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Cephalic control of ovarian development in the black blowfly, Phormia regina (Meigen).
Transfer of Bone-Marrow-Derived Mesenchymal Stem Cells Influences Vascular Remodeling and Calcification after Balloon Injury in Hyperlipidemic Rats
Bone-marrow-derived mesenchymal stem cells (BM-MSCs) were found to markedly increase atherosclerotic lesion size. The aim of this paper was to investigate whether BM-MSCs contribute to vascular remodeling and calcification after balloon injury in hyperlipidemic rats. Labeled BM-MSCs were found in the lesion of hyperlipidemic rats after balloon injury. Comparing injury group, transferred BM-MSCs significantly triggered vascular negative remodeling, characterized by the changes of remodeling index (0.628 ± 0.0293 versus 0.544 ± 0.0217), neointimal area (0.078 ± 0.015 mm2 versus 0.098 ± 0.019 mm2), PCNA index (23.91 ± 6.59% versus 43.11 ± 5.31%), and percentage of stenosis (18.20 ± 1.09% versus 30.58 ± 1.21%). Apparent vascular calcification was detected in medial layers at 6 weeks after balloon angioplasty, which may be associated with upregulation of bone morphogenetic protein-2 (BMP-2). Our data indicated that unselected BM-MSCs transfer may induce vascular remodeling and calcification after balloon injury in hyperlipidemic rats
Semiconducting transport in PbCu(PO)O sintered from PbSO and CuP
The very recent claim on the discovery of ambient-pressure room-temperature
superconductivity in modified lead-apatite has immediately excited sensational
attention in the entire society, which is fabricated by sintering lanarkite
(Pb2SO5) and copper(I) phosphide (CuP). To verify this exciting claim, we
have successfully synthesized PbSO, CuP, and finally the modified
lead-apatite PbCu(PO)O. Detailed electrical transport and
magnetic properties of these compounds were systematically analyzed. It turns
out that PbSO is a highly insulating diamagnet with a room-temperature
resistivity of ~7.18x10 Ohm.cm and CuP is a paramagnetic metal with a
room-temperature resistivity of ~5.22x10 Ohm.cm. In contrast to the
claimed superconductivity, the resulting PbCu(PO)O
compound sintered from PbSO and CuP exhibits semiconductor-like
transport behavior with a large room-temperature resistivity of ~1.94x10
Ohm.cm although our compound shows greatly consistent x-ray diffraction
spectrum with the previously reported structure data. In addition, when a
pressed PbCu(PO)O pellet is located on top of a commercial
NdFeB magnet at room temperature, no repulsion could be felt and no
magnetic levitation was observed either. These results imply that the claim of
a room-temperature superconductor in modified lead-apatite may need more
careful re-examination, especially for the electrical transport properties.Comment: 12 pages, 13 figure
Biological analysis of the potential pathogenic mechanisms of Infectious COVID-19 and Guillain-Barré syndrome
BackgroundGuillain-Barré syndrome (GBS) is a medical condition characterized by the immune system of the body attacking the peripheral nerves, including those in the spinal nerve roots, peripheral nerves, and cranial nerves. It can cause limb weakness, abnormal sensations, and facial nerve paralysis. Some studies have reported clinical cases associated with the severe coronavirus disease 2019 (COVID-19) and GBS, but how COVID-19 affects GBS is unclear.MethodsWe utilized bioinformatics techniques to explore the potential genetic connection between COVID-19 and GBS. Differential expression of genes (DEGs) related to COVID-19 and GBS was collected from the Gene Expression Omnibus (GEO) database. By taking the intersection, we obtained shared DEGs for COVID-19 and GBS. Subsequently, we utilized bioinformatics analysis tools to analyze common DEGs, conducting functional enrichment analysis and constructing Protein–protein interaction networks (PPI), Transcription factors (TF) -gene networks, and TF-miRNA networks. Finally, we validated our findings by constructing the Receiver Operating Characteristic (ROC) curves.ResultsThis study utilizes bioinformatics tools for the first time to investigate the close genetic relationship between COVID-19 and GBS. CAMP, LTF, DEFA1B, SAMD9, GBP1, DDX60, DEFA4, and OAS3 are identified as the most significant interacting genes between COVID-19 and GBS. In addition, the signaling pathway of NOD-like receptors is believed to be essential in the link between COVID-19 and GBS
Capacity Prediction Model Based on Limited Priority Gap-Acceptance Theory at Multilane Roundabouts
Capacity is an important design parameter for roundabouts, and it is the premise of computing their delay and queue. Roundabout capacity has been studied for decades, and empirical regression model and gap-acceptance model are the two main methods to predict it. Based on gap-acceptance theory, by considering the effect of limited priority, especially the relationship between limited priority factor and critical gap, a modified model was built to predict the roundabout capacity. We then compare the results between Raff’s method and maximum likelihood estimation (MLE) method, and the MLE method was used to predict the critical gaps. Finally, the predicted capacities from different models were compared, with the observed capacity by field surveys, which verifies the performance of the proposed model
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