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Understanding the relationship between soil fungal communities and soil function is vital to establish a sustainable and ecologically friendly tea (Camellia sinensis L.) cultivation. However, there is limited research on the response of soil fungal communities to tea-fungus intercropping, particularly how it is related to soil biodiversity and fertility. Here, we assessed and compared the fungal communities using a metabarcoding technique, soil properties in three plantations (1, 2, and 5 yr of tea-Pleurotus intercropping plantations), and a 5 yr chemically fertilized monoculture plantation. We obtained a total of 3493 operational taxonomic units (OTUs) from four tea plantations. Five hundred and ninety-three fungal OTUs are shared by all plantations, and the other 471 fungal OTUs are shared by three plantations. The largest number of OTUs was recorded in 5 yr tea-Pleurotus intercropped plantations (N = 2040), followed by 2 yr (N = 2024) and then 1 yr (N = 1471), while the chemically fertilized plantation recorded 1823 OTUs. Tea-Pleurotus intercropping showed a significant effect on the increased diversity of soil fungal diversity compared with the monoculture tea cultivations. Fungal groups Basidiomycota, Ascomycota, and Mortierellomycota were the most abundant taxonomic groups recorded in all soil samples. Principal coordinate analysis revealed that fungal community composition in tea-Pleurotus intercropped plantations and monoculture tea plantations was significantly different. Besides, redundancy analysis revealed that soil nutrients significantly influence soil fungal community composition. Our results demonstrate that tea-Pleurotus intercropping may offer long-term benefits to soil biodiversity and sustainable benefits in the tea plantations.

Qiuli Xu,1,* Liang Ye,2,* Litang Huang,1,* Li Zhou,3 Xi Chen,4 Mingxiang Ye,3 Guannan Wu,3 Ping Zhan,3 Tangfeng Lv,3 Yong Song1 1Department of Respiratory and Critical Care Medicine, Affiliated Jinling Hospital, Southeast University, Sch Med, Nanjing, Jiangsu, People’s Republic of China; 2Department of Respiratory Medicine, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China; 3Department of Respiratory and Critical Care Medicine, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, People’s Republic of China; 4Department of Critical Care Medicine, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu, People’s Republic of China*These authors contributed equally to this workCorrespondence: Tangfeng LvDepartment of Respiratory and Critical Care Medicine, Affiliated Jinling Hospital, Medical School of Nanjing University, #305, East Zhongshan Road, Nanjing, People’s Republic of ChinaTel/Fax +86 25-8086-3591Email bairoushui@163.comYong SongDepartment of Respiratory and Critical Care Medicine, Affiliated Jinling Hospital, Southeast University, Sch Med, Nanjing, Jiangsu, People’s Republic of ChinaTel/Fax +86 25-8086-3591Email yong.song@nju.edu.cnPurpose: The survival time of patients with leptomeningeal metastasis (LM) of lung cancer is very short, and the clinical characteristics of LM are varied, making the clinical diagnosis difficult. At present, a positive CSF fluid (CSF) cytology result remains the gold standard for diagnosing LM in lung cancer; however, the process of collecting CSF is traumatic and far less convenient than blood collection. With the development in technology, an increasing number of studies prefer to use liquid biopsy to diagnose or predict the occurrence of the disease. Therefore, we aimed to explore whether serum exosomal miRNA can replace miRNA from CSF to identify or predict the occurrence of LM.Patients and Methods: Herein, four pairs of serum and CSF samples were collected at four different time points from a patient with LM from non-small cell lung cancer (NSCLC). Serum and CSF exosomes were extracted. Western blot (CD63, TSG101) and electron microscope analyses were used to verify exosome extraction, after which exosomal miRNA sequencing was performed. Next, exosomal miRNA from serum and CSF samples from seven patients with LM and 30 patients without LM were collected for validation.Results: Sequencing results of serum exosomal miRNA and CSF exosomal miRNA showed that there were 44 exosomal miRNAs stably co-expressed at four different time points. Then, three common miRNAs related to LM were found (hsa-miR-483-5p, hsa-miR-423-5p, and hsa-miR-342-5p). Subsequently, exosomal miRNA was extracted from serum and CSF samples from seven patients with LM and 30 patients without LM for verification, and the expression of these exosomal miRNA was detected. The results showed that miRNA-483-5p and miRNA-342-5p significantly differed in LM−/+ patients (P = 0.0142 and P = 0.0031, respectively), whereas miRNA-423-5p had no difference (P = 0.0921). Additionally, as the symptoms improved, the expression of these miRNAs decreased or remained stable.Conclusion: Serum exosomal miRNA (hsa-miR-483-5p, and hsa-miR-342-5p) may be involved in LM of lung cancer and may replace CSF to predict LM in NSCLC.Keywords: non-small cell lung cancer, leptomeningeal metastasis, exosome, miRNA, liquid biopsy

Background Immune checkpoint blockers (ICBs) improve the survival of patients with cancer, but primary or acquired drug resistance is inevitable. Intestinal microorganisms play an important role in immunotherapy and antitumor response, and antibiotic use can cause changes in intestinal microbial abundance and diversity. At present, the effects of antibiotic exposure on the anticancer activity of immunotherapy remain controversial. Methods We performed a meta-analysis of relevant studies retrieved from electronic databases to assess the effects of the time window of antibiotic exposure on the efficacy of immune checkpoint inhibitors (ICIs). In accordance with the definition of antibiotic use in different articles, the time window of antibiotic exposure was divided into three groups, namely, Groups 1 (antibiotic use within 2 months before or after ICI), 2 (antibiotic use before ICI), and 3 (antibiotic use anytime during ICI). Results After retrieval from the PubMed and the Embase databases, 39 cohorts were included. In group 1, progression-free survival [PFS; hazard ratio (HR) =1.81, 95% confidence interval (CI): 1.40-2.34] and overall survival (OS; HR =1.81, 95% CI: 1.43-2.28) were prolonged in patients without antibiotic use. In group 2, the subgroup analysis showed that antibiotic use had no effect on PFS (HR =0.90, 95% CI: 0.65-1.26) and OS (HR =1.53, 95% CI: 0.89-2.62) when the exposure window defined as 0-3 months. In Group 3, pooled results indicated that PFS (HR =0.78, 95% CI: 0.65-0.93) was prolonged in patients with antibiotic during immunotherapy, and no difference was observed in the OS data (HR =0.98, 95% CI: 0.78-1.24) between the patients with antibiotic and without antibiotic. Conclusions Antibiotic use in shortly time (within before or after 2 months) around the initiation of immunotherapy was remarkably related to the efficacy of ICIs. A different scenario could be observed that during the long-term treatment of ICIs, the effect of antibiotic exposure seems to be eliminated.

Although the combination of chemotherapy and immunotherapy is a hot topic in lung cancer, little is understood regarding the possible mechanisms behind their synergy. Moreover, safety is a major concern for clinicians while performing chemotherapy. Therefore, it is important to determine the appropriate dose and period of chemotherapy for combining it with immunotherapy, and investigate the underlying synergistic mechanism. Here, we showed that carboplatin can induce DNA damage and activate the canonical STING/TBK1/IRF3 pathway and non-canonical STING-NF-κB signaling complex. Further, low-dose carboplatin changed the "cold" tumor into a "hot" tumor via the signaling hub STING, augmenting CD8+ T-cell infiltration, increasing PD-L1 expression, and hence potentiating the anti-tumor effect of PD-1 inhibitors; importantly, there were no adverse effects. Furthermore, knocking down STING in tumor cells effectively reversed PD-L1 upregulation and STING pathway activation, and reduced the anti-tumor effect of low-dose carboplatin and carboplatin-PD-1 inhibitor combination. Our findings collectively reported a previously unexplored role of low-dose carboplatin targeting in the STING pathway and provided an economical, useful and safe option for improving the efficacy of PD-1 inhibitors in lung cancer.

What is already known on this topic? The health workforce at township hospitals in the China-Myanmar border region has played a key role in sustaining Community case management of malaria (CCMm), while few studies have investigated their performance and challenges. What is added by this report? Sustaining CCMm in the region was subject to the following major challenges: insufficient training on malaria diagnosis and testing, lacking necessary and timely treatment for patients, and risks of instability among the malaria workforce. What are the implications for public health practice? These challenges called for the national and provincial authorities to provide regular trainings and intensive supervision to strengthen malaria diagnosis and treatment capacity in the region and to set up incentive mechanisms and individual career development paths to sustain the workforce.

The stimulator of interferon genes (STING) pathway is important for anticancer immune responses. However, the relative contributions of host and tumour STING in anti-programmed cell death protein 1 (anti-PD-1) inhibitor responses in non-small cell lung cancer (NSCLC) are unknown. STING expression in tumour and blood was associated with anti-PD-1 therapy in NSCLC patients; Moreover, loss of PD-1 inhibitor therapeutic potency was demonstrated in STING KO (knock out) splenocytes and STING KO mice. STING knock-down in tumour cells had no effect. STING on CD8

Interferon signaling is closely associated with clearance of viral infections as well as the development of systemic lupus erythematosus (SLE). Therefore, from a clinical perspective, it is important to identify the key regulators involved in interferon signaling pathways. In this study, we identified that RNF6, as an interferon inducible E3 ubiquitin ligase, promoted the interferon-dependent antiviral response. Knock-down of RNF6 greatly attenuated expression of ISGs and the transcriptional activity of ISRE. Specifically, increased RNF6 expression in myeloid cells of patients with SLE correlated with high expression of ISGs. Our results uncover RNF6 as a positive mediator in the antiviral immune responses and suggest that RNF6 may contribute to predict interferon signaling in SLE.

Background China has increasingly emerged as an important player in global health. However, compared to developed countries, China still lacks a sufficient health workforce for global health engagement with the necessary competencies required. The world has recognized that to solve global health issues, the role of China needs to be strengthened. The priorities for the deployment of the Chinese workforce in global health remain unclear. This study aims to identify the priorities of the deployment of Chinese global health workforce by exploring the core competencies for Chinese global health workforce, factors influencing the deployment and the approach of deployment. Methods Quantitative descriptive statistical analysis was applied to analyze the quantitative data. A total of 148 key respondents from 10 provinces in China conducting global health projects over the last 3 years were selected as the study subjects. A structured questionnaire was developed to collect the data on four aspects, including general information, core competencies, factors influencing deployment, and mode of deployment. The questionnaire was distributed to the respondents through an online survey. All original data were exported to Microsoft Excel 2010 to calculate the frequencies and percentages of each option. A descriptive analysis was carried out of the priorities of deployment of the Chinese global health workforce. Results More than half of the respondents (51.4%, 76/148) regarded “communication” as the most important competency of the Chinese global health workforce, while a large proportion of participants from Chinese embassies (50.0%, 6/12) and international organizations (75.0%, 12/16) believed that “professional skills” were paramount. In addition, 58.1% (86/148) of the participants agreed that incentive factors (salary, professional position, etc.) were the main factors that influenced deployment, whereas 75% (12/16) of participants from international organizations emphasized “security” as the most important determinant. In addition, 60.8% (90/148) of the participants thought that the deployment of staff should be based on the needs of the global health project implementation. Conclusions This study highlights the deployment priorities of the Chinese global health workforce, including strengthening communication and professional skills, focusing on personal security and incentives, and catering to the project implementation. This study also highlights the importance of Chinese agencies in developing global health mindsets through global health practices and proactive integration within the global community.

The lung immune prognostic index (LIPI) has been shown to be an important prognostic marker for various tumors. However, the prognostic value of LIPI among non-small cell lung cancer (NSCLC) patients treated with systemic therapy remains controversial. We aimed to evaluate survival status according to LIPI among NSCLC patients receiving different forms of systemic therapy at our institution. We also performed a meta-analysis of articles from PubMed and Embase to illustrate this question. For our cohort, we found that good LIPI was associated with better overall survival (OS) among 91 patients on immunotherapy, 329 patients on targeted therapy, and 570 patients on chemotherapy. For the meta-analysis, a total of eight studies with 8,721 patients were included. Pooled results showed that a higher LIPI (those with 1 or 2 factors) was associated with poor overall progression-free survival (PFS) (hazard ratio [HR], 1.57; 95% confidence interval [CI], 1.45−1.71) and OS (HR, 2.01; 95% CI, 1.75−2.31). Subgroup analyses showed that a higher LIPI was related to poor survival among patients prescribed different systemic therapies: immunotherapy (OS HR, 2.50; 95% CI, 1.99–3.13; PFS HR, 1.77; 95% CI, 1.56–2.01), chemotherapy (OS HR, 1.58; 95% CI, 1.34–1.86; PFS HR, 1.38; 95% CI, 1.23–1.55), and targeted therapy (OS HR; 2.15, 95% CI, 1.57–2.96; PFS HR, 1.60; 95% CI, 1.25–2.06). The study shows that the LIPI is a clinically significant prognostic factor for NSCLC patients receiving systemic therapy.Systematic Review Registrationhttps://www.crd.york.ac.uk/PROSPERO/, identifier CRD420209009.

Although anti-PD-1 inhibitors exhibit impressive clinical results in non-small cell lung cancer (NSCLC) cases, a substantial percentage of patients do not respond to this treatment. Moreover, the current recommended biomarkers are not perfect. Therefore, it is essential to discover novel molecular determinants of responses to anti-PD-1 inhibitors. We performed Whole Exome Sequencing (WES) in a cohort of 33 Chinese NSCLC patients. Patients were classified into the durable clinical benefit (DCB) and no durable benefit (NDB) groups. Infiltrating CD8+ cells in the tumor microenvironment (TME) were investigated by immunohistochemistry. We also used public datasets to validate our results. In our cohort, good clinical responses to anti-PD-1 inhibitors were more pronounced in younger patients with lower Eastern Cooperative Oncology Group (ECOG) scores and only extra-pulmonary metastasis. More importantly, we identified a novel MUC19 mutation, which was significantly enriched in DCB patients (P = 0.015), and MUC19-mutated patients had a longer progression-free survival (PFS) (hazard ratio = 0.3, 95% CI 0.1–0.9; P = 0.026). Immunohistochemistry results indicated that the MUC19 mutation was associated with increased infiltration by CD8+ T cells in the TME (P = 0.0313). When combining MUC19 mutation with ECOG scores and intra-pulmonary metastasis status, patients with more positive predictors had longer PFS (P = 0.003). Furthermore, MUC19 mutation was involved in immune responses and associated with a longer PFS in the Memorial Sloan-Kettering Cancer Center (MSKCC) cohort. Collectively, we identified that MUC19 mutations were involved in immune responses, and NSCLC tumors harboring mutated MUC19 exhibited good responses to anti-PD-1 inhibitors.

BackgroundChina has increasingly emerged as an important player in global health. However, compared to the developed countries, China still lacks the sufficient human resources for global health engagement with limited necessary qualified capacity. The priorities for the deployment of Chinese workforce in global health engagement remains unclear. This study aims to identify the priorities of the deployment of Chinese global health workforce by exploring the core competencies for Chinese global health workforce, factors influencing the deployment and the approach of deployment. MethodA total of 148 key stakeholders from 10 provinces in China conducting global health program during the recent 3 years were selected as the study sample. A structured questionnaire was developed to collect the data on four aspects, including the general information, core competencies, factors influencing deployment, and the deployment way. The questionnaire was distributed to the respondents through an online survey tool. All original data was exported to Microsoft Excel 2010 to calculate the frequency and percentage of every option. The descriptive analysis was made on the priorities of deployment of Chinese global health workforce. ResultsMore than half of respondents 51.4% (76/148) regarded “communication” as the most important competency of Chinese global health workforce while a large portion of Chinese Embassies 50.0% (6/12) and international organizations 75.0% (12/16) believed that “professional skills” was the paramount. In addition, 58.1% (86/148) of the participants agreed that incentive factors (salary, professional title, etc.) are the first factors influencing the deployment, whereas, a majority of 75% (12/16) international organization stakeholders emphasized “security” as the foremost factor. Furthermore, 60.8% (90/148) thought that staff should be deployed align with the needs of global health program implementation. ConclusionThe study shows the priorities of the deployment of Chinese global health workforce, including strengthening the competency of communication and professional skills, stressing the personal security and incentives, and catering to the program implementation.

What is already known on this topic? Imported malaria cases endanger people’s health and potentially cause local re-transmission, and they may also cause economic loss on patients’ families and society as a whole. What is added by this report? This is the first report to focus on the disease burden of a case study incurred by the imported malaria. The results indicated that the median direct medical cost was 2,904.4 CNY and the median indirect cost was 242.0 CNY for a patient’s hospitalization. The economic cost was related to age, time between onset and diagnosis, and days of stay in hospital. What are the implications for public health practice? This study analyzed the main causes based on both direct and indirect economic loss of imported malaria cases to provide general information for the evaluation of the disease burden of imported malaria patients and shed light on the rational allocation of medical resources.

Although anti-PD-1 inhibitors exhibit impressive clinical results in non-small cell lung cancer (NSCLC) cases, a substantial percentage of patients do not respond to this treatment. Moreover, the current recommended biomarkers are not perfect. Therefore, it is essential to discover novel molecular determinants of responses to anti-PD-1 inhibitors. We performed Whole Exome Sequencing (WES) in a cohort of 33 Chinese NSCLC patients. Patients were classified into the durable clinical benefit (DCB) and no durable benefit (NDB) groups. Infiltrating CD8+ cells in the tumor microenvironment (TME) were investigated by immunohistochemistry. We also used public datasets to validate our results. In our cohort, good clinical responses to anti-PD-1 inhibitors were more pronounced in younger patients with lower Eastern Cooperative Oncology Group (ECOG) scores and only extra-pulmonary metastasis. More importantly, we identified a novel MUC19 mutation, which was significantly enriched in DCB patients (P = 0.015), and MUC19-mutated patients had a longer progression-free survival (PFS) (hazard ratio = 0.3, 95% CI 0.1–0.9; P = 0.026). Immunohistochemistry results indicated that the MUC19 mutation was associated with increased infiltration by CD8+ T cells in the TME (P = 0.0313). When combining MUC19 mutation with ECOG scores and intra-pulmonary metastasis status, patients with more positive predictors had longer PFS (P = 0.003). Furthermore, MUC19 mutation was involved in immune responses and associated with a longer PFS in the Memorial Sloan-Kettering Cancer Center (MSKCC) cohort. Collectively, we identified that MUC19 mutations were involved in immune responses, and NSCLC tumors harboring mutated MUC19 exhibited good responses to anti-PD-1 inhibitors.

Background: The stimulator of IFN genes (STING) signaling pathway plays an important role in anti-tumor immune responses. However, the mechanistic contribution of host and tumor STING signaling to the therapeutic efficacy of anti-PD-1 inhibitors in lung cancer remains unknown. Methods: We analyzed the association of STING with immune makers in TCGA datasets; we evaluated the efficacy of anti-PD-1 inhibitors by coculturing spleen cells with LLC cells in vitro, and inoculating wild type/STING knockdown LLC cells into the flank of wild-type/STING knockout mice in vivo. Furthermore, we measured the expression of STING by multiple immunohistochemistry and immunohistochemistry in lung cancer patients, and analyzed the relationship between expression level of STING in different cells and treatment efficacy of DCB(Durable clinical benefit : CR or PR or SD lasting longer than 6 months) and NDB(No durable clinical benefit : PD or SD that lasted ≤ 6 months) patients receiving immunotherapy. Results: Here we first demonstrated that STING signaling pathway activation was associated with better immunotherapy efficacy in lung cancer patients. Next, we identified two distinct STING expression pattern and found that STING in host cells not in tumor cells was positively correlated with infiltration of CD8+ T cells. More importantly, we demonstrated a loss of therapeutic efficacy of anti-PD-1 inhibitor in STING KO spleen cells and STING KO mice. In contrast, knock down of STING expression in tumor cells had no effect. Furthermore, expression of STING on host cells not in tumor cells was correlated with the efficacy of Anti-PD-1 inhibitors in lung cancer patients. Conclusion: Together, these findings demonstrate that STING expressed in host cells, rather than on tumor cells, plays an essential role in anti-PD-1 inhibitor therapy, suggesting that host intrinsic STING could be predictive of sensitivity to anti-PD-1 inhibitors. Citation Format: Li Zhou, Qiuli Xu, Litang Huang, Ping Zhan, mingxiang ye, Tangfeng Lv, Yong Song. Host intrinsic STING is a promising biomarkerfor predicting clinical efficacy of anti-PD-1 inhibitors in lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1686.

In [W.N. Hsieh, Intersection theorems for finite vector spaces, Discrete Math. 12 (1975) 1–16], Hsieh obtained the Erdős-Ko-Rado theorem for finite vector spaces. This paper generalizes Hsieh’s result and obtains the Erdős-Ko-Rado theorem for finite affine spaces.

In this article, the method of the constant volume burner was used to measure the solid propellant burning rate under high pressure. The burning rate formula and the heat loss rate equation of the constant volume burner method were derived, and the effects of four factors (pressure increasing rate, burning time, ignition, and burning rate) on the heat loss of the constant volume burner during operation were carried out. Furthermore, the testing reproducibility on burning rate was analyzed. It was shown that sample size precision, moles per unit mass of propellant, and heat loss were the main factors for the accuracy of the constant volume burner method. The shorter the burning time, the faster the pressure increasing rate and the burning rate; the less the heat loss, the appropriate ignition way was to reduce heat loss ignition. Moreover, for both various burning rates of propellants, the parallel error of the test results obtained by the method was low, and the reproducibility was high. The burning rates...

Pr 0.83 BaCo 1.33 Sc 0.5 O 6−δ –0.17PrCoO 3 (PBCS-0.17PCO) nano-composite material has been synthesized by a combined EDTA-citrate complexing sol–gel method, and characterized as cathode material of intermediate-temperature solid oxide fuel cell (IT-SOFC). Phase structure has been characterized by X-ray diffraction (XRD) measurement. The results indicate that the composite material is composed of two cubic perovskite phases with nano-scaled grain sizes. Thermal expansion coefficient (TEC) of the composite material was measured to be 18.4 × 10 −6 /°C at temperatures of 30–900 °C. Electrical conductivities were measured in air by DC four-electrode method, and the conductivity values increase monotonically with the higher temperatures from 100 °C up to 750 °C. Electrochemical performance of the PBCS-0.17PCO composite materials was studied by electrochemical impedance spectra (EIS) measurements using GDC-based symmetric cell. Low area specific resistance (ASR) values ranging from 0.127 Ω cm 2 at 600 °C, 0.069 Ω cm 2 at 650 °C, 0.039 Ω cm 2 at 700 °C to 0.026 Ω cm 2 at 750 °C were achieved for the composite cathode, demonstrating its promising application in IT-SOFCs.

Double-layered perovskite oxides of Sm1−xBaCo2O5+δ (S1−xBCO) with various A-site Sm3+-deficiencies (x = 0.00–0.08) were synthesized and evaluated as cathode materials of intermediate-temperature solid oxide fuel cells (IT-SOFCs). The Sm3+-deficiency content in S1−xBCO was limited up to x = 0.05, and higher content x = 0.08 caused impurity phase. S1−xBCO oxides were chemically stable with GDC electrolyte at 1050 °C and below. Introduction of Sm3+-deficiency caused decreased oxygen content and increased concentration of oxygen vacancy in S1−xBCO. Electrical conductivities of S1−xBCO decreased with increasing temperature in air, and also changed with the Sm3+-deficiency content. Electrochemical performance of S1−xBCO cathodes were characterized by impedance spectra measurement based on symmetric cells. Higher Sm3+ deficiency content has resulted in decreased area specific resistances (ASRs) and activation energy (Ea), i.e. enhanced electrochemical reaction reactivity for the S1−xBCO cathodes. Among the studied samples, the S0.95BCO (x = 0.05) oxide showed the best electrochemical performance with ASR values of 0.316 Ω cm2 at 600 °C, 0.137 Ω cm2 at 650 °C, 0.068 Ω cm2 at 700 °C and 0.038 Ω cm2 at 750 °C respectively, thus it's a promising cathode material of IT-SOFCs.

We introduce a new Hopf algebra Aq(sl2), consider the equitable presentation of the quantum group νq(sl2), and prove that the algebra νq(sl(2)) is a homomorphic image of Aq(sl2). We also give some properties of the equitable generators of νq(sl2).

Phase structure, structure stability, electrical properties and catalytic activity for oxygen reduction reaction of the Ba-deficient layered-perovskite oxides LaBa1-xCo2O5+delta (LB1-xCO, x = 0.00-0.15) have been studied to determine their viability as cathode material of intermediate-temperature solid oxide fuel cells (IT-SOFCs). LB1-xCO had tetragonal layered-perovskite structure when calcined at 850 degrees C-1050 degrees C in air but transformed into cubic structure at higher temperatures. The LB1-xCO oxide exhibited lower electrical conductivities and decreased area-specific resistances (ASRs) on the Ce0.9Gd0.1O1.95 (GDC) electrolyte with higher Ba-deficiency content. Among the samples, the LB0.90CO (x = 0.10) oxide exhibited the best electrochemical performance with ASR values of 0.118 Omega cm(2) at 600 degrees C and 0.023 Omega cm(2) at 700 degrees C respectively, similar to 40% lower than the results of the parent oxide (x = 0), demonstrating its promising application as cathode materials of IT-SOFCs. (C) 2013 Elsevier B.V. All rights reserved.

Scandium-doped PrBaCo2-xScxO6-delta(PBCS-x, x = 0.00-1.00) oxides have been evaluated as cathode materials of intermediate-temperature solid oxide fuel cells (IT-SOFCs) with respect to phase structure, oxygen content, thermal expansion behavior and electrical and electrochemical properties. The XRD results have demonstrated a phase transition in PBCS-x due to Sc3+ doping from tetragonal double-layered perovskite structure at x = 0.00 -0.20, bi-phase mixtures at x = 0.30-0.40, to cubic perovskite structure at x = 0.50-0.90. The oxygen contents (6-delta) and average valences of cobalt ions in PBCS-x decrease with the higher Sc3+ content and increasing temperatures in air. Sc3+ doping has also led to decreased thermal expansion coefficients, lowered electrical conductivities and enhanced electrochemical reaction activities for PBCS-x characterized by decreased area-specific resistances (ASRs) and smaller reaction activation energies. Among the studied samples, the PBCS-0.50 oxide with Sc3+-doping content of x = 0.50 exhibits the best electrochemical performance on Ce0.9Gd0.1O1.95 electrolyte. Its ASR values range from 0.123 Omega cm(2) at 600 degrees C to 0.022 Omega cm(2) at 750 degrees C, which are much lower than the related cathode materials. These results have demonstrated that the PBCS-0.50 oxide is a promising cathode material for IT-SOFCs. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

GdBaCo2O5+delta (GBCO)/poly (vinyl pyrrolidone) (PVP) composite nanofibers were prepared by electrospinning. Structural and morphological evolution of the GBCO/PVP fibers under calcinations at various temperatures was studied. Using 600 degrees C pre-calcined GBCO/PVP composite nanofibers, pure phase GBCO cathode with homogeneous network structure was easily fabricated on Ce0.9Gd0.1O1.95 (GDC) electrolyte. The as-prepared GBCO cathode was characterized by electrochemical impedance spectra (EIS) measurements based on a GBCO/GDC/GBCO symmetric cell. Its electrochemical performance was compared with the cathode prepared with the GBCO powders synthesized with sol-gel method. The GBCO cathode fabricated using GBCO/PVP composite fibers had area specific resistances (ASRs) of 0.53 Omega cm(2) at 600 degrees C, 0.22 Omega cm(2) at 650 degrees C, 0.10 Omega cm(2) at 700 degrees C and 0.043 Omega cm(2) at 750 degrees C respectively, which are lower than ASR results of the GBCO cathode prepared with powders. The results have demonstrated that the GBCO cathode fabricated using electrospun composite nanofibers has significantly enhanced electrochemical activities for oxygen reduction reaction, and it can serve as a promising cathode material for intermediate- temperature solid oxide fuel cell. (c) 2013 Elsevier B.V. All rights reserved.

A-site cation-ordered perovskite oxide LaBaCo 2 O 5+δ (LBCO) was synthesized and evaluated as a cathode material of intermediate-temperature solid oxide fuel cells (IT-SOFCs). LBCO was structurally stable when calcined at 850 °C in air but transformed into cation-disordered structure at 1050 °C. LBCO showed chemical compatibility with Gd 0.1 Ce 0.9 O 1.95 (GDC) electrolyte at 850 °C and 1000 °C in air. Conductivity of LBCO firstly increased slightly with higher temperature to a maximum of 470 S cm −1 at ∼250 °C and then decreased gradually with further increase in temperature. Electrochemical impedance spectra of the LBCO/GDC/LBCO symmetric cell were measured, and electrode reaction mechanism for the LBCO cathode was analyzed. The electrode polarization resistance of LBCO was mainly contributed by oxygen ionic transfer across the cathode/electrolyte interface and oxygen atom diffusion-electronic charge transfer process. Low area-specific resistances with values ranging from 0.15 Ω cm 2 at 650 °C to 0.0086 Ω cm 2 at 800 °C were obtained. These results have demonstrated that the A-site cation-ordered perovskite oxide LBCO is a promising cathode material for IT-SOFCs.

Let \( F_{q}^{(n)} \) denote the n-dimensional row vector space over the finite field \( F_{q} \) with \( n \ge 2 \). An l-partial injective linear map of \( F_{q} \) is a pair \( (V,F) \), where \( V \) is an l-dimensional subspace of \( F_{q}^{(n)} \) and \( f{:}\,V \to F_{q}^{(n)} \) is an injective linear map. Let L be the set of all partial injective linear maps of \( F_{q}^{(n)} \) containing 1. Ordered L by ordinary and reverse inclusion, two families of finite posets are obtained. This paper proves that these posets are lattices, discusses their geometricity and computes their characteristic polynomials.