950 research outputs found
A Note on the Generalization of the GEMS Approach
This paper is a supplement of our earlier work JHEP 0410 (2004)
011[gr-qc/0409107].We map the vector potential of charged black holes into GEMS
and find that its effect on the thermal spectrum is the same as that on the
black hole side, i.e., it will induce a chemical potential in the thermal
spectrum which is the same as that in the charged black holes.We also argue
that the generalization of GEMS approach to non-stationary motions is not
possible.Comment: Latex file, 10 pages, no figure; v2: minor corrections; v3: revised
with title changed, one new section added and references adde
Analysis on the Risk and Supervision of P2P Online Financing Platforms in China
Microcredit is a vital breakthrough to solve the financial problems of low-income groups and small and medium-sized enterprises, while traditional microfinance providers can only meet a small proportion of their capital needs. By using internet technology, P2P online financing extends the innovative development of microcredit with the aim of solving traditional micro-credit problems. This paper mainly explores the existing online financing operation model of P2P in China, and summarizes the relevant problems, such as low entry barriers for P2P online financing enterprises and lack of supervision, Lack of verification on the qualification of borrowers and poor management of the platform, imperfect information revealed or providing false information by platform, etc. Finally, the article put forward some suggestions concerning the healthy development for the P2P online financing platform, including the establishing entry audit system and strengthening the supervision of the P2P platform, strengthening the management of borrowers and improving the credit collection system, and strengthening the disclosure of information by platform
A preliminary study on the monitoring of mixed venous oxygen saturation through the left main bronchus
INTRODUCTION: The study sought to assess the feasibility and accuracy of measuring mixed venous oxygen saturation (SvO(2)) through the left main bronchus (SpO(2trachea)) METHODS: Twenty hybrid pigs of each sex were studied. After anesthesia, a Robertshaw double-lumen tracheal tube with a single-use pediatric pulse oximeter attached to the left lateral surface was introduced toward the left main bronchus of the pig by means of a fibrobronchoscope. Measurements of SpO(2trachea )and oxygen saturation from pulmonary artery samples (SvO(2blood)) were performed with an intracuff pressure of 0 to 60 cmH(2)O. After equilibration, hemorrhagic shock was induced in these pigs by bleeding to a mean arterial blood pressure of 40 mmHg. With the intracuff pressure maintained at 60 cmH(2)O, SpO(2trachea )and SvO(2blood )were obtained respectively during the pre-shock period, immediately after the onset of shock, 15 and 30 minutes after shock, and 15, 30, and 60 minutes after resuscitation. RESULTS: SpO(2trachea )was the same as SvO(2blood )at an intracuff pressure of 10, 20, 40, and 60 cmH(2)O, but was reduced when the intracuff pressure was zero (p < 0.001 compared with SvO(2blood)) in hemodynamically stable states. Changes of SpO(2trachea )and SvO(2blood )corresponded with varieties of cardiac output during the hemorrhagic shock period. There was a significant correlation between the two methods at different time points. CONCLUSION: Measurement of the left main bronchus SpO(2 )is feasible and provides similar readings to SvO(2blood )in hemodynamically stable or in low saturation states. Tracheal oximetry readings are not primarily derived from the tracheal mucosa. The technique merits further evaluation
Folate Deficiency Induces Neural Stem Cell Apoptosis by Increasing Homocysteine In Vitro
Cellular events for neural progenitor cells, such as proliferation and differentiation, are regulated by multiple intrinsic and extrinsic cell signals. Folate plays a central role in central nervous system development, so folate, as an extrinsic signal, may affect neural stem cell (NSC) proliferation and differentiation. In the present study, we investigated the effects of folate deficiency on the cell proliferation, cell apoptosis and homocysteine concentrations in NSCs. NSCs were isolated from fetal rats and identified as NSCs by their expression of immunoreactive nestin. Cell proliferation was quantitated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Apoptotic cells were detected and confirmed by flow cytometric analysis. We measured homocysteine concentrations in NSCs by high performance liquid chromatography and detected the expression of caspase-3 by western blot method. Folate deficiency not only decreased cell proliferation, but also increased the apoptotic rate of NSCs as demonstrated by the increased expression of early apoptotic markers such as caspase-3, compared to control group (p<0.05). Furthermore, There was a statistically significant increase in homocysteine concentration during folate deficiency in NSCs (p<0.05). These data suggest that folate affects the cell proliferation, apoptosis and homocysteine generation in NSC cells
The caudal pedunculopontine tegmental nucleus may be involved in the regulation of skeletal muscle activity by melanocortin-sympathetic pathway: a virally mediated trans-synaptic tracing study in spinally transected transgenic mice
Understanding neuroanatomical sympathetic circuitry and neuronal connections from the caudal pedunculopontine tegmental nucleus to skeletal muscle is important to the study of possible mechanisms of pedunculopontine tegmental nucleus (PPTg) and cuneiform nucleus (CnF) that are involved in the regulation of skeletal muscle activity of the sympathetic pathway. The aim of this study was to use virus PRV-614 to trace the melanocortin-sympathetic neural pathways from PPTg and CnF to a hindlimb muscle (gastrocnemius) in spinally transected MC4R-GFP transgenic mice. PRV-614 was injected into the gastrocnemius muscle after receiving a complete spinal cord transection below the L2 level. PRV-614/MC4R-GFP and PRV-614/TPH dual-labeled neurons were found in the dissipated parts of PPTg (dpPPTg), but not between the compact parts of PPTg (cpPPTg) and CnF. It is proposed that a hierarchical pathway of neurons within the caudal pedunculopontine tegmental nucleus sends projections to the RVLM, which in turn projects onto the IML sympathetic preganglionic neurons that regulate muscle blood flow through melanocortin-sympathetic signals. Our results collectively indicate that MC4Rs expressed in caudal pedunculopontine tegmental nucleus may be involved in skeletal muscle activity of melanocortin-sympathetic pathways
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