interactions play a crucial role in shaping the temperature sensitivity of SOM decomposition. Caution is required for interpretation of any previously determined temperature sensitivity of SOM decomposition that omitted rhizosphere effects using either soil incubation or field root-exclusion. More attention should be paid to RPE in future experimental and modeling studies of SOM decomposition.

The soils of the Qinghai-Tibetan Plateau store a large amount of organic carbon, but the magnitude, spatial patterns and environmental controls of the storage are little investigated. In this study, using data of soil organic carbon (SOC) in 405 profiles collected from 135 sites across the plateau and a satellite-based dataset of enhanced vegetation index (EVI) during 2001‐2004, we estimated storage and spatial patterns of SOC in the alpine grasslands. We also explored the relationships between SOC density (soil carbon storage per area) and climatic variables and soil texture. Our results indicated that SOC storage in the top 1m in the alpine grasslands was estimated at 7.4Pg C (1Pg 510 15 g), with an average density of 6.5kgm � 2 . The density of SOC decreased from the southeastern to the northwestern areas, corresponding to the precipitation gradient. The SOC density increased significantly with soil moisture, clay and silt content, but weakly with mean annual temperature. These variables could together explain about 72% of total variation in SOC density, of which 54% was attributed to soil moisture, suggesting a key role of soil moisture in shaping spatial patterns of SOC density in the alpine grasslands.

The first two-dimensional lanthanum(III) coordination polymer, [La(1,5-NDS)1.5(H2O)5]n(1) (1,5-NDS2− = 1,5-naphthalenedisulfonate), was synthesized and structurally characterized by single-crystal X-ray diffraction analysis. The disulfonate ligands act in the η1:η1:μ2 and η1:η1:η1:μ3 binding modes to link the LaO9 tricapped trigonal prisms into a lamellar structure. It exhibits strong purple emission in the solid state.

The relationship between vegetation phenology and climate is a crucial topic in global change research because it indicates dynamic responses of terrestrial ecosystems to climate changes. In this study, we investigate the possible impact of recent climate changes on growing season duration in the temperate vegetation of China, using the advanced very high resolution radiometer (AVHRR)/normalized difference vegetation index (NDVI) biweekly time-series data collected from January 1982 to December 1999 and concurrent mean temperature and precipitation data. The results show that over the study period, the growing season duration has lengthened by 1.16 days yr � 1 in temperate region of China. The green-up of vegetation has advanced in spring by 0.79 days yr � 1 and the dormancy delayed in autumn by 0.37 days yr � 1 . The dates of onset for phenological events are most significantly related with the mean temperature during the preceding 2–3 months. A warming in the early spring (March to early May) by 11C could cause an earlier onset of green-up of 7.5 days, whereas the same increase of mean temperature during autumn (mid-August through early October) could lead to a delay of 3.8 days in vegetation dormancy. Variations in precipitation also influenced the duration of growing season, but such influence differed among vegetation types and phenological phases.

A palladium-catalyzed tandem reaction of 2-alkynylphenol with 2-alkynylvinyl bromide gives rise to cyclopenta[c]chromenes in good yields. Three bonds are formed during the process and a double insertion of triple bonds is believed to be the key step.