Overexpression of Reticulon 3 Enhances CNS Axon Regeneration and Functional Recovery after Traumatic Injury

CNS neurons are generally incapable of regenerating their axons after injury due to several intrinsic and extrinsic factors, including the presence of axon growth inhibitory molecules. One such potent inhibitor of CNS axon regeneration is Reticulon (RTN) 4 or Nogo-A. Here, we focused on RTN3 as its contribution to CNS axon regeneration is currently unknown. We found that RTN3 expression correlated with an axon regenerative phenotype in dorsal root ganglion neurons (DRGN) after injury to the dorsal columns, a well-characterised model of spinal cord injury. Overexpression of RTN3 promoted disinhibited DRGN neurite outgrowth in vitro and dorsal column axon regeneration/sprouting and electrophysiological, sensory and locomotor functional recovery after injury in vivo. Knockdown of protrudin, however, ablated RTN3-enhanced neurite outgrowth/axon regeneration in vitro and in vivo. Moreover, overexpression of RTN3 in a second model of CNS injury, the optic nerve crush injury model, enhanced retinal ganglion cell (RGC) survival, disinhibited neurite outgrowth in vitro and survival and axon regeneration in vivo, an effect that was also dependent on protrudin. These results demonstrate that RTN3 enhances neurite outgrowth/axon regeneration in a protrudin-dependent manner after both spinal cord and optic nerve injury

Self Consistent Simulation of C-V Characterization and Ballistic Performance of Double Gate SOI Flexible-FET Incorporating QM Effects

Capacitance-Voltage (C-V) & Ballistic Current- Voltage (I-V) characteristics of Double Gate (DG) Silicon-on- Insulator (SOI) Flexible FETs having sub 35nm dimensions are obtained by self-consistent method using coupled Schrodinger- Poisson solver taking into account the quantum mechanical effects. Although, ATLAS simulations to determine current and other short channel effects in this device have been demonstrated in recent literature, C-V & Ballistic I-V characterizations by using self-consistent method are yet to be reported. C-V characteristic of this device is investigated here with the variation of bottom gate voltage. The depletion to accumulation transition point (i.e. Threshold voltage) of the C-V curve should shift in the positive direction when the bottom gate is negatively biased and our simulation results validate this phenomenon. Ballistic performance of this device has also been studied with the variation of top gate voltage.Comment: 4 pages, ICEDSA 2012 conferenc

A Physically Based Analytical Modeling of Threshold Voltage Control for Fully-Depleted SOI Double Gate NMOS-PMOS Flexible-FET

In this work, we propose an explicit analytical equation to show the variation of top gate threshold voltage with respect to the JFET bottom gate voltage for a Flexible Threshold Voltage Field Effect Transistor (Flexible-FET) by solving 2-D Poisson's equation with appropriate boundary conditions, incorporating Young's parabolic approximation. The proposed model illustrates excellent match with the experimental results for both n-channel and p-channel 180nm Flexible-FETs. Threshold voltage variation with several important device parameters (oxide and silicon channel thickness, doping concentration) is observed which yields qualitative matching with results obtained from SILVACO simulations.Comment: 4 pages, EIT 2012-IUPUI conferenc

Study on viscosity induced contrast in ultrasound color flow imaging of carotid atherosclerosis

Efficient imaging of blood flow disturbances resulted from carotid atherosclerosis plays a vital role clinically to predict brain stroke risk. Carotid atherosclerosis and its development is closely linked with raised blood viscosity. Therefore, study of viscosity changing hemodynamic effect has importance and it might be useful for improved examination of carotid atherosclerosis incorporating the viscosity induced contrast in conventional ultrasound imaging. This work considered the design of realistic models of atherosclerotic carotid artery of different stages and solved to compute the hemodisturbances using computational fluid dynamics (CFD) by finite element method (FEM) to investigate viscosity changes effect. Ultrasound color flow image of velocities of blood have been constructed using phase shift information estimated with autocorrelation of Hilbert transformed simulated backscattered radiofrequency (RF) signals from moving blood particles. The simulated ultrasound images have been compared with CFD simulation images and identified a good match between them. The atherosclerosis stages of the models have been investigated from the estimated velocity data. It has been observed that the blood velocities increase noticeably in carotid atherosclerotic growths and velocity distribution changes with viscosity variations. It is also found importantly that the viscosity induced contrast associated to atherosclerosis is detectable in ultrasound color flow imaging. The findings of this work might be useful for better investigation of carotid atherosclerosis as well as prediction of its progression to reduce the stroke risk

Comparison of Surgical Outcomes of ventriculoperitoneal (VP) Shunt at Choudhary’s Point vs. Keen’s Point

Objectives:  The study compared the outcomes of VP shunt at Choudhary’s vs Keen’s point. Material and Methods:  A quasi-observational study was conducted on 50 patients who presented to NS-2, PINS, with the complaint of hydrocephalus. The study was conducted for 3 months from 1st November 2021 to 31th Jan 2022. Results:  Mean age was 40 years. In 25 (50%) patients, VP shunts were done through Choudhary’s point while in 25 (50%) patients VP shunts were done through Keen’s point. All patients were evaluated on day 3rd POD, 7th POD, 15th POD, and 90th POD.  All patients were improved on 3rd POD. On the 7th POD, 15 (30%) patients deteriorated and showed signs of raised ICP. In these patients, the upper end of VP shunts is again revised due to blockage. On 15th POD, the upper end of VP shunts was blocked in 3 (6%) patients and their upper end was revised. On 90th POD, 2 (4%) patients were presented with upper-end blockage, and again shunt revision was done.  VP shunts in all these patients were done through keen’s point approach. Blockage of the lower end of VP shunt occurred in 10% of patients in which 8% were operated through Keen’s point approach while resting 2% of patients were operated through Choudhary’s point approach.  Conclusion:  VP shunts through Choudhary’s point approach yield good results as compared to Keen's point approach. This site is described by professor Muhammad Anwar Choudhary, as more convenient for insertion of VP shunt

An improved non-dimensional model of wet-cooling towers

Abstract: A general non-dimensional mathematical model of cooling towers is improved by including evaporation of water. The solution still consists of adjusting the assumed straight air-saturation line to the real air-saturation data, but a new constant (H) is added as well. Two solutions are proposed and the accuracy of each method is checked against data from the literature and also compared with the original solution. The first method shows a maximum decrease of 4.4 per cent in error, whereas in the second method, the maximum error was found to be 3.3 and 6.8 per cent when the inlet air was unsaturated and saturated, respectively. Keywords: cooling tower, non-dimensional model, evaporatio

A comprehensive design and rating study of evaporative coolers and condensers. Part II. Sensitivity analysis

Abstract Sensitivity analysis can be used to identify important model parameters, in particular, normalized sensitivity coefficients; by allowing a one-on-one comparison. Regarding design of evaporative coolers, the sensitivity analysis shows that all sensitivities are unaffected by varying the mass flow ratio and that outlet process fluid temperature is the most important factor. In rating evaporative coolers, effectiveness is found to be most sensitive to the process fluid flow rate. Also, the process fluid outlet temperature is most sensitive to the process fluid inlet temperature. For evaporative condensers, the normalized sensitivity coefficient values indicate that the condensing temperature is the most sensitive parameter and that these are not affected by the value of the mass flow ratio. For evaporative condenser design, it was seen that, for a 53% increase in the inlet relative humidity, the normalized sensitivity of the surface area increased 1.8 times in value and, for a 15 8C increase in the condenser temperature, the sensitivity increased by 3.5 times. The performance study of evaporative condensers show that, for a 72% increase in the inlet relative humidity, the normalized sensitivity coefficient for effectiveness increased 2.4 times and, for a 15 8C increase in the condenser temperature, it doubled in value. q 2005 Elsevier Ltd and IIR. All rights reserved. Keywords: Refrigeration; Air conditioning; Cooling tower; Evaporative condenser; Modelling; Research; Paramete