Advances in the assessment of cosmetic outcomes, sensory alteration in surgical areas, and health-related quality of life of endoscopic thyroidectomy.

BACKGROUND: Endoscopic thyroidectomy has been preliminarily proven effective and safe for thyroid diseases. The cosmetic outcomes and life quality are critical contents of postoperative assessment. This review will primarily focus on the assessment methods and results related to cosmetic outcomes, sensory alteration of surgical area, and quality of life following endoscopic thyroidectomy. METHODS: A comprehensive search of published articles within the last decade was conducted using the terms "endoscopic/robotic thyroidectomy," "patient satisfaction scores," "questionnaire," "quality of life," and "cosmetic" in PubMed. RESULTS: Assessment methods for postoperative cosmetic satisfaction and sensory alterations encompassed verbal/visual analog scales, scar evaluations, Semmes-Weinstein monofilament tests, and more. The evaluation of postoperative quality of life in endoscopic thyroidectomy involved tools such as SF-36, SF-12, thyroid-specific questionnaires, thyroid cancer-specific quality of life questionnaires (THYCA-QOL), as well as assessments related to voice and swallow function. The cosmetic results of endoscopic thyroidectomy generally surpassed those of open thyroidectomy, while the quality of life in endoscopic procedures was either superior or equivalent to that in open thyroidectomy, especially with respect to general health, role emotion, and vitality. CONCLUSIONS: Assessments of cosmetic outcomes and sensory alterations following endoscopic thyroidectomy predominantly relied on patients' subjective feelings. The objective and subjective perspectives of scar assessments remain underutilized. In addition, postoperative laryngoscopy and voice function assessments in endoscopic thyroidectomy procedures require more attention.

Small extracellular vesicles derived from PD-L1-modified mesenchymal stem cell promote Tregs differentiation and prolong allograft survival.

We aimed to explore whether programmed cell death protein-1 ligand (PD-L1) modification on small extracellular vesicles (sEVs) could promote T regulatory cells (Tregs) differentiation. In this study, it was confirmed that under physiological conditions, PD-L1 expression was minimal in the MSCs and absent in the MSC-sEVs. A vector harboring the PD-L1 gene was constructed and transfected into bone marrow mesenchymal stem cells (BM-MSCs). By extracting the sEVs of these modified BM-MSCs and monitoring the expression of the PD-L1 protein, however, PD-L1 expression was substantially increased in the MSCs and concentrated in the sEVs. Then, the rat naïve CD4 + T cells were cocultured with the sEVs derived from the PD-L1-modified MSCs (sEVsPD-L1). By flow cytometry, a higher percentage of Tregs and anti-inflammatory downstream cytokines (including IL-2, IFN-γ, TGF-ß, IL-10) was detected in the sEVsPD-L1 group than that in the control group treated by either sEVs in wild type, modified by empty vector, or blank control. Suppressive effect on CD4 + T cell proliferation serves as additional evidence to support the immunoregulation capacity of sEVsPD-L1. The animal model of vascularized composite allograft further confirmed that PD-L1-modified sEVs induce an immune tolerance, by clinically observation, histopathology, T cell fate and cell product. In conclusion, sEVsPD-L1 efficiently promotes Treg cell differentiation in vitro and in vivo, which suggests their therapeutic potential in the treatment of allograft rejection.

Pan-cancer analysis of the oncogenic role of discs large homolog associated protein 5 (DLGAP5) in human tumors.

BACKGROUND: In recent years, there have been many studies on the relationship between DLGAP5 and different types of cancers, yet there is no pan-cancer analysis of DLGAP5. Therefore, this study aims to analyze the roles of DLGAP5 in human tumors. METHODS: Firstly, we evaluated the expression level of DLGAP5 in 33 types of tumors throughout the datasets of TCGA (Cancer Genome Atlas) and GEO (Gene Expression Synthesis). Secondly, we used the GEPIA2 and Kaplan-Meier plotter to conduct Survival prognosis analysis. Additionally, cBioPortal web was utilized to analyze the genetic alteration of DLGAP5, after which we selected hepatocellular carcinoma (HCC) cell lines to define the function of DLGAP5. Last but not least, we performed immune infiltration analysis and DLGAP5-related gene enrichment analysis. RESULTS: DLGAP5 is highly expressed in most type of cancers, and there is a significant correlation between the expression of DLGAP5 and the prognosis of cancer patients. We have observed that DLGAP5 promotes the proliferation and invasion of hepatocellular carcinoma (HCC) cell lines. We also found that DLGAP5 expression was related with the CD8+ T-cell infiltration status in kidney renal clear cell carcinoma, uveal melanoma, and thymoma, and cancer-associated fibroblast infiltration was observed in breast invasive carcinoma, kidney renal papillary cell carcinoma and testicular germ cell tumors. In addition, enrichment analysis revealed that cell cycle- and oocyte meiosis-associated functions were involved in the functional mechanism of DLGAP5. CONCLUSIONS: Taken together, our unpresented pan-cancer analysis of DLGAP5 provides a relatively integrative understanding of the oncogenic role of DLGAP5 in various tumors. DLGAP5 may prompt HCC cellular proliferation, invasion and metastasis. All of these provides solid basement and will promote more advanced understanding the role of DLGAP5 in tumorigenesis and development from the perspective of clinical tumor samples and cells.

Circ_0003747 promotes thyroid cancer progression by sponging miR-338-3p to upregulate PLCD3 expression.

The circular RNAs (circRNAs) involved in competitive endogenous RNA (ceRNA) mechanism are critical modulators affecting pathogenesis of thyroid carcinoma (TC). The study's goal was to investigate the effects of circ 0003747 on the biological progression of papillary thyroid cancer (PTC). Normal thyroid cells Nthy-ori3-1 and TC derived cell lines were used in our study. Sanger sequencing and RNase R treatment were utilized for validating the circular structure of circ_0003747. In our work, circ_0003747 was found to be highly expressed in TC cells. Circ_0003747 knockdown reduced TC cell viability, proliferation, migration, and invasion while increasing cell apoptosis. Circ_0003747 targeted and negatively regulated miR-338-3p expression. Besides, miR-338-3p interacted with PLCD3 to repress its expression. Overexpression of miR-338-3p inhibited TC cell progression, and PLCD3 reversed these effects. Furthermore, PLCD3 overexpression reversed the effects of circ_0003747 knockdown on TC cells. Additionally, the knockdown of circ_0003747 remarkably suppressed tumour size and growth, restrained PLCD3 expression and promoted miR-338-3p expression in nude mice. In conclusion, circ_0003747 facilitated the biological progression of TC by modulating the miR-338-3p/PLCD3 axis, and it may be a new target for TC treatment. [Figure: see text]Abbreviations: TC: Thyroid carcinoma; PTC: Papillary thyroid carcinoma; CircRNAs: Circular RNAs; MiRNA: MicroRNA; EMT: Epithelial-mesenchymal transition; HCC: Hepatocellular carcinoma; PLCD3: Phospholipase C Delta 3; CeRNA: Competitive endogenous RNA.

Greenhouse gas emissions and environmental drivers in different natural wetland regions of China.

Wetlands sequestrate carbon at the highest rate than any other ecosystems on Earth. However, the spatial and temporal dynamics of GHGs emissions from the wetland ecosystems in China are still elusive. We synthesized 166 publications that contain 462 in situ measurements of GHGs emissions from the natural wetlands in China, and further analyzed the variability and the drivers of GHGs emissions in eight subdivisions of China's wetlands. The results show that the current studies are mainly concentrated in the estuaries, Sanjiang Plain, and Zoige wetlands. The average CO2 emissions, CH4 fluxes and N2O fluxes from Chinese wetlands were 218.84 mg·m-2·h-1, 1.95 mg·m-2·h-1 and 5.8 × 10-2 mg·m-2·h-1, respectively. The global warming potential (GWP) of China's wetlands was estimated to be 1881.36 TgCO2-eq·yr-1, with CO2 emissions contributing more than 65% to the GWP value. The combined GWP values of Qinghai-Tibet Plateau wetlands, coastal wetlands and northeastern wetlands account for 84.8% of GWP of China's wetlands. Correlation analysis showed that CO2 emissions increased with the increasing mean annual temperature, elevation, annual rainfall, and wetland water level, but decreased with soil pH. CH4 fluxes increased with the mean annual temperature and soil water content but decreased with the redox potential. This study analyzed the drivers of GHGs emissions from wetland ecosystems at the national scale, and GWP values of eight wetland subregions of China were comprehensively assessed. Our results are potentially useful for the global GHGs inventory, and can help assess the response of GHGs emissions of wetland ecosystem to environmental and climate change.

The new 'coN' staging system combining lymph node metastasis and tumour deposit provides a more accurate prognosis for TNM stage III colon cancer.

OBJECTIVE: Despite controversy over its origin and definition, the significance of tumour deposit (TD) has been underestimated in the tumour node metastasis (TNM) staging system for colon cancer, especially in stage III patients. We aimed to further confirm the prognostic value of TD in stage III colon cancer and to establish a more accurate 'coN' staging system combining TD and lymph node metastasis (LNM). METHODS: Information on stage III colon cancer patients with a definite TD status was retrospectively collected from the Surveillance, Epidemiology and End Results (SEER) database between 2010 and 2017. The effect of TD on prognosis was estimated using Cox regression analysis. Maximally selected rank statistics were used to select the optimal cut-off value of TD counts. The predictive power of conventional N staging and the new coN staging was evaluated and compared by Akaike's information criterion (AIC), Harrell's concordance index (C-index) and time-dependent receiver operating characteristic (ROC) curves. Clinicopathological data of stage III colon cancer patients in the Xiangya database from 2014 to 2018 were collected to validate the coN staging system. RESULTS: A total of 39,185 patients with stage III colon cancer were included in our study: 38,446 in the SEER cohort and 739 in the Xiangya cohort. The incidence of TD in stage III colon cancer was approximately 30% (26% in SEER and 30% in the Xiangya database). TD was significantly associated with poorer overall survival (OS) (HR = 1.37, 95% CI 1.31-1.44, p < 0.001 in SEER). The optimal cut-off value of TD counts was 4, and the patients were classified into the TD0 (count = 0), TD1 (count = 1-3) and TD2 (count ≥ 4) groups accordingly. The estimated 5-year OS was significantly different among the three groups (69.4%, 95% CI 68.8%-70.0% in TD0; 60.5%, 95% CI 58.9%-62.2% in TD1 and 42.6%, 95% CI 39.2%-46.4% in TD2, respectively, p < 0.001). The coN system integrating LNM and TD was established, and patients with stage III colon cancer were reclassified into five subgroups (coN1a, coN1b, coN2a, coN2b and coN2c). Compared with conventional N staging, the coN staging Cox model had a smaller AIC (197097.581 vs. 197358.006) and a larger C-index (0.611 vs. 0.601). The AUCs of coN staging at 3, 5 and 7 years were also greater than those of conventional N staging (0.6305, 0.6326, 0.6314 vs. 0.6186, 0.6197, 0.6160). Concomitant with the SEER cohort results, the coN staging Cox model of the Xiangya cohort also had a smaller AIC (2883.856 vs. 2906.741) and a larger C-index (0.669 vs. 0.633). Greater AUCs at 3, 5 and 7 years for coN staging were also observed in the Xiangya cohort (0.6983, 0.6774, 0.6502 vs. 0.6512, 0.6368, 0.6199). CONCLUSIONS: Not only the presence but also the number of TDs is associated with poor prognosis in stage III colon cancer. A combined N staging system integrating LNM and TD provides more accurate prognostic prediction than the latest AJCC N staging in stage III colon cancer.

Pressure increases PD-L1 expression in A549 lung adenocarcinoma cells and causes resistance to anti-ROR1 CAR T cell-mediated cytotoxicity.

Due to the abnormal vasculation and proliferation, the tumor microenvironment is hypoxic, lacking nutrients, and under high interstitial pressure. Compared to oxygen and nutrients, the effect of pressure on cancer biology remains poorly studied. Here we constructed αROR1-CAR T cells and co-cultured with A549 cells with and without elevated pressure. We then measured apoptosis and cell death by flow cytometry and luciferase activity. We also measured cytokine (IL-2, IFN-γ, and TNF-α) release by ELISA. The results show that pressure-preconditioned A549 cells are much resistant to αROR1-CAR T cell-mediated cytotoxicity. Pressure preconditioning does not appear to affect the expression of αROR1-CAR or cytokine production. However, pressure preconditioning upregulates PD-L1 expression in A549 cells and decreases cytokine release from αROR1-CAR T cells. In addition, Pembrolizumab and Cemiplimab that block PD-1::PD-L1 interaction increase the cytokine production in αROR1-CAR T cells, increase the apoptotic cell death in A549 cells, and improve the αROR1-CAR T-mediated cytotoxicity. In xenograft mice, pressure preconditioning increases tumorigenesis of A549 cells, which can be blocked by a combined therapy using Pembrolizumab and αROR1-CAR T cells. Together, our studies suggest that elevated pressure in the tumor microenvironment could blunt the T cell therapy by upregulating PD-L1 expression, which could be overcome by combining CAR T therapy with immune checkpoint inhibitors.

Regionalized coverage of the totally degloved foot by a combination of "Boat sock" style free flap and skin graft.

INTRODUCTION: To maximize the morpho-functional recovery on the totally degloved foot while not excessively introducing the technical complexity of microsurgery, we present a regionalized reconstruction, in which the highly functional subunit (weight-bearing area and ankle-around area) is covered by free skin flaps, and the less functional subunit (dorsum) by skin graft. METHODS: From June 2011 to December 2017, 10 patients who had total degloving injury on foot underwent reconstruction based on regionalized coverage. As the shape of combined flaps resemble a boat sock in high-heeled shoe, we name it as "Boat Sock" flaps. Complication like vascular compromise, partial or total flap loss, Equinus deformity and delayed plantar ulceration were documented elaborately. Secondary surgeries were also recorded. Foot function was evaluated by Maryland foot score at the last follow up. RESULTS: Twenty-one free skin flaps were used for "Boat sock" coverage on highly functional subunits. Flap dimension ranged from 19×5cm2 to 28×8cm2 (mean 151cm2). Among these flaps, one experienced partial necrosis which was treated conservatively, one experienced burn due to lack of protective sensation. Complication like Equinus deformity or delayed plantar ulceration did not occur. Secondary surgery included debulking on two cases. Mean Maryland foot score was 90.4. CONCLUSION: This regionalized coverage by "Boat Sock" flaps and skin graft could serve as a standard procedure for reconstruction of the totally degloved foot, by offering the benefits of multi-plane coverage, a well-contoured ankle, an abrasion-tolerant planta, and eclectic surgical complexities.

EPSTI1 as an immune biomarker predicts the prognosis of patients with stage III colon cancer.

Objective: The poor prognosis and heterogeneity of stage III colon cancer (CC) suggest the need for more prognostic biomarkers. The tumor microenvironment (TME) plays a crucial role in tumor progression. We aimed to explore novel immune infiltration-associated molecules that serve as potential prognostic and therapeutic targets. Methods: TME immune scores were calculated using "TMEscore" algorithm. Differentially expressed genes between the high and low TME immune score groups were identified and further investigated through a protein-protein interaction network and the Molecular Complex Detection algorithm. Cox regression, meta-analysis and immunohistochemistry were applied to identify genes significantly correlated with relapse-free survival (RFS). We estimated immune infiltration using three different algorithms (TIMER 2.0, CIBERSORTx, and TIDE). Single-cell sequencing data were processed by Seurat software. Results: Poor RFS was observed in the low TME immune score groups (log-rank P < 0.05). EPSTI1 was demonstrated to be significantly correlated with RFS (P < 0.05) in stage III CC. Meta-analysis comprising 547 patients revealed that EPSTI1 was a protective factor (HR = 0.79, 95% CI, 0.65-0. 96; P < 0.05)). More immune infiltrates were observed in the high EPSTI1 group, especially M1 macrophage and myeloid dendritic cell infiltration (P < 0.05). Conclusion: The TME immune score is positively associated with better survival outcomes. EPSTI1 could serve as a novel immune prognostic biomarker for stage III CC.

Androgen Receptors Act as a Tumor Suppressor Gene to Suppress Hepatocellular Carcinoma Cells Progression via miR-122-5p/RABL6 Signaling.

Hepatocellular carcinoma (HCC) is a malignant tumor with a high degree of malignancy and a poor prognosis. Androgen receptor (AR) has been reported to play important roles in the regulation of the progression of HCC, but the underlying mechanisms of how AR regulates HCC initiation, progression, metastasis, and chemotherapy resistance still need further study. Our study found that AR could act as a tumor suppression gene to suppress HCC cells invasion and migration capacities via miR-122-5p/RABL6 signaling, and the mechanism study further confirmed that miR-122-5p could suppress the expression of RABL6 to influence HCC cells progression by directly targeting the 3'UTR of the mRNA of RABL6. The preclinical study using an in vivo mouse model with orthotopic xenografts of HCC cells confirmed the in vitro data, and the clinical data gotten from online databases based on TCGA samples also confirmed the linkage of AR/miR-122-5p/RABL6 signaling to the HCC progression. Together, these findings suggest that AR could suppress HCC invasion and migration capacities via miR-122-5p/RABL6 signaling, and targeting this newly explored signaling may help us find new therapeutic targets for better treatment of HCC.

Comparisons of Outcomes Between Adolescent and Young Adult with Older Patients After Radical Resection of Pancreatic Ductal Adenocarcinoma by Propensity Score Matching: A Single-Center Study.

PURPOSE: Adolescent and young adult (AYA) pancreatic ductal adenocarcinoma (PDAC) occurs in patients below 40 years old. Whether AYA patients have worse outcomes compared with older patients is still controversial. The purpose of this study is to compare the outcomes of AYA patients and older patients after radical surgery for PDAC. METHODS: A single-center, retrospective, cohort study was conducted in patients who underwent radical surgery for PDAC in Xiangya Hospital Central South University from January 2007 to December 2019. The clinicopathological data and results of patients with PDAC were collected and analyzed retrospectively. They were divided into AYA group and older group based on age (<40, AYA group; ≥40, older group). Based on all the considered covariates except age, we estimated 1:2 case propensity score matching (PSM). RESULTS: A total of 1033 cases were enrolled, 46 cases (4.45%) in the AYA group. Both before and after PSM, the AYA patients have a higher preoperative CA19-9 than the older patients (P < 0.001) and (P < 0.001). Pathological results showed that AYA group had a higher microvascular invasion rate (P < 0.001 and P = 0.045) than older group. The median time of overall survival (OS) in AYA group and older group were 13 months (95% CI = 11.50-14.50) and 14 months (95% CI = 13.50-14.50), respectively. Additionally, AYA group have a worse 2-year OS rate than older group (8.70% vs 25.23%, P = 0.011 and 8.70% vs 25.00%, P = 0.023). According to the Log rank test, AYA group have a worse cumulative OS rate than older group (P = 0.002) and (P = 0.030), respectively. CONCLUSION: PDAC might be more aggressive in AYA, and the cumulative OS after radical PDAC surgery in AYA patients is worse than that in older patients.

A Ductal-Cell-Related Risk Model Integrating Single-Cell and Bulk Sequencing Data Predicts the Prognosis of Patients With Pancreatic Adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is a highly heterogeneous malignancy. Single-cell sequencing (scRNA-seq) technology enables quantitative gene expression measurements that underlie the phenotypic diversity of cells within a tumor. By integrating PDAC scRNA-seq and bulk sequencing data, we aim to extract relevant biological insights into the ductal cell features that lead to different prognoses. Firstly, differentially expressed genes (DEGs) of ductal cells between normal and tumor tissues were identified through scRNA-seq data analysis. The effect of DEGs on PDAC survival was then assessed in the bulk sequencing data. Based on these DEGs (LY6D, EPS8, DDIT4, TNFSF10, RBP4, NPY1R, MYADM, SLC12A2, SPCS3, NBPF15) affecting PDAC survival, a risk score model was developed to classify patients into high-risk and low-risk groups. The results showed that the overall survival was significantly longer in the low-risk group (p < 0.05). The model also revealed reliable predictive power in different subgroups of patients. The high-risk group had a higher tumor mutational burden (TMB) (p < 0.05), with significantly higher mutation frequencies in KRAS and ADAMTS12 (p < 0.05). Meanwhile, the high-risk group had a higher tumor stemness score (p < 0.05). However, there was no significant difference in the immune cell infiltration scores between the two groups. Lastly, drug candidates targeting risk model genes were identified, and seven compounds might act against PDAC through different mechanisms. In conclusion, we have developed a validated survival assessment model, which acted as an independent risk factor for PDAC.

Bacillus subtilis strain BS06 protects soybean roots from Fusarium oxysporum infection.

Soybean, as a major oil crop, is one of the most widely planted crops in the world. Fusarium oxysporum causes soybean root rot, leading to great economic losses to soybean planting every year globally. Chemical fungicide for controlling soybean F. oxysporum diseases may cause environmental problems and has human health risks. Biological control methods avoid these shortcomings; however, few studies have focused on biocontrol of soybean diseases caused by F. oxysporum. Aiming at this problem, we obtained biocontrol bacteria against soybean F. oxysporum by plate confrontation method. The type of the strain with the highest biocontrol activity was identified by molecular biological methods, and then its biocontrol effects were verified through greenhouse experiments. One of our isolated strain named BS06 strain had the highest activity, which was identified as Bacillus subtilis. Our study showed that BS06 strain could effectively control soybean F. oxysporum disease and significantly reduce F. oxysporum to infect soybean roots. Compared with control and carbendazim treatments, BS06 treatment had higher root biomass, plant height, leaf chlorophyll content, stem base diameter and control efficiency. Our results indicated that BS06 could effectively protect soybean root (BS06 strain might produce substances to inhibit F. oxysporum), which was potentially useful for soybean planting.

Phosphorus is more effective than nitrogen in restoring plant communities of heavy metals polluted soils.

Heavy metal pollution is widespread, and has an increasing trend in some countries and regions. It can be easily accumulated in plants, leading to plant species loss and affecting plant community composition. Artificial restoration can conserve plant diversity in contaminated soils and accelerate the recovery of polluted ecosystems. The application of nitrogen (N) and phosphorus (P) is inexpensive and convenient, which can increase the resistance of plants to adversity and promote the growth of plants in heavy metal polluted soils. In order to examine the effect of N and P nutrition on the conservation of plant community, we conducted a comparison experiment in greenhouse using soil with low N and P concentration, and set five treatments: C (soil with no heavy metals and fertilizer addition), H (soil with heavy metals addition but with no fertilizer), HN (soil with heavy metals and N addition), HP treatment(soil with heavy metals and P addition), HNP treatment (soil with heavy metals, N and P addition). Our results showed that heavy metal pollution reduced plant species by 300%, and significantly decreased plant diversity (P < 0.05). N addition increased the richness of plant species and increased the dominance of Euphorbia peplus, but had no significant effect on plant diversity and community structure, while reduced the evenness of plant species. P addition of HP and HNP treatments restored plant species richness and increased plant diversity under heavy metal pollution. The plant community structures of these two treatments were more similar to that of group C. Compared with N addition, P addition had a better performance to restoring the species composition and relative dominance of plant communities. Our results provided a guidance for the restoration of plant communities and the conservation of plant species in low N and P concentration soils with the context of heavy metal pollution.

Impervious Surfaces Alter Soil Bacterial Communities in Urban Areas: A Case Study in Beijing, China.

The rapid expansion of urbanization has caused land cover change, especially the increasing area of impervious surfaces. Such alterations have significant effects on the soil ecosystem by impeding the exchange of gasses, water, and materials between soil and the atmosphere. It is unclear whether impervious surfaces have any effects on soil bacterial diversity and community composition. In the present study, we conducted an investigation of bacterial communities across five typical land cover types, including impervious surfaces (concrete), permeable pavement (bricks with round holes), shrub coverage (Buxus megistophylla Levl.), lawns (Festuca elata Keng ex E. Alexeev), and roadside trees (Sophora japonica Linn.) in Beijing, to explore the response of bacteria to impervious surfaces. The soil bacterial communities were addressed by high-throughput sequencing of the bacterial 16S rRNA gene. We found that Proteobacteria, Actinobacteria, Acidobacteria, Bacteroidetes, Chloroflexi, and Firmicutes were the predominant phyla in urban soils. Soil from impervious surfaces presented a lower bacterial diversity, and differed greatly from other types of land cover. Soil bacterial diversity was predominantly affected by Zn, dissolved organic carbon (DOC), and soil moisture content (SMC). The composition of the bacterial community was similar under shrub coverage, roadside trees, and lawns, but different from beneath impervious surfaces and permeable pavement. Variance partitioning analysis showed that edaphic properties contributed to 12% of the bacterial community variation, heavy metal pollution explained 3.6% of the variation, and interaction between the two explained 33% of the variance. Together, our data indicate that impervious surfaces induced changes in bacterial community composition and decrease of bacterial diversity. Interactions between edaphic properties and heavy metals were here found to change the composition of the bacterial community and diversity across areas with different types of land cover, and soil properties play a more important role than heavy metals.

Urban expansion simulation and the spatio-temporal changes of ecosystem services, a case study in Atlanta Metropolitan area, USA.

Urban expansion can lead to land use changes and, hence, threatens the ecosystems. Understanding the effects of urbanization on ecosystem services (ESs) can provide scientific guidance for land use planning and the protection of ESs. We established a framework to assess the spatial distributions of ESs based on land use changes in the Atlanta Metropolitan area (AMA) from 1985 to 2012. A new comprehensive ecosystem service (CES) index was developed to reflect the comprehensive level of ESs. Associated with the influential factors, we simulated the business as usual scenario in 2030. Four alternative scenarios, including more compact growth (MCG), riparian vegetation buffer (RVB), soil conservation (SC), and combined development (CD) scenarios were developed to explore the optimal land use strategies which can enhance the ESs. The results showed that forest and wetland had the greatest decreases, while low and high intensity built-up lands had the greatest increases. The values of CES and most of ESs decreased significantly due to the sprawling expansion of built-up land. The scenario analysis revealed that the CD scenario performs best in CES value, while it performs the worst in food supply. Compared with the RVB and SC scenarios, MCG scenario is a more optimal land use strategy to enhance the ESs without at the expense of food supply. To integrate multiple ESs into land use planning and decision making, corresponding land management policies and ecological engineering measures should be implemented to enhance: (1) the water yield and water purification in urban core counties, (2) the carbon storage, habitat quality, and recreational opportunity in counties around the core area, and (3) the soil conservation and food supply in surrounding suburban counties. The land use strategies and ecological engineering measures in this study can provide references for enhancing the ESs in the AMA and other metropolitan areas.

Soil organic carbon dynamics under long-term fertilization in a black soil of China: Evidence from stable C isotopes.

Effects of different fertilizers on organic carbon (C) storage and turnover of soil fractions remains unclear. We combined soil fractionation with isotope analyses to examine soil organic carbon (SOC) dynamics after 25 years of fertilization. Five types of soil samples including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, N; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into four aggregate sizes (>2000 µm, 2000-250 µm, 250-53 µm, and <53 µm), and three density fractions: free light fraction (LF), intra-aggregate particulate organic matter (iPOM), and mineral-associated organic matter (mSOM). Physical fractionation showed the iPOM fraction of aggregates dominated C storage, averaging 76.87% of SOC storage. Overall, application of N and NPK fertilizers cannot significantly increase the SOC storage but enhanced C in mSOM of aggregates, whereas MNPK fertilizer resulted in the greatest amount of SOC storage (about 5221.5 g C m(2)) because of the enhanced SOC in LF, iPOM and mSOM of each aggregate. The SNPK fertilizer increased SOC storage in >250 µm aggregates but reduced SOC storage in <250 µm aggregates due to SOC changes in LF and iPOM.

Long-term fertilization alters chemically-separated soil organic carbon pools: Based on stable C isotope analyses.

Quantification of dynamics of soil organic carbon (SOC) pools under the influence of long-term fertilization is essential for predicting carbon (C) sequestration. We combined soil chemical fractionation with stable C isotope analyses to investigate the C dynamics of the various SOC pools after 25 years of fertilization. Five types of soil samples (0-20, 20-40 cm) including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, IN; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into recalcitrant and labile fractions, and the fractions were analysed for C content, C:N ratios, δ(13)C values, soil C and N recalcitrance indexes (RIC and RIN). Chemical fractionation showed long-term MNPK fertilization strongly increased the SOC storage in both soil layers (0-20 cm = 1492.4 gC m(2) and 20-40 cm = 1770.6 gC m(2)) because of enhanced recalcitrant C (RC) and labile C (LC). The 25 years of inorganic fertilizer treatment did not increase the SOC storage mainly because of the offsetting effects of enhanced RC and decreased LC, whereas no clear SOC increases under the SNPK fertilization resulted from the fast decay rates of soil C.