209 research outputs found

    Structural and functional characteristics of soil microbial communities in response to different ecological risk levels of heavy metals

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    ObjectiveThe potential ecological risk index (RI) is the most commonly used method to assess heavy metals (HMs) contamination in soils. However, studies have focused on the response of soil microorganisms to different concentrations, whereas little is known about the responses of the microbial community structures and functions to HMs at different RI levels.MethodsHere, we conducted soil microcosms with low (L), medium (M) and high (H) RI levels, depending on the Pb and Cd concentrations, were conducted. The original soil was used as the control (CK). High-throughput sequencing, qPCR, and Biolog plate approaches were applied to investigate the microbial community structures, abundance, diversity, metabolic capacity, functional genes, and community assembly processes.ResultThe abundance and alpha diversity indices for the bacteria at different RI levels were significantly lower than those of the CK. Meanwhile, the abundance and ACE index for the fungi increased significantly with RI levels. Acidobacteria, Basidiomycota and Planctomycetes were enriched as the RI level increased. Keystone taxa and co-occurrence pattern analysis showed that rare taxa play a vital role in the stability and function of the microbial community at different RI levels. Network analysis indicates that not only did the complexity and vulnerability of microbial community decrease as risk levels increased, but that the lowest number of keystone taxa was found at the H level. However, the microbial community showed enhanced intraspecific cooperation to adapt to the HMs stress. The Biolog plate data suggested that the average well color development (AWCD) reduced significantly with RI levels in bacteria, whereas the fungal AWCD was dramatically reduced only at the H level. The functional diversity indices and gene abundance for the microorganisms at the H level were significantly lower than those the CK. In addition, microbial community assembly tended to be more stochastic with an increase in RI levels.ConclusionOur results provide new insight into the ecological impacts of HMs on the soil microbiome at different risk levels, and will aid in future risk assessments for Pb and Cd contamination

    Layer-by-Layer Assembly and Photocatalytic Activity of Titania Nanosheets on Coal Fly Ash Microspheres

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    In order to address the problem with titania distribution and recovery, series of Ti0.91O2/CFA photocatalysts (Ti0.91O2/CFA-n, n=2,4,6, and 8) were fabricated by assembling Ti0.91O2 nanosheets on coal fly ash (CFA) microspheres via the layer-by-layer assembly (LBLA) process and characterized by scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), N2-sorption, and ultraviolet-visible absorption (UV-vis) techniques. The SEM images and UV-vis spectra illustrated that Ti0.91O2 nanosheets were immobilized successfully on the CFA by the LBLA approach and changed the characteristics of CFA noticeably. The photocatalytic activity of Ti0.91O2/CFA was evaluated by the photodegradation of methylene blue (MB) under UV irradiation. The results demonstrated that Ti0.91O2/CFA-6 showed the best photocatalytic activity among the series of Ti0.91O2/CFA irradiated for 60 min, with a decoloration rate above 43%. After photocatalysis, the Ti0.91O2/CFA could be easily separated and recycled from aqueous solution and Ti0.91O2 nanosheets were still anchored on the CFA

    Exploring Parity Magnetic Effects through Experimental Simulation with Superconducting Qubits

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    We present the successful realization of four-dimensional (4D) semimetal bands featuring tensor monopoles, achieved using superconducting quantum circuits. Our experiment involves the creation of a highly tunable diamond energy diagram with four coupled transmons, and the parametric modulation of their tunable couplers, effectively mapping momentum space to parameter space. This approach enables us to establish a 4D Dirac-like Hamiltonian with fourfold degenerate points. Moreover, we manipulate the energy of tensor monopoles by introducing an additional pump microwave field, generating effective magnetic and pseudo-electric fields and simulating topological parity magnetic effects emerging from the parity anomaly. Utilizing non-adiabatic response methods, we measure the fractional second Chern number for a Dirac valley with a varying mass term, signifying a nontrivial topological phase transition connected to a 5D Yang monopole. Our work lays the foundation for further investigations into higher-dimensional topological states of matter and enriches our comprehension of topological phenomena

    Efficacy and safety of pembrolizumab as first-line treatment for advanced non-small cell lung cancer complicated with chronic obstructive pulmonary disease: protocol for a prospective, single-arm, single-center, phase II clinical trial

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    BackgroundThe first-line standard treatment option for patients with NSCLC complicated with Chronic obstructive pulmonary disease (COPD) is still unclear and relies on the treatment option of NSCLC alone. To date, a limited number of retrospective studies have explored the efficacy and safety of immunotherapy in patients with NSCLC complicated with COPD. We therefore designed this study to further explore the efficacy and safety of first-line immunotherapy in patients with NSCLC complicated with COPD.MethodsThis study was designed as a single-armed, single-center, prospective, phase II clinical study. It will include 30 advanced (stage IV) NSCLC combined with COPD primary treatment subjects. Each subject’s diagnosis will be confirmed by clinical, radiographic, pathologic, and pulmonary function evaluation. A fixed dose of 200 mg pembrolizumab will be administered by intravenous infusion on day1 every 3 weeks (Q3W). The management of stable and acute exacerbations of COPD include home oxygen therapy, and the use of conventional medications are also administered. Imaging evaluation will be performed every 6 weeks for 6 months from the first pembrolizumab dose and approximately every 12 weeks thereafter until disease progression or early withdrawal. COPD status will be evaluated every 3 months by pulmonary function, GOLD grading, mMRC score, CAT score, ABCD grouping, and AECOPD severity. The primary outcome is Progression-free survival. The secondary outcome measures include objective response rate, overall survival, rate of acute exacerbations of COPD (times/year), lung function, mMRC score, CAT score, impact of treatment on patient’s health-related quality of life, antibiotic use (including duration and classes), and adverse events associated with immune checkpoint inhibitors. Exploratory endpoint is to explore the association between COPD grade and the degree of immune cell (CD4+ T lymphocytes and CD8+ T lymphocytes) infiltration, as well as the association between COPD grade and the efficacy of immune checkpoint inhibitors.Clinical trial registrationClinicalTrials.gov, identifier NCT05578222

    Analysis on status of milk beverage consumption among the population in nine provinces of China

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    Objective This study aimed to describe the status of milk beverage consumption and the influence factors. Methods This study selected 13 953 samples by stratified multistage cluster random sampling in 2013. The study samples consisted of aged 3 and above with completed three non-consecutive 24 h dietary recalls and food frequency data. A Logistic regression was used to analyze the influence factors. Results The prevalence of milk beverage was 9.7% (1 350/13 953). The drinking frequency was 1.6% (217/13 953), 0.7% (94/13 953) and 7.4% (1 039/13 953) for whom consumed 1 or more times per day, 4 to 6 times per week, and 1 to 3 times per week, respectively. The prevalence was 8.5% (592/6 934) and 10.8% (758/7 019) for male and female, respectively. Stratified by age groups, the prevalence was the highest among 3 to 6-year-olds (35.5%, 165/465) and the lowest among 60 years and above (4.5%, 123/2 740). Urban prevalence (7.7%, 534/6 954) was lower than rural (11.7%, 816/6 999). The per capita consumption of milk beverage was 6.2 mL/d among all the participants (134.4 mL/d among consumers), and was 5.6 mL/d and 6.9 mL/d for male and female, respectively. Stratified by age groups, the consumption was the highest among 3 to 6-year-olds (35.6 mL/d) and the lowest among 60 years and above (2.6 mL/d). The consumption was lower in urban residents (3.2 mL/d) than that of rural residents (9.2 mL/d). Factors associated with the consumption of milk beverage were gender, age, occupation, urban-rural difference and region. Conclusion The prevalence and per capita consumption of milk beverage were relatively low among 3 years or above residents in China. Children and adolescents (3 to 17-year-old) are the main consumers of milk beverage

    Analysis on sugar intake from carbonated beverages aged 3 years and above of China

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    Objective To investigate sugar intake from carbonated beverages of Chinese residents. Methods Multistage stratified random cluster and probability proportionate sampling method was used, and 27 485 residents aged 3 and above were included from one urban and one rural district of 14 provinces (cities) in China. Data was collected by non-continuous 3-day and 24-hour-dietary retrospective method. The added sugar content in 132 carbonated beverages was obtained through the investigation of added sugar content in beverages, the energy provided by added sugar in carbonated beverages was calculated and compared with the total dietary energy from the nutrition and health monitoring diet of Chinese residents, and energy supply ratio of added sugar in carbonated drinks was calculated. Results In 2014, the daily intake of added sugar from carbonated beverages was 0.5 g, and the energy supply ratio was 0.11%. The mean daily intake of added sugar was 13.4 g, the median was 12.3 g, and the energy supply ratio was 2.69%. The median daily intake of carbonated beverages for males (15.3 g) was higher than that for females (10.1 g), it was higher for the urban areas (13.8 g) than that for rural areas (10.7 g), the differences were statistically significant (P0.05). In addition, the consumption of carbonated beverages in urban areas (3.02%) was higher than that in rural areas (2.01%), the difference was statistically significant (P<0.05). The energy supply ratio of carbonated beverage in 13-17 age group was 3.41%. Conclusion Adolescents are the high consumption group of carbonated drinks, so we should strengthen health education to guide reasonable consumption

    Regulatory Mechanisms of the Wnt/β-Catenin Pathway in Diabetic Cutaneous Ulcers

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    Skin ulcers are a serious complication of diabetes. Diabetic patients suffer from vascular lesions and complications such as peripheral neuritis, peripheral vascular lesions, and collagen abnormalities, which result in skin wounds that are refractory and often develop into chronic ulcers. The healing of skin ulcers requires an inflammatory reaction, wound proliferation, remodeling regulation, and control of stem cells. Studies investigating diabetic cutaneous ulcers have focused on cellular and molecular levels. Diabetes can cause nerve and blood vessel damage, and persistent high blood sugar levels can cause systemic multisite nerve damage based on peripheral neuropathy. The long-term hyperglycemia state enables the polyol glucose metabolism pathway to be activated, increasing the accumulation of toxic substances in the vascular injured nerve tissue cells. Sustained hyperglycemia leads to dysfunction of epithelial cells, leading to a decrease in pro-angiogenic signaling and nitric oxide production. In addition, due to impaired leukocyte function in hyperglycemia, immune function is impaired and the immune response at relevant sites is insufficient, making diabetic foot more difficult to heal. The Wnt/β-catenin pathway is a highly conserved signal transduction pathway involved in a variety of biological processes, such as cell proliferation, apoptosis, and differentiation. It is considered an important pathway involved in the healing of skin wounds. This article summarizes the mechanism of action of the Wnt/β-catenin pathway involved in the inflammatory responses to diabetic ulcers, wound proliferation, wound remodeling, and stem cells. The interactions between the Wnt signal pathway and other metabolic pathways are also discussed
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