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Port site and peritoneal metastases after robot-assisted radical prostatectomy
No full textIntroduction: Port site metastasis after minimally invasive urologic surgery is a rare event despite the widespread utility of laparoscopic techniques in the management of urologic malignancies. Herein, we report a case of port site metastasis after robot-assisted radical prostatectomy. Presentation of case: A currently 77-year-old male patient, who was diagnosed with cT2c, Gleason 7 (4 + 3) prostate adenocarcinoma in our clinic back in 2009, had undergone robot-assisted radical prostatectomy elsewhere. Histopathological examination revealed pT3a, Gleason 9 (4 + 5) disease. Lymph nodes were negative, however surgical margins were positive on the right side. PSA recurred after 9 months and maximal androgen blockade was initiated. Despite antiandrogenic manipulations, PSA reached 0.83 ng/ml, 33 months postoperatively. Concurrently, we noticed a palpable anterior abdominal mass which demonstrated metabolic hyperactivity on PET scanning. Percutaneous biopsy of the lesion confirmed the presence of metastatic adenocarcinoma. PSA did not normalize after the complete excision of the metastatic focus. Repeated PET scan revealed multiple implants on the peritoneal surfaces of various organs. Discussion: Port site and peritoneal metastasis of prostate cancer after robot-assisted radical prostatectomy has not been reported so far. This peculiar dissemination pattern is most probably the result of tumor biology and perioperative factors. Conclusion: Although encountered extremely rarely, surgeons should be aware of the possibility of port site and/or peritoneal metastases after minimally invasive radical prostatectomy
Tuning of optical resonances of a microsphere with liquid crystal
No full textOptical resonances are observed in the elastic light scattering form high refractive index glass microspheres placed on a single mode optical fiber coupler and in a liquid crystal. Placing the liquid crystal on the optical fiber coupler increases the non-resonant scattering, whereas placing the liquid crystal away from the optical coupler increases the resonant scattering. Optical resonances blue and red shift due to the placement and removal of the liquid crystal
Electro-optical modulation with silicon microspheres in liquid crystal
No full textWe demonstrate electro-optical tuning and modulation of the optical resonances of a silicon microsphere placed on an optical fiber half coupler and immersed in a nematic liquid crystal. The relative refractive index between the microsphere and the liquid crystal is controlled by an applied external AC electric field. The tuning and modulation of the microsphere optical resonances is monitored with the transmission and elastic scattering signals
Multidimensional wave packet dynamics within the fluid dynamical formulation of the Schrodinger equation
No full textThis paper explores the quantum fluid dynamical (QFD) representation of the time-dependent Schrodinger equation for the motion of a wave packet in a high dimensional space. A novel alternating direction technique is utilized to single our each of the many dimensions in the QFD equations. This technique is used to solve the continuity equation for the density and the equation for the convection of the flux for the quantum particle. The ability of the present scheme to efficiently and accurately describe the dynamics of a quantum particle is demonstrated in four dimensions where analytical results are known. We also apply the technique to the photodissociation of NOCl and NO2 where the systems are reduced to two coordinates by freezing the angular variable at its equilibrium value
RACK1 is an interaction partner of ATG5 and a novel regulator of autophagy
No full textAutophagy is biological mechanism allowing recycling of long-lived proteins, abnormal protein aggregates, and damaged organelles under cellular stress conditions. Following sequestration in double-or multimembrane autophagic vesicles, the cargo is delivered to lysosomes for degradation. ATG5 is a key component of an E3-like ATG12-ATG5-ATG16 protein complex that catalyzes conjugation of the MAP1LC3 protein to lipids, thus controlling autophagic vesicle formation and expansion. Accumulating data indicate that ATG5 is a convergence point for autophagy regulation. Here, we describe the scaffold protein RACK1 (receptor activated C-kinase 1, GNB2L1) as a novel ATG5 interactor and an autophagy protein. Using several independent techniques, we showed that RACK1 interacted with ATG5. Importantly, classical autophagy inducers (starvation or mammalian target of rapamycin blockage) stimulated RACK1-ATG5 interaction. Knockdown of RACK1 or prevention of its binding to ATG5 using mutagenesis blocked autophagy activation. Therefore, the scaffold protein RACK1 is a new ATG5-interacting protein and an important and novel component of the autophagy pathways
2D hybrid meshes for direct simulation Monte Carlo solvers
No full textThe efficiency of the direct simulation Monte Carlo (DSMC) method decreases considerably if gas is not rarefied. In order to extend the application range of the DSMC method towards non-rarefied gas regimes, the computational efficiency of the DSMC method should be increased further. One of the most time consuming parts of the DSMC method is to determine which DSMC molecules are in close proximity. If this information is calculated quickly, the efficiency of the DSMC method will be increased. Although some meshless methods are proposed, mostly structured or non-structured meshes are used to obtain this information. The simplest DSMC solvers are limited with the structured meshes. In these types of solvers, molecule indexing according to the positions can be handled very fast using simple arithmetic operations. But structured meshes are geometry dependent. Complicated geometries require the use of unstructured meshes. In this case, DSMC molecules are traced cell-by-cell. Different cell-by-cell tracing techniques exist. But, these techniques require complicated trigonometric operations or search algorithms. Both techniques are computationally expensive. In this study, a hybrid mesh structure is proposed. Hybrid meshes are both less dependent on the geometry like unstructured meshes and computationally efficient like structured meshes
The effects of annealing on gas sensing properties of ZnO nanorod sensors coated with Pd and Pt
No full textIn this study, hydrogen (H2) gas sensing properties of palladium (Pd) & platinum (Pt) thin films coated and uncoated vertically alinged zinc oxide (ZnO) nanorods were investigated at different temperatures. On the other hand, the effects of annealing in dry air to gas sensing properties of the nanorods were investigated. Vertically aligned ZnO nanorods were fabricated by using hydrothermal method on glass substrate, and then Pd and Pt thin films was coated on to ZnO nanorods by using thermal evaporating system. The thickness of Pd or Pt thin film was approximately 15 nm. H2 sensing measurements were done in the temperature range of 25 - 200°C. It was found that the sensor response of Pd coated ZnO nanorods were much higher than uncoated ZnO nanorods because of catalytic effect Pd thin film. Moreover, unannealed samples showed better sensor response than annealed samples due to the surface charge number. The sensor response of all samples increased with enhancing temperature
Non-Hermitian Hamiltonians with a real spectrum and their physical applications
No full textWe present an evaluation of some recent attempts to understand the role of pseudo-Hermitian and PT-symmetric Hamiltonians in modelling unitary quantum systems and elaborate on a particular physical phenomenon whose discovery originated in the study of complex scattering potentials
Optical properties of native and coagulated lamb brain tissues in vitro in the visible and near-infrared spectral range
No full textThe aim of this study was to estimate optical properties (μa, μs, μl, μs, τ, α, g) of native and coagulated (al 45°C, 60°C, 80°C) lamb brain (issues in visible and near-infrared spectral range in vitro. Optical properties of cerebellum, brainstem, conical (grey matter), and sub-cortical regions (while matter) of frontal lobe (issues of lamb brain were estimated during this study. Diffused transmittance (Td). diffused reflectance (Rd), total reflectance (Rt) and total transmittance (Tl) were measured with single integrating sphere method. Data were processed with software (CAL-g3) developed in Biophotonics Laboratory in the Institute of Biomedical Engineering, Bogazici University. As a result, it was stated that both μa and μs values of (issues increased as temperature increases. Also scattering coefficients decreased with the increasing wavelength for all (issue types due to increase in Mic scattering
Bronze jugs
No full textOne of photographs of Ara Güler captured during his visits at Anatolian archaeological sites and museums.Black & white photograph