Systemic Chemical Desensitization of Peptidergic Sensory Neurons with Resiniferatoxin Inhibits Experimental Periodontitis

Background and objective: The immune system is an important player in the pathophysiology of periodontitis. The brain controls immune responses via neural and hormonal pathways, and brain-neuro-endocrine dysregulation may be a central determinant for pathogenesis. Our current knowledge also emphasizes the central role of sensory nerves. In line with this, we wanted to investigate how desensitization of peptidergic sensory neurons influences the progression of ligatureinduced periodontitis, and, furthermore, how selected cytokine and stress hormone responses to Gram-negative bacterial lipopolysaccharide (LPS) stimulation are affected. Material and methods: Resiniferatoxin (RTX; 50 μg/kg) or vehicle was injected subcutaneously on days 1, 2, and 3 in stress high responding and periodontitis-susceptible Fischer 344 rats. Periodontitis was induced 2 days thereafter. Progression of the disease was assessed after the ligatures had been in place for 20 days. Two h before decapitation all rats received LPS (150 μg/kg i.p.) to induce a robust immune and stress response. Results: Desensitization with RTX significantly reduced bone loss as measured by digital X-rays. LPS provoked a significantly higher increase in serum levels of the pro-inflammatory cytokine tumour necrosis factor (TNF)-, but lower serum levels of the anti-inflammatory cytokine interleukin (IL)-10 and the stress hormone corticosterone. Conclusions: In this model RTX-induced chemical desensitization of sensory peptidergic neurons attenuated ligatureinduced periodontitis and promoted a shift towards stronger pro-inflammatory cytokine and weaker stress hormone responses to LPS. The results may partly be explained by the attenuated transmission of immuno-inflammatory signals to the brain. In turn, this may weaken the anti-inflammatory brain-derived pathways

Commissioning A New Multiphase Pump Visualization Test Rig To Investigate The Internal Flow Field And Its Connection With Pump Performance

LecturePumps with helico-axial impellers are used to boost mixtures of gas and liquid, for instance in subsea production of unprocessed oil and gas. Experimental data is essential to fully understand and characterize the internal flow, as well as for validation and improvement of numerical modeling techniques. Here we describe the commissioning of a test rig that enables visualization and measurements of the pump’s internal flow field. The test rig’s pump unit design contains three impeller stages that are 50 percent downscaled relative to a full-scale version previously tested.A reduction in nondimensional head, flow and efficiency relative to the full-scale pump can be attributed to lower Reynolds numbersand an increased relative impeller tip clearance. The tested head curves on single phase water exhibit a transition where the negative slope is replaced by a flat curve when reducing the volumetric flow rate below a certain value. Despite the downscaling, this change in slope occurs at the same relative flow rate as for the full-scale pump. This suggests that the test rig can be used to replicate the characteristics of the full-scale performance and flow field in pumps with helico-axial impellers. Varying the impeller tip clearance allowed for an estimate of pump head with the equivalent clearance as for the full-scale geometry. A Morrison number of 0.03 could then be established for the pump.The impeller tip leakage flow and two recirculation zones in the diffuser channels were identified in a preliminary view of the internal flow field at two percent gas volume fraction and part-load operating conditions. Operation at low relative flow rates and high gas volume fractions led to system surge and slugging in the flow loop. Increasing the inlet pressure and temperature significantly improvedthe situation, allowing stable operation at lower relative flow rates. Modifications to avoid gas coalescence through the pump inlet could also further widen the operational envelope at high gas volume fraction

Fast Addition using Balanced Ternary Counters Designed with CMOS Semi-Floating Gate Devices

This paper presents ternary counters using balanced ternary notation. The balanced ternary counters can replace binary full adders or counters in fast adder structures. The circuits use recharged CMOS semi-floating gate (RSFG) devices. By using balanced ternary notation, it is possible to build balanced ternary addition circuits, which can add both negative and positive operands, by using the same adder blocks. The circuit operates at a clock frequency of 1 Ghz. The supply voltage 1.0 Volt.

Fault Tolerant CMOS Logic Using Ternary Gates

In this paper we present fault tolerant CMOS logic using redundancy and ternary signals. The ternary gates are implemented using recharge logic which can be exploited in binary and multiple-valued logic (MVL). Signals are processed through capacitors in such a way that the logic operation of a gate is independent of the DC voltage applied on the inputs. By combining signals through capacitors stuck on/stuck off and stuck at faults are not destructive when redundancy is applied. Simulated data for 130nm and 0.35µm CMOS processes are given.