Optomechanically induced gain using a trapped interacting Bose-Einstein condensate.

We investigate the realization of the phenomenon of optomechanically induced gain in a hybrid optomechanical system consisting of an interacting Bose-Einstein condensate trapped inside the optical lattice of a cavity which is generated by an external coupling laser tuned to the red sideband of the cavity. It is shown that the system behaves as an optical transistor while the cavity is exposed to a weak input optical signal which can be amplified considerably in the cavity output if the system is in the unresolved sideband regime. Interestingly, the system has the capability to switch from the resolved to unresolved sideband regime by controlling the s-wave scattering frequency of atomic collisions. We show that the system gain can be enhanced considerably by controlling the s-wave scattering frequency as well as the coupling laser intensity while the system remains in the stable regime. Based on our obtained results, the input signal can be amplified more than 100 million percent in the system output which is much larger than those already reported in the previously proposed similar schemes.

Ultraslow light realization using an interacting Bose-Einstein condensate trapped in a shallow optical lattice.

In this article, we propose an experimentally feasible scheme for the ultraslow light realization based on the optomechanically induced transparency (OMIT) phenomenon using a hybrid optomechanical system consisting of a one-dimensional Bose-Einstein condensate trapped in a shallow optical lattice considering the nonlinear effect of atom-atom interaction. It is shown how the system can switch from the normal mode splitting to the OMIT regime by manipulation of the s-wave scattering frequency of atomic collisions when the cavity is pumped at a fixed rate. Then, it is shown that an ultraslow light with a time delay more than 150 ms corresponding to a group velocity about 1 mm/s is achievable by controlling the optical lattice depth as well as the strength of atom-atom interaction and the number of atoms. Importantly, such an ultraslow light is detectable in the output of the cavity since it occurs in the frequency region of coupling-probe detuning where the reflection coefficient of the cavity is maximum.

SiRNA/DOX lodeded chitosan based nanoparticles: Development, Characterization and in vitro evaluation on A549 lung cancer cell line.

High-mobility group AT-hook2 (HMGA2), involved in epithelial mesenchymal transition (EMT) process, has a pivotal role in lung cancer metastasis. Lung cancer therapy with HMGA2 suppressing small interfering RNA (siRNA) has been introduced recently while doxorubicin (DOX) has been used as a frequent cancer chemotherapy agent. Both reagents have been faced with obstacles in clinic which make them ineffective. NanoParticles (NPs) provided a platform for efficient co delivery of the anticancer drugs. The aim of this study was production and in vitro characterization of different pharmacological groups (siRNA, DOX or siRNA-DOX) of carboxymethyl dextran thrimethyl chitosan nanoparticles (CMDTMChiNPs) on cytotoxicity, gene expression, apoptosis and migration of metastatic lung cancer cell line (A-549). CMDTMChiNPs were synthesized and encapsulated with siRNA, DOX or siRNA-DOX. Then the effects of HMGA2 siRNA and DOX co delivery was assessed in A549 viability and target genes (HMGA2, Ecadherin, vimentin and MMP9) by MTT and real time PCR, respectively. In addition capability of apoptosis induction and anti-migratory features of formulated NPs were analyzed by flowcytometry and wound healing assays. SiRNA-DOX-CMDTM ChiNPs approximate size were 207±5 with poly dispersity index (PDI) and zeta potential of 0.4 and 16.3±0.3, respectively. NPs loaded with DOX and siRNA were the most efficient drug formulations in A549 cell cytotoxicity, altering of EMT markers, apoptosis induction and migration inhibition. Generally our results showed that co delivery of HMGA2 siRNA and DOX by novel designed CMDTMChiNPs is a new therapeutic approach with great potential efficiency for lung cancer treatment.

Euglycemic state reduces the incidence of critical illness polyneuropathy and duration of ventilator dependency in medical intensive care unit.

OBJECTIVE: To examine the effect of euglycemic blood glucose control with normal insulin therapy on the incidence of critical illness polyneuropathy and duration of mechanical ventilation compared to that of conventional insulin therapy in a medical ICU. BACKGROUND: Despite the criticism over increased risk of hypoglycemia, the prevention of hyperglycemia through intensive insulin therapy has recently been confirmed to reduce the critical illness polyneuropathy (CIP). METHODS: In a single blind randomized clinical trial, forty adult patients admitted to the medical ICU were randomized to either euglycemic control (80-140 mg/dL) (Group N) or conventional approach (180-200 mg/dL, Group C). Duration of mechanical ventilation and the presence of CIP were investigated. RESULTS: The mean blood glucose levels were 131.76 ± 40.15 mg/dL in group N and 169.87 ± 50.66 mg/dL in group C (p < 0.001). Patients in group N were on mechanical ventilation for significantly less time than those in group C (p = 0.04). The diagnosis of CIP was significantly more frequent in group C than in group N (p = 0.01). CONCLUSIONS: Glucose control at levels 80-140 mg/dL with normal insulin administration is likely to be associated with both reduced incidence of CIP and duration of ventilator dependency in medical ICU (Tab. 3, Ref. 24).