Vertical distribution of Fe, P and correlation with organic carbon in coastal sediments of Yellow Sea, Eastern China

The coastal zone is considered as a major carbon pool. Iron minerals and phosphates are vital factors affecting the amounts and occurrence of total organic carbon (TOC) in sediments. However, coupling mechanisms of iron (Fe) and phosphorous (P) in the source-sink transition of TOC in coastal sediments is poorly understood. This study characterized the distribution of Fe, P and TOC contents of three independent 170 cm sediment cores sampled from a coastal aquaculture area in the eastern Jiangsu Province, and quantified the correlations among Fe, P, median grain diameter (Dx(50)), and TOC. The results showed total phosphorus (TP) content ranges in a scope of 337.4-578.0 mg/kg, and many depths recorded moderate P eutrophication. Inorganic phosphorus (DA + IP) and biogenic apatite were the primary components of TP, accounting for 25.19–55.00 and 26.71–49.62%, respectively. The Fe contents varied from 987.9 mg/kg to 2900.7 mg/kg, in which oxidized iron (Feox) accounted for about 62.2–79.4%. In the vertical profile, the TOC was positively correlated with the contents of low-crystallinity Fe-bearing carbonates (Fecarb), high crystallinity pyrite (FePy), iron-bound phosphorus (PCDB), manganeses (Mn), and nitrogen (N), while it was negatively correlated with DA + IP, organic phosphorus (OP), and Dx(50). Based on the the partial least squares (PLS) model, we proposed that the higher FePy, Mn, magnetite (FeMag), Fecarb, PCDB, amorphous exchangeable Fe (Ex-Fe), and authigenic apatite phosphorus (Bio-P) in sediments represent the high capacity for TOC sink, whereas, higher DA + IP, and OP indicate a TOC conversion to the source. The non-siginificat indication of Feox on TOC source-sink is due to its surplus and strong reactivity relative to TOC content. These revealed correlations provide a theoretical reference for understanding and regulating the burial rate and storage of TOC by changing the input of Fe minerals and P components into coastal sediments

Inferring the diagnostic potential of 18F-FDG-PET/CT in post-renal transplantation from a unique case harboring multiple rare complications

Renal transplantation is undoubtedly an effective treatment for patients with end-stage renal disease, but it is certainly not a cure. Patients require lifelong immunosuppression to maintain optimal allograft function, and post-operative risk complications such as cancer in the transplant recipient cannot be ignored. Besides, infection is a silent complication that follows transplantation. Relatedly, herein, we present a report of a 40-year-old patient who underwent renal transplantation and promptly developed a diffuse large B-cell tumor in the liver and Aspergillus infection in the trachea. In addition, an inflammatory necrotizing granuloma was also observed in the muscles. Of importance, we also described the potential of 18F-FDG-PET/CT, which was instrumental in monitoring and evaluating these relevant post-operative complications in this rare case

HIV-1 Membrane-Proximal External Region Fused to Diphtheria Toxin Domain-A Elicits 4E10-Like Antibodies in Mice.

The production of broadly neutralizing antibodies (bNAbs) is a major goal in the development of an HIV-1 vaccine. The membrane-proximal external region (MPER) of gp41, which plays a critical role in the virus membrane fusion process, is highly conserved and targeted by bNAbs 2F5, 4E10, and 10E8. As such, MPER could be a promising epitope for vaccine design. In this study, diphtheria toxin domain A (CRM197, amino acids 1-191) was used as a scaffold to display the 2F5 and 4E10 epitopes of MPER, named CRM197-A-2F5 and CRM197-A-4E10. Modest neutralizing activities were detected against HIV-1 clade B and D viruses in the sera from mice immunized with CRM197-A-4E10. Monoclonal antibodies raised from CRM197-A-4E10 could neutralize several HIV-1 strains, and epitope-mapping analysis indicated that some antibodies recognized the same amino acids as 4E10. Collectively, we show that 4E10-like antibodies can be induced by displaying MPER epitopes using an appropriate scaffold. These results provide insights for HIV-1 MPER-based immunogens design

Morphological diversity of single neurons in molecularly defined cell types.

Dendritic and axonal morphology reflects the input and output of neurons and is a defining feature of neuronal types1,2, yet our knowledge of its diversity remains limited. Here, to systematically examine complete single-neuron morphologies on a brain-wide scale, we established a pipeline encompassing sparse labelling, whole-brain imaging, reconstruction, registration and analysis. We fully reconstructed 1,741 neurons from cortex, claustrum, thalamus, striatum and other brain regions in mice. We identified 11 major projection neuron types with distinct morphological features and corresponding transcriptomic identities. Extensive projectional diversity was found within each of these major types, on the basis of which some types were clustered into more refined subtypes. This diversity follows a set of generalizable principles that govern long-range axonal projections at different levels, including molecular correspondence, divergent or convergent projection, axon termination pattern, regional specificity, topography, and individual cell variability. Although clear concordance with transcriptomic profiles is evident at the level of major projection type, fine-grained morphological diversity often does not readily correlate with transcriptomic subtypes derived from unsupervised clustering, highlighting the need for single-cell cross-modality studies. Overall, our study demonstrates the crucial need for quantitative description of complete single-cell anatomy in cell-type classification, as single-cell morphological diversity reveals a plethora of ways in which different cell types and their individual members may contribute to the configuration and function of their respective circuits

Behaviour of expansion tubes under impact load: Deformation mode and mechanical response

The expansion tube is a promising energy absorption structure in spacecraft and airplanes, where it is often exposed to impact stress. Despite prior studies on the deformation mode of expansion tubes have been conducted, the majority of them have relied on quasi-static load. This research has utilized theoretical, computational, and experimental approaches to concentrate on the behaviors of expansion tubes exposed to dynamic impacts. The experimental results show that the strain-rate effect and the downward velocity discrepancy could even cause the deformation mode transition of the expansion tube. The dynamic theoretical model of steady-state expansion force is derived and used to predict the normalized compressive force. A normalized compressive force more than 0.85 would promote buckling deformation of the expansion tube. The normalized compressive force is then used to predict the deformation mode diagrams of the expansion tube for a range of geometric parameters; this analysis reveals that the semi-angle, expansion rate, and radius/wall-thickness of the tube all play a role in determining the deformation mode, while the effect of length/radius is less evident. The expansion tube's buckling resistance is enhanced by the parent material's strain rate sensitivity and diminished by the strain hardening effect

The hand-lateralization of spatial associations in working memory and long-term memory

Spatial-numerical and spatial-positional associations have been well documented in the domains of numerical cognition and working memory, respectively. However, such associations are typically calculated by directly comparing (e.g., subtracting) left- versus right-hand responses; it remains an open question whether such associations reside in each hand individually, or are exclusively localised in one of the two hands. We conducted six experiments to investigate the hand-lateralization of both spatial-numerical and spatial-positional associations. All experiments revealed that the spatial associations stemmed from left-hand responses, irrespective of the handedness of the subjects, but with the exception of the magnitude comparison task (Experiments 5 and 6). We propose that the hemispheric lateralization of the tasks in combination with the task-relevance of spatial associations can explain this pattern. More generally, we suggest that the contributions of left and right hands require more attention in spatial-numerical and spatial-positional research

Membrane binding of the insertion sequence of Proteus vulgaris L-amino acid deaminase stabilizes protein structure and increases catalytic activity

Abstract Proteus vulgaris L-amino acid deaminase (pvLAAD) belongs to a class of bacterial membrane-bound LAADs mainly express in genus Proteus, Providencia and Morganella. These LAADs employ a non-cleavable N-terminal twin-arginine translocation (Tat) peptide to transport across membrane and bind to bacterial surface. Recent studies revealed that a hydrophobic insertion sequence (INS) in these LAADs also interacts with bacterial membrane. However, the functional significance of INS-membrane interaction is not clear. In this study, we made site-directed mutagenesis on the surface-exposed hydrophobic residues of pvLAAD INS, and we found that these mutations impaired the INS-membrane interaction but did not affect pvLAAD activity in the solution. We further found that when cell membrane is present, the catalytic activity can be increased by 8~10 folds for wild-type but not INS-mutated pvLAAD, indicating that the INS-membrane interaction is necessary for increasing activity of pvLAAD. Molecular dynamic (MD) simulations suggested that INS is flexible in the solution, and its conformational dynamics could lead to substrate channel distortion. Circular dichroism (CD) spectroscopy experiments indicated that bacterial membrane was able to maintain the conformation of INS. Our study suggests the function of the membrane binding of INS is to stabilize pvLAAD structure and increase its catalytic activity

DataSheet_1_Vertical distribution of Fe, P and correlation with organic carbon in coastal sediments of Yellow Sea, Eastern China.pdf

The coastal zone is considered as a major carbon pool. Iron minerals and phosphates are vital factors affecting the amounts and occurrence of total organic carbon (TOC) in sediments. However, coupling mechanisms of iron (Fe) and phosphorous (P) in the source-sink transition of TOC in coastal sediments is poorly understood. This study characterized the distribution of Fe, P and TOC contents of three independent 170 cm sediment cores sampled from a coastal aquaculture area in the eastern Jiangsu Province, and quantified the correlations among Fe, P, median grain diameter (Dx(50)), and TOC. The results showed total phosphorus (TP) content ranges in a scope of 337.4-578.0 mg/kg, and many depths recorded moderate P eutrophication. Inorganic phosphorus (DA + IP) and biogenic apatite were the primary components of TP, accounting for 25.19–55.00 and 26.71–49.62%, respectively. The Fe contents varied from 987.9 mg/kg to 2900.7 mg/kg, in which oxidized iron (Feox) accounted for about 62.2–79.4%. In the vertical profile, the TOC was positively correlated with the contents of low-crystallinity Fe-bearing carbonates (Fecarb), high crystallinity pyrite (FePy), iron-bound phosphorus (PCDB), manganeses (Mn), and nitrogen (N), while it was negatively correlated with DA + IP, organic phosphorus (OP), and Dx(50). Based on the the partial least squares (PLS) model, we proposed that the higher FePy, Mn, magnetite (FeMag), Fecarb, PCDB, amorphous exchangeable Fe (Ex-Fe), and authigenic apatite phosphorus (Bio-P) in sediments represent the high capacity for TOC sink, whereas, higher DA + IP, and OP indicate a TOC conversion to the source. The non-siginificat indication of Feox on TOC source-sink is due to its surplus and strong reactivity relative to TOC content. These revealed correlations provide a theoretical reference for understanding and regulating the burial rate and storage of TOC by changing the input of Fe minerals and P components into coastal sediments.</p

Reversible bipolar thermopower of ionic thermoelectric polymer composite for cyclic energy generation

Generating continuous power by ionic thermoelectric material modules remains challenging. Here, the authors find the ionic thermoelectric material exhibiting bipolar thermopower property by manipulating the interactions between ions and electrodes