Sensitivity measurement of Fibre Bragg grating sensor

A practical pass-through type fibre Bragg grating (FBG) temperature sensor system have been designed, developed, simulated, and experimentally investigated. The performance of FBG was evaluated in harsh environments exposed under direct sunlight, rain, and wind. The sensor system designed directly focused with convex and hand lens. The temperature of FBG’s sensor head been measured. The broadband laser source was launched into the system using tunable laser source (TLS) and both transmission and reflection spectra of FBG sensor were measured by optical spectrum analyzer (OSA). Results shows that the Bragg wavelength shift, ΔλB increased proportionally with the temperature changes. The sensitivity of FBG were recorded at 0.0100 and 0.0132 nm °C-1 for the systems where convex and hand lens applied to the FBG’s sensor head respectively, while the sensitivity of 0.0118 nm °C-1 measured for the system without any focusing element applied

Theoretical study on slow-light generated by integrated microring resonator with wide bandwidth and high gain

We proposed a new approach to generate slow light transmission with large bandwidth and high buildup factor by using a soliton pulse propagating within integrated ring resonator circuit. The system consisted series of micron-size ring resonator fabricated by using nonlinear InGaAsP/InP material that are laterally coupled together. For convenience of analysis, optical transfer function for this model is obtained by using z-transform method. Slow light performances were modeled and discuss in this paper. Intensity buildup induced within the series of rings located at left and right sides of the system while strong nonlinear Kerr effect and mutual coupling leads to the spreading frequency bands within the device. Numerical simulation verifies that signal pulse with 45 ps relative delay time and bandwidth of 5.9 GHz (47 pm) are obtained at the communication wavelength around 1550 nm for a 100 ps signal pulse

Numerical studies of ion beam in NX2 plasma focus for different applied voltage

Plasma focus device gives simultaneous interaction between magnetic and electric field which results in exhibiting multi-radiation properties. Ion beam radiates from the system is significant for experimenting target material of interest in plasma focus research. Lee code model is used to simulate the numerical experiments on NX2-plasma focus device system using different applied voltage in the range 10 to 14 kV. The system is operating in Neon filled at an optimum pressure depending on the applied voltage used in the experiment. Results obtained are analysed and fitted with the experimental results for system validation. Good fitting on the numerical with the experimental results is obtained by incorporating mass shedding effects and current shedding factor. The range of current density obtained is in the range 1.6 × 108 to 7.3×109 Am-2whilst the maximum ion beam energy is estimated to be 156 J

Growth of tall fescue (Festuca arundinacea Schreb.) seedling sown in soil mixed with nitrogen and natural zeolite

To determine the interaction of nitrogen and natural zeolite in culture medium on the vegetative growth of tall fescue (Festuca arundinacea Schreb.) ‘Starlet’ a greenhouse experiment was conducted. A complete randomized design with factorial arrangements including two factors (nitrogen and zeolite) was employed for each treatment with four replications. Treatments of nitrogen were 0, 0.06 and 0.12 g kg-1 in the soil mixture and treatments of zeolite were 0, 10, 20 and 30 g kg-1 in the soil mixture. Application of zeolite and nitrogen had different effects on seedling height, fresh and dry weights of clippings before first, second and third mowings, chlorophyll and nitrogen content of clippings, and dry weights of roots. Adding zeolite at the rate of 30 g kg-1 and nitrogen at the rate of 0.12 g kg-1 to culture medium significantly increased the height of turf seedlings. It is concluded that zeolite could absorb and slowly release nitrogen to the culture medium

Analysis of temperature sensor in all-pass microring resonator

The temperature sensor using all-pass microrin resonator (APMRR) investigated theoretically and analyzed. An optical bright soliton is used as a probe to study the effect of applied temperature on the light behavior pass through microring waveguide. The split-step Fourier method is used to study the pulse propagation inside the APMRR. Result shows that the rise of temperature on peak amplitude ratio fit with quadratic line in temperature range of 27 oC-37 oC. . The temperature at 30 oC generate higher slope of reduction compare to temperature at 36oC. The amplitude ratio is reduced into 0.6 (-4.4370 dB) when the temperature increased as small as 1 oC. The operating range for all-pass resonator is 97 oC with amplitude reduction of -8.3975 dB

Solitonic conduction of electrotonic signals in neuronal branchlets with polarized microstructure

A model of solitonic conduction in neuronal branchlets with microstructure is presented. The application of cable theory to neurons with microstructure results in a nonlinear cable equation that is solved using a direct method to obtain analytical approximations of traveling wave solutions. It is shown that a linear superposition of two oppositely directed traveling waves demonstrate solitonic interaction: colliding waves can penetrate through each other, and continue fully intact as the exact pulses that entered the collision. These findings indicate that microstructure when polarized can sustain solitary waves that propagate at a constant velocity without attenuation or distortion in the absence of synaptic transmission. Solitonic conduction in a neuronal branchlet arising from polarizability of its microstructure is a novel signaling mode of electrotonic signals in thin processes (<0.5 μm diameter)

Evaluation of the glycemic effect of methotrexate in psoriatic arthritis patients with metabolic syndrome. a pilot study

Methotrexate (MTX) is a systemic immunosuppressant drug used for the treatment of psoriasis and psoriatic arthritis. Previous studies demonstrated a potential association between psoriasis and diabetes mellitus, obesity, atherosclerosis, hypertension, eventuating into metabolic syndrome. This study aimed at exploring the glycemic effects of MTX in psoriatic arthritis (PsA) patients. In this prospective cross-sectional study, 27 patients with PsA were evaluated. The status of PsA and presence of accompanying metabolic syndrome was determined by standard criteria and indices. Blood indicators including HbA1c, erythrocyte sedimentation rate, fasting blood sugar, total cholesterol, high-density lipoprotein, triglycerides, and C-reactive protein were examined before and 12 weeks after MTX therapy. There were no significant changes between HbA1c levels before and after MTX therapy in both genders (men: P=0.131, women: P=0.803). In addition, HbA1c levels in PsA patients with metabolic syndrome were not different before and after treatment (P=0.250). Finally, HbA1c levels did not change in PsA patients without metabolic syndrome before and after therapy (P=0.506). MTX in PsA patients does not appear to have hyperglycaemic effects in the short-term and can be safely used in patients with metabolic syndrome and diabete

Myosin5a tail associates directly with Rab3A-containing compartments in neurons

Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of American Society for Biochemistry and Molecular Biology. The definitive version was published in Journal of Biological Chemistry, 286 (2011): 14352-14361, doi:10.1074/jbc.M110.187286.Myosin-Va (Myo5a) is a motor protein associated with synaptic vesicles (SVs) but the mechanism by which it interacts has not yet been identified. A potential class of binding partners are Rab GTPases and Rab3A is known to associate with SVs and is involved in SV trafficking. We performed experiments to determine whether Rab3A interacts with Myo5a and whether it is required for transport of neuronal vesicles. In vitro motility assays performed with axoplasm from the squid giant axon showed a requirement for a Rab GTPase in Myo5a-dependent vesicle transport. Furthermore, mouse recombinant Myo5a tail revealed that it associated with Rab3A in rat brain synaptosomal preparations in vitro and the association was confirmed by immunofluorescence imaging of primary neurons isolated from the frontal cortex of mouse brains. Synaptosomal Rab3A was retained on recombinant GST-tagged Myo5a tail affinity columns in a GTP-dependent manner. Finally, the direct interaction of Myo5a and Rab3A was determined by sedimentation v e l o c i t y analytical ultracentrifugation using recombinant mouse Myo5a tail and human Rab3A. When both proteins were incubated in the presence of 1 mM GTPγS, Myo5a tail and Rab3A formed a complex and a direct interaction was observed. Further analysis revealed that GTP-bound Rab3A interacts with both the monomeric and dimeric species of the Myo5a tail. However, the interaction between Myo5a tail and nucleotidefree Rab3A did not occur. Thus, our results show that Myo5a and Rab3A are direct binding partners and interact on SVs and that the Myo5a/Rab3A complex is involved in transport of neuronal vesicles