Soil respiration components and their temperature sensitivity under chemical fertilizer and compost application: the role of nitrogen supply and compost substrate quality

Understanding autotrophic (Ra) and heterotrophic (Rh) components of soil respiration (Rs) and their temperature sensitivity (Q10) is critical for predicting soil carbon (C) cycle and its feedback to climate change. In agricultural systems, these processes can be considerably altered by chemical fertilizer and compost application due to changes in nitrogen (N) supply and substrate quality (decomposability). We conducted a field experiment including control, urea and four compost treatments. Ra and Rh were separated using the root exclusion method. Composts were characterized by chemical analyses, 13C solid‐state NMR, and lignin monomers. Annual cumulative Ra, along with root biomass, increased with soil mineral N, while Rh was suppressed by excessive N supply. Thus, Ra was stimulated but Rh was decreased by urea alone application. Annual Rh was increased by application of compost, especially that containing most lignin vanillyl and syringyl units, O‐alkyl C, di‐O‐alkyl C, and manganese. However, during the initial period, Rh was most effectively stimulated by the compost containing most carbohydrates, lignin cinnamyl units, phenolic C and calcium. Ra was mediated by N release from compost decomposition, and thus exhibited similar responses to compost quality as Rh. The Rh Q10 was reduced while Ra Q10 was increased by chemical fertilizer and compost application. Moreover, the Rh Q10 negatively related to soil mineral N supply and compost indicators referring to high substrate quality. Overall, our results suggest that N supply and substrate quality played an important role in regulating soil C flux and its response to climate warming

Dynamic effects of the Nuss procedure on the spine in asymmetric pectus excavatum

ObjectiveThis study aimed to elucidate dynamic effects of the Nuss procedure on the spine in the treatment of patients with pectus excavatum with asymmetric thoraces.MethodsTwenty-five patients with pectus excavatum who underwent the Nuss procedure were categorized into 4 groups by preoperative morphology of the spine and thoracic asymmetry. In group 1 (n = 8), the right side of the thorax was concave and the spine bowed to the right. In group 2 (n = 4), the right side of the thorax was concave and the spine bowed to the left. In group 3 (n = 5), the left side of the thorax was concave and the spine bowed to the right. In group 4 (n = 8), the left side of the thorax was concave and the spine bowed to the left. With computed tomographic data, finite-element models were produced to simulate each patient's thorax. Thereafter, dynamic response patterns of the spine to the Nuss procedure were examined. Validity of these biomechanical findings was verified by referring to clinical outcomes.ResultsIn group 1 and group 4 models, deformed spines were straightened; in group 2 and group 3 models, spinal bowing increased. These biomechanical findings were compatible with clinical evaluations.ConclusionsPerformance of the Nuss procedure for asymmetric pectus excavatum exerts dynamic influence on the spine. Response patterns of the spine are predictable from morphologic relationships between the asymmetric patterns of the anterior thoracic wall and the spine

Soil respiration components and their temperature sensitivity under chemical fertilizer and compost application: the role of nitrogen supply and compost substrate quality

Understanding autotrophic (Ra) and heterotrophic (Rh) components of soil respiration (Rs) and their temperature sensitivity (Q10) is critical for predicting soil carbon (C) cycle and its feedback to climate change. In agricultural systems, these processes can be considerably altered by chemical fertilizer and compost application due to changes in nitrogen (N) supply and substrate quality (decomposability). We conducted a field experiment including control, urea and four compost treatments. Ra and Rh were separated using the root exclusion method. Composts were characterized by chemical analyses, 13C solid‐state NMR, and lignin monomers. Annual cumulative Ra, along with root biomass, increased with soil mineral N, while Rh was suppressed by excessive N supply. Thus, Ra was stimulated but Rh was decreased by urea alone application. Annual Rh was increased by application of compost, especially that containing most lignin vanillyl and syringyl units, O‐alkyl C, di‐O‐alkyl C, and manganese. However, during the initial period, Rh was most effectively stimulated by the compost containing most carbohydrates, lignin cinnamyl units, phenolic C and calcium. Ra was mediated by N release from compost decomposition, and thus exhibited similar responses to compost quality as Rh. The Rh Q10 was reduced while Ra Q10 was increased by chemical fertilizer and compost application. Moreover, the Rh Q10 negatively related to soil mineral N supply and compost indicators referring to high substrate quality. Overall, our results suggest that N supply and substrate quality played an important role in regulating soil C flux and its response to climate warming.This is a manuscript of an article published as Chen, Zengming, Yehong Xu, Michael J. Castellano, Sébastien Fontaine, Weijin Wang, and Weixin Ding. "Soil respiration components and their temperature sensitivity under chemical fertilizer and compost application: the role of nitrogen supply and compost substrate quality." Journal of Geophysical Research: Biogeosciences (2019). doi: 10.1029/2018JG004771. Posted with permission.</p

Three-Dimensional Copper Foil-Powder Sintering Current Collector for a Silicon-Based Anode Lithium-Ion Battery

In this work, we propose a facile method for manufacturing a three-dimensional copper foil-powder sintering current collector (CFSCC) for a silicon-based anode lithium-ion battery. We found that the CFSCC is suitable as a silicon-based paste electrode, and the paste-like electrodes are commonly used in industrial production. Compared with flat current collectors, the CFSCC better constrained the silicon volume change during the charging-discharging process. The capacitance of electrodes with CFSCC remained as high as 92.2% of its second cycle after 40 cycles, whereas that of electrodes with a flat current collector only remained at 50%

Neurotrophic factors which direct the transdifferentiation.

<p>(A) ELISA assay showed the quantity of seven neurotrophic factors in the SC conditioned medium. There were high levels of BDNF, PDGF, NT-3 and IGF-2. The levels of NGF were relatively low, while GDNF and FGF were undetectable. (B) Phase-contrast micrographs showed that MDSCs adopted a SC-like shape upon treatment with PDGF (1000 pg/ml), NT-3 (500 pg/ml) and IGF-2 (200 pg/ml) in combination. (C) Immunocytochemisty showed that the tMDSCs highly expressed the SC marker S100 protein. (D) Flow cytometry assay demonstrated that the portion of S100, GFAP, and p75 positive cells in tMDSCs were 58.64±4.38%, 47.38±0.84% and 44.33±2.39%, while 27.89±5.98% of the tMDSCs expressed all of the three SC markers (data are mean % cells±S.E.M.). (E) Immunoblot assay showed the MDSCs expressed of S100, GFAP and p75 only after transdifferentiation. β-actin served as loading control. Right, bar graph of qualitative data in statistics. S100, GFAP and p75 protein levels were normalized to that of β-actin, shown as mean±S.E.M. **, p<0.01 vs. MDSC.</p

Isolation and Characterisation of mouse MDSCs.

<p>(A) Phase-contrast micrographs of undifferentiated PP6 cells isolated from mouse skeletal muscle. The cells had a rounded shape like stem cells. (B) Growth curve of PP6 cells showed a slow-cycling phenotype like stem cells. (C) Immunofluorescence staining showed the PP6 cells were desmin and Sca-1 positive which indicated they were MDSCs. (D) Flow cytometry assay demonstrated that 93.23±0.93% of the PP6 cells were Sca 1 positive, and 94.18±0.38% were desmin positive. 90.1±1.28% were double positive cells (data are mean % cells±S.E.M.). All experiments were repeated at least three times in triplicates.</p

Intranasal mask for protecting the respiratory tract against viral aerosols

Abstract The spread of many infectious diseases relies on aerosol transmission to the respiratory tract. Here we design an intranasal mask comprising a positively-charged thermosensitive hydrogel and cell-derived micro-sized vesicles with a specific viral receptor. We show that the positively charged hydrogel intercepts negatively charged viral aerosols, while the viral receptor on vesicles mediates the entrapment of viruses for inactivation. We demonstrate that when displaying matched viral receptors, the intranasal masks protect the nasal cavity and lung of mice from either severe acute respiratory syndrome coronavirus 2 or influenza A virus. With computerized tomography images of human nasal cavity, we further conduct computational fluid dynamics simulation and three-dimensional printing of an anatomically accurate human nasal cavity, which is connected to human lung organoids to generate a human respiratory tract model. Both simulative and experimental results support the suitability of intranasal masks in humans, as the likelihood of viral respiratory infections induced by different variant strains is dramatically reduced

Isolation and Characterisation of mouse SCs to obtain the conditioned medium.

<p>(A) Phase-contrast micrographs of SCs isolated from mouse sciatic nerve and dorsal root ganglia. The cells had typical spindle-shaped SC morphology. (B) Immunofluorescence staining demonstrated the isolated cells expressed SC marker S100 protein. (C) Flow cytometry assay showed that most of the cells were S100 (96.77±1.46%), GFAP (92.92±4.94%), and p75 (93.38±0.90%) positive, and 86.12±1.53% of the cells expressed all of the three SC markers (data are mean % cells±S.E.M.).</p