Effects of mistuning on dynamic behavior of nonlinear cyclic systems with lump masses and cubic nonlinearity

Mistuning in cyclic symmetric systems increases severely the forced response of system and splits the modes. This paper concerns with nonlinear behavior of mistuned cyclic systems. A nonlinear, mistuned model based on the method of multiple scales is proposed and formulated in which nonlinearity and mistuning parameter is assumed to be in of low order. Next, two mistuned systems were considered and solved by the multiple scale technique. Numerical results demonstrate that mistuning can lead to repeating and scattering of jump phenomena during the excitation frequency whereas in tuned cyclic system it occurs simultaneously (synchronously).Peer ReviewedPostprint (published version

2-NBDG, a Fluorescent Analogue of Glucose, as a Marker for Detecting Cell Electropermeabilization In Vitro

Abstract This study investigated whether molecules spontaneously transported inside cells, like glucose derivatives, can also be used as electropermeabilization markers. Uptake of a fluorescent deoxyglucose derivative (2-NBDG) by normal and electropermeabilized cells in culture was analyzed. 2-NBDG was added to DC-3F cell suspensions and cells, exposed or not to eight square-wave electric pulses of 100-ls duration and of appropriate field amplitude at a repetition frequency of 1 Hz or 5 kHz, were incubated at 37 C. 2-NBDG uptake was temperature-, concentration- and time-dependent in cells submitted or not to the electric pulses. In spite of significant uptake of 2-NBDG mediated by GLUT transporters into nonpermeabilized cells, the electric pulses significantly increased about ten to hundred times the 2-NBDG uptake into the cells. The increase in the field amplitude from 900 to 1,500 V/cm resulted in a progressive increase of 2-NDBG. Our results show that under the conditions of in vivo exposure duration to FDG and the physiological concentration of D-glucose, electric pulses increased 2-NBDG uptake into electropermeabilized cells. Under our experimental conditions, the percentage of permeabilized cells within the population of cells exposed to electric pulses remained at the same level regardless of the pulse frequency used, 1 Hz or 5 kHz. The findings showed that glucose derivatives can also be used to detect electropermeabilized cells exposed to electric pulses

Coarse Graining Makes It Hard to See Micro-Macro Entanglement

Observing quantum effects such as superpositions and entanglement in macroscopic systems requires not only a system that is well protected against environmental decoherence, but also sufficient measurement precision. Motivated by recent experiments, we study the effects of coarse-graining in photon number measurements on the observability of micro-macro entanglement that is created by greatly amplifying one photon from an entangled pair. We compare the results obtained for a unitary quantum cloner, which generates micro-macro entanglement, and for a measure-and-prepare cloner, which produces a separable micro-macro state. We show that the distance between the probability distributions of results for the two cloners approaches zero for a fixed moderate amount of coarse-graining. Proving the presence of micro-macro entanglement therefore becomes progressively harder as the system size increases.Comment: 5 pages, 3 figure

Glucose Derivatives as Efficient Markers of Cell Reversible Electropermeabilization

Abstract— Molecules spontaneously transported inside the cells, like glucose derivatives, can also be used as electropermeabilization markers. In a previous study, we evaluated the uptake of a fluorescent deoxyglucose derivative (2-NBDG) by normal and electropermeabilized Chinese hamster cells. We extend here our previous study to two murine tumor model cells and investigate the effect of rolipram, a selective PDDE4 inhibitor, on 2-NBDG uptake by tumor cells, with or without electric pulses.2-NBDG was added to cell suspensions, and the cells exposed or not to eight square-wave electric pulses of 100- µs duration and of appropriate field amplitude delivered, were incubated at 37˚C and uptake was measured by flow cytometry. In rolipram experiments, cells were similarly processed after a 15 min pre-incubation with rolipram. In spite of significant uptake of 2-NBDG, mediated by GLUT transporters into non permeabilized cells, electric pulses significantly increased the 2-NBDG uptake into both murine tumor cells, even though the electrical parameters allowing a maximal uptake were different. Pretreatment with rolipram, only at high concentrations reduced 2-NBDG uptake in non-electropermeabilized cells, affecting more severely the DC-3F cells than the LPB cells. On the contrary, rolipram treatment did not attenuated the uptake of 2-NBDG in the electropermeabilized cells. We extended to other cell lines our previous observation that glucose derivatives can be used to detect cells reversible electropermeabilization. Moreover, our data suggest that rolipram could probably be used as a tool for improving the visualization of tumor using glucose derivatives, by affecting the uptake in the surrounding normal tissue

The Effect of Darab Salt Dome on the Quality of Adjacent Karstic and Alluvium Aquifers (South of Iran)

Zakrasele kraške formacije vsebujejo najpomembnejše vodne vire osrednjih delov jugovzhodnega Irana. Če kraška voda ni onesnažena zaradi slanih dom, je v tem delu Irana njena električna prevodnost pod 500 µS cm-1. Področje raziskav je južno krilo antiklinale Shahneshin-Milk, 200 km vzhodno od Shiraza, ki sodi v narivno cono Zagrosa. Kraška formacija Tarbur (zgornji Campanij-Maastrichtij) izdanja v južnem krilu antiklinale Shahneshin-Milk, pod katero je neprepustna radiolaritna formacija. Solna doma Darab izdanja znotraj zakrasele formacije Tarbur. Iz formacije Tarbur priteka več izvirov. Kvaliteta vode vseh izvirov je v mejah neonesnažene kraške vode razen treh, ki so v bližini solne dome. Električna prevodnost teh treh izvirov je med 1200 in 2000 µS cm-1. Del aluvija okoli solne dome je slano močvirje, ki ga obrobljata dva kanala. Električna prevodnost močvirske vode pod nivojem talne vode je okoli 1400 µS cm-1, v večjih globinah pa se zmanjša na 400 µS cm-1. Odtok s solne dome Darab in prenikanje vode nizke kakovosti iz kanala sta najbrž glavna vzroka za nastanek slanega močvirja. Pomemben delež onesnažene kraške vode iz Tarburja ne teče proti močvirju, saj, prvič, večina kraške vode iz Tarburja priteka na dan skozi izvire, in drugič, na globlje plasti aluvijalnega vodonosnika onesnažena voda ne vpliva.Karstified carbonate formations are among the most important water resources in the south-central regions of Iran. If the karst water is not contaminated by salt domes, the electrical conductivity of water in the karst aquifer is less than 500 µS cm-1 in the south-center of Iran. The study area is located in the southern flank of Shahneshin-Milk anticline, 200 km east of Shiraz. This region is situated in the Zagros Thrust Zone. The Tarbur karstic formation (Late Campanian-Maastrichtian) is outcropped on the southern flank of the Shahneshin-Milk anticline which is underlain by the impermeable Radiolarite formation. The Darab salt dome outcrops inside the karstified Tarbur Formation. Several springs emerge from the Tarbur Formation. The quality of all springs is in the range of unpolluted karst water except for three springs which are located near the Darab salt dome. The electrical conductivity of these springs range from 1200 to 2000 µS cm-1. Part of the alluvium near the Darab salt dome is salt-marsh which is bounded by two channels. The electrical conductivity in the salt-marsh below the water table is about 1400 µS cm-1, and it reduces to 400 µS cm-1 at the lower depths. Run-off from the Darab salt dome and seepage from the channel with low quality water are probably the main reasons of salt-marsh development. A considerable amount of polluted Tarbur karst water does not flow towards the marshland because, firstly, most of the Tarbur karst water discharges from the springs, and secondly, the alluvium aquifer is not affected by polluted water at lower depths

A new approach for quantitative evaluation of reconstruction algorithms in SPECT

Background: In nuclear medicine, phantoms are mainly used to evaluate the overall performance of the imaging systems, and practically there is no phantom exclusively designed for the evaluation of the software performance. In this study the Hoffman brain phantom was used for quantitative evaluation of reconstruction techniques. The phantom is modified to acquire tomographic and planar image of the same structure. The planar image may be used as the reference image to evaluate the quality of reconstructed slices, using the companion software developed in MATLAB. Materials and Methods: The designed phantom was composed of 4 independent 2D slices that could have been placed juxtapose to the 3D phantom. Each slice was composed of objects of different size and shape (for example: circle, triangle, and rectangle). Each 2D slice was imaged at distances ranging from 0 to 15 cm from the collimator surface. The phantom in 3D configuration was imaged acquiring 128 views of 128×128 matrix size. Reconstruction was performed using different filtering condition and the reconstructed images were compared to the corresponding planar images. The modulation transfer function, scatter fraction and attenuation map were calculated for each reconstructed image. Results: Since all the parameters of the acquisition were identical for the 2D and the 3D imaging, it was assumed that the difference in the quality of the images has exclusively been due to the reconstruction condition. The planar images were assumed to be the most perfect images which could be obtained with the system. The comparison of the reconstructed slices with the corresponding planar images yielded the optimum reconstruction condition. The results clearly showed that Wiener filter yields superior quality image among the entire tested filters. The extent of the improvement has been quantified in terms of universal image quality index. Conclusion: The phantom and the accompanying software were evaluated and found to be quite useful in determining the optimum filtering condition and mathematical evaluation of the scatter and attenuation in tomographic images. A new approach for quantitative evaluation of reconstruction algorithms in SPECT (PDF Download Available). Available from: https://www.researchgate.net/publication/229005593_A_new_approach_for_quantitative_evaluation_of_reconstruction_algorithms_in_SPECT [accessed Nov 07 2017]

Evaluation of the radiosensitizing potency of bromelain for radiation therapy of 4T1 breast cancer cells

Breast cancer (BC) remains the leading cause of death in women worldwide, despite the improvements of cancer screening and treatment methods. Recently, development of novel anticancer drugs for the improved prevention and treatment of BC is in the center of research. The anticancer effects of bromelain, as enzyme extract derived from the pineapples, contains chemicals that interfere with the growth of tumor cells. The aim of this study was to evaluate the effect of radiosensitizing of bromelain in 4T1 BC cells. This investigation utilized the 3-(4,5-dimethylthiazol-2-yl)-2,5-dimethyltetrazolium bromide assay to characterize the cytotoxicity of bromelain. Colony formation method was used to establish the truth of the capability of bromelain to make sensitive to radiation therapy. Flowcytometry performed to define the contribution the apoptosis effect to bromelain mediated radiosensitization of 4T1 cells. Bromelain reduced growth and proliferation of 4T1 cell as a concentration-dependence manner significantly. The survival of 4T1 cancer cells was decreased after combined treatment in a number and size-dependent manner with regard to the control group (P < 0.05). Combination of bromelain with radiation does not influence 4T1 cell apoptosis. The results suggested that bromelain can inhibit the growth and proliferation and reduce survival of 4T1 BC cells and might be used as a candidate radiosensitizer in BC patien

Performance evaluation of FBP reconstruction in SPECT Imaging

Abstract Introduction: The purpose of this study was to define an optimal parameter for the tomographic reconstruction procedure in routine single photon emission tomography (SPECT) studies. In this study Hoffman Brain Phantom is modified in such a way that only software capability is evaluated. The phantom is composed of several independent slice that can be imaged individually (planar) or in 3-D composition (SPECT). Method and Materials: Planar image of the slices were imaged separately. The tomographic image was ..

The effect of high-frequency electric pulses on tumor blood flow in vivo

Abstract The aim of this study was to evaluate the effect of a 5-kHz repetition frequency of electroporating electric pulses in comparison to the standard 1-Hz frequency on blood flow of invasive ductal carcinoma tumors in Balb/C mice. Electroporation was performed by the delivery of eight electric pulses of 1,000 V cm-1 and 100 ls duration at a repetition frequency of 1 Hz or 5 kHz. Blood flow changes in tumors were measured by laser Doppler flowmetry. Monitoring was performed continuously for 10 min before application of the electric pulses as well as immediately after application of the electric pulses for 40 min. The delivery of electric pulses to tumors induced changes in tumor blood flow. The reduction in blood flow started after the stimulation and continued for the 40-min period of observation. There was a significant difference in blood flow changes 3 min after application of the electric pulses at 1-Hz or 5-kHz repetition frequency. However, after 3 min the difference became nonsignificant. The findings showed that the high pulse frequency (5 kHz) had an effect comparable to the 1-Hz frequency on tumor blood flow except at very short times after pulse delivery, when pulses at 5 kHz produced a more intense reduction of blood flo

Asymptomatic bacteriuria and pyuria in patients with chronic renal failure undergoing hemodialysis at dialysis centers in Kermanshah, Iran

Pyuria is the presence of increased numbers of polymorphonuclear leukocytes in the urine and is evidence of an inflammatory response in the Urinary Tract Infection (UTI). The aim of this study is determination asymptomatic bacteriuria and pyuria in patients undergoing hemodialysis with chronic renal failure. Out of 103 patients with renal failure undergoing hemodialysis who were able to produce urine with clean catch way, we received urine sample. All samples were examined by the Microbiologist in Central Laboratory of Kermanshah, Iran. The mean age for the patients at diagnosis was 42.4 years (range, 20-67 years). Sixty-four patients (62.5) were male and thirty-nine (37.5) were female. Results have been showed 39 cases were aged between 44-49 years and the highest number cases were middle-aged. Out of 31 patients with leukocytosis, 14 patients had age between 44-49 years and majority of them were male. Pyuria(>10 WBC/HPF or 10 WBC/HPF) developed colony count more than 105 colony-forming units per milliliter that indicating positive culture. Microorganisms didn�t grow in patients (10/19) with pyuria (10 WBC/HPF is a good marker for significant bacteriuria in these patients. © 2015 Academic Journals Inc