25 research outputs found
Influence of the size of clonal fragment on the nitrogen turnover processes in a bamboo ecosystem
Different sizes of clonal fragments contain various number of ramets with different spacer lengths, which strongly affects the redistribution of photosynthetic assimilates. Although clonal integration significantly affects rhizosphere processes via microbial enzymes under heterogeneous conditions, the effects of clonal fragment size (ramet number and spacer length) on rhizosphere N turnover processes remain poorly understood. Here, we sampled clonal fragments of Phyllostachys bissetii with different ramet numbers and spacer lengths to determine the relative effects of clonal integration and fragment size on rhizosphere processes and resource availability. We found that clonal integration had positive effects on the C and N availability of shaded ramets in clonal fragments with different ramet numbers, owing to the large resource storage in the fragment. However, it only promoted the dissolved organic carbon of the shaded ramets in clonal fragments with different spacer lengths. Results of regression analyses indicated that the response ratios of the soil variables of the shaded ramets first increased when the spacer length was about less than 30Ā cm and then decreased when the spacer became longer (about >30Ā cm), suggesting a costābenefit tradeoff in the fragment. The contribution of the size of clonal fragment to the soil N turnover process was higher than that of clonal integration, whereas its contribution to soil C availability had the opposite effect. These results further revealed the mechanism of the size of clonal fragment in affecting the rhizosphere processes of stressed ramets, which is critical for the adaptation of P. bissetii to stressed habitats and further bamboo ecosystem N turnover under climate change
Photoactive Layer of DSSCS Based on Natural Dyes: A Study of Experiment and Theory
Three natural dyes (Forsythia suspensa, Herba Violae, and Corn leaf) have been investigated as potential sensitizers for dye-sensitized solar cells. UV-vis absorption spectra reveal that three natural dyes mainly contain the compound of pheophytin a. Among three DSSCs, the highest photo electronic conversion efficiency Ī· is 0.96% with open circuit voltage (VOC) of 0.66āV, short circuit current density (ISCĀ ) of 1.97āmAācmā2, and fill factor (ff) of 0.74. Theoretical time-dependent density functional theory and charge difference density are used to explore the nature of excited states. Results demonstrate that the first state is an intramolecular charge transfer (ICT) state, and electron injection could occur owing to the thermodynamically driving force
Recurrent lung adenocarcinoma benefits from microwave ablation following multidisciplinary treatments: A case with long-term survival
Lung cancer has become the leading cause of cancer death all over the world. Nowadays, there is a consensus that the treatment of non-small cell lung cancer (NSCLC) prefers a combination of multidisciplinary comprehensive treatment and individualized treatment, which can significantly improve the prognosis of patients. Here, we report a female patient with recurrence-prone NSCLC. She had a decade-long disease course, during which the lesion recurred twice and finally cured with Multi-Disciplinary Treatment (MDT). An elderly female patient was admitted to the hospital after diagnosis of lung cancer, and treated with surgery and postoperative adjuvant chemotherapy. Five years later, suspicious lesions were found by computed tomography (CT) reexamination, and then confirmed tumor recurrence by puncture biopsy. Based on the genetic test results, gefitinib was used for subsequent targeted therapy, and the lesion gradually shrunk to disappear. However, the lesion appeared again two years later, after consultation the microwave ablation was adopted and the curative effect was excellent. At last, regular reexamination showed no abnormality, the patient has survived so far. The case proves the great benefit of multidisciplinary comprehensive treatment, especially microwave ablation for patient with recurrence-prone NSCLC. And the effect of systemic anti-tumor immune response induced by microwave ablation on lung cancer also needs to be further explored
Effects of forest spatial types, element compositions and forest stands on restorative potential and aesthetic preference
IntroductionAs global urbanization intensifies, the physical and mental stressors of modern life have led to the growing prevalence of suboptimal health conditions. Spending time in a forest benefits human health and well-being. In this context, based on the forest spatial types (forest interior and forest edge spaces), landscape elements (architecture, water and roads) and forest stands (coniferous, broadleaf and bamboo forests), this study investigated the effects of different forest spatial landscape characteristics on the restorative potential for college students, aesthetic preference and eye movement behavior (total fixation duration and fixation count).MethodsIn this study, a total of 60 subjects were exposed to 42 photographs depicting typical forest landscapes acquired through field studies. The Short-version Revised Restoration and Preference Scale and eye-tracking technology, were employed to study the recovery efficiency and visual attraction of forest spatial of different forest spatial types, element compositions and forest stands.Results(1) The restorative potential and aesthetic preference score of forest edge spaces were significantly higher than those of forest interior spaces. (2) The restorative potential of bamboo forests was significantly higher than those of coniferous and broadleaf forests. (3) In terms of forest interior space, the restorative potential of āforest + 1 elementā composition and āforest + 2 elementsā composition was significantly higher than that of pure forest, and the restorative potential of interior space of bamboo forest was significantly higher than those of coniferous and broadleaf forests. (4) In terms of forest edge space, the restorative potential of āforest + 2 elementsā composition was significantly higher than that of pure forest, and the restorative potential of pure forests was significantly higher than that of the āforest + 1 elementā composition. (5) The restorative potential of forest spatial landscape characteristics positively correlated with aesthetic preference and negatively correlated with total fixation duration and fixation count. These results can provide a reference for future forest landscape research, construction and management
High-Qf value and temperature stable Zn2+-Mn4+ cooperated modified cordierite-based microwave and millimeter-wave dielectric ceramics
Cordierite-based dielectric ceramics with a lower dielectric constant would have significant application potential as dielectric resonator and filter materials for future ultra-low-latency 5G/6G millimeter-wave and terahertz communication. In this article, the phase structure, microstructure and microwave dielectric properties of Mg2Al4ā2x(Mn0.5Zn0.5)2xSi5O18 (0 ā¤ x ā¤ 0.3) ceramics are studied by crystal structure refinement, scanning electron microscope (SEM), the theory of complex chemical bonds and infrared reflectance spectrum. Meanwhile, complex double-ions coordinated substitution and two-phase complex methods were used to improve its QĆf value and adjust its temperature coefficient. The QĆf values of Mg2Al4ā2x(Mn0.5Zn0.5)2xSi5O18 single-phase ceramics are increased from 45,000 [email protected] GHz (x = 0) to 150,500 [email protected] GHz (x = 0.15) by replacing Al3+ with Zn2+-Mn4+. The positive frequency temperature coefficient additive TiO2 is used to prepare the temperature stable Mg2Al3.7(Mn0.5Zn0.5)0.3Si5O18-ywt%TiO2 composite ceramic. The composite ceramic of Mg2Al3.7(Mn0.5Zn0.5)0.3Si5O18-ywt%TiO2 (8.7 wt% ā¤ y ā¤ 10.6 wt%) presents the near-zero frequency temperature coefficient at 1225 Ā°C sintering temperature: Īµr = 5.68, QĆf = 58,040 GHz, Ļf = ā3.1 ppm/Ā°C (y = 8.7 wt%) and Īµr = 5.82, QĆf = 47,020 GHz, Ļf = +2.4 ppm/Ā°C (y = 10.6 wt%). These findings demonstrate promising application prospects for 5 G and future microwave and millimeter-wave wireless communication technologies
Epidemic strain YC2014 of porcine epidemic diarrhea virus could provide piglets against homologous challenge
Effects of simulated atmospheric nitrogen deposition on the bacterial community structure and diversity of four distinct biocolonization types on stone monuments: a case study of the Leshan Giant Buddha, a world heritage site
Abstract Atmospheric nitrogen deposition may affect the biodeterioration process of stone monuments through direct and indirect pathways, but relevant studies are lacking. Therefore, taking the biologically colonized rocks around the Leshan Giant Buddha (World Heritage - Mixed Property) as the research objects, we studied the effects of multiple nitrogen addition levels (0, 9, 18, 36, 72Ā kg N hm-2 a-1; N0, N1; N2 ; N3; N4) on the bacterial community structure and soil nutrients on the surfaces of stones with four biocolonization types, including naked rock (NR), and lichen (LR), bryophyte (BS) and vascular plant (VS) colonization, to investigate the potential effect of atmospheric nitrogen deposition on the rock weathering of the Leshan Giant Buddha. The results demonstrated that nitrogen addition impacted soil carbon, nitrogen and phosphorus nutrients, as well as bacterial community structure and composition, but the responses to nitrogen input varied among different colonization types. Nitrogen fertilization promoted the accumulation of total organic carbon and total nitrogen in NR and LR, and increased the content of total phosphorus in VS. Bacterial Ī±-diversity decreased with nitrogen addition in NR but increased with nitrogen addition in VS. Nitrogen addition significantly (Rā>ā0.9, pā<ā0.01) changed the bacterial community composition in the four biocolonization types, and the changes were dominated by species replacement (contributed to 60.98%, 76.32%, 67.27% and 72.14% for bacterial diversity in NR, LR, BS and VS, respectively). Total nitrogen, dissolved organic nitrogen, dissolved organic nitrogen and total phosphorus were the most important ecological factors affecting bacterial community structure in NR, LR, BS and VS, respectively. Nitrogen addition enriched different bacterial taxa in the four biocolonization types. The results of this study provide basic data for the protection of stone monuments and the formulation of sustainable development strategies under a changing climate
Soil Bacteria and Fungi Respond Differently to Organisms Covering on Leshan Giant Buddha Body
Soil microbial communities play a key role in the functioning of terrestrial ecosystems, in particular through their interaction with above-ground plants and weathering of rocks. In this study, the chemical properties and microbial diversity of soils covered by different organisms on Leshan Giant Buddha body were analyzed. The results showed that the concentration of soil total organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP) increased significantly with the change of above-ground organisms from lichens to bryophytes and vascular plants. TOC, TN, TP, C:N, and C:P were significantly correlated with the composition of microbial community. Bacterial and fungal diversity responded differently to the change of organisms, and the diversity of bacterial communities changed significantly among different sites. The settlement of Embryogenic plants increased the Ī±-diversity indices including Sobs, Shannon, Ace and Chao indices, which were highest in sites covered with Ferns. The relative abundances of Chloroflexi, Acidobacteria, Nitrospirae and Planctomycetes increased with the order of Bryophyte, Fern, Grass and Shrub, and Cyanobacteria was opposite, with the highest in samples covered with lichens. These results improve understanding of plantāfungiābacteria interactions during the early stages of soil development, and provide a scientific basis for protection of Leshan Giant Buddha