Numerical analysis of a hypersonic turbulent and laminar flow using a commercial cfd solver

Computational fluid dynamics computations for two hypersonic flow cases using the commercial ANSYS FLUENT 16.2 CFD software were done. In this paper, an internal and external hypersonic flow cases were considered and analysis of the hypersonic flow using different turbulence viscosity models available in ANSYS FLUENT 16.2 as well as the laminar viscosity model were done. The obtained results were after compared and commented upon

Quantum clocks are more accurate than classical ones

A clock is, from an information-theoretic perspective, a system that emits information about time. One may therefore ask whether the theory of information imposes any constraints on the maximum precision of clocks. Here we show a quantum-over-classical advantage for clocks or, more precisely, the task of generating information about what time it is. The argument is based on information-theoretic considerations: we analyse how the accuracy of a clock scales with its size, measured in terms of the number of bits that could be stored in it. We find that a quantum clock can achieve a quadratically improved accuracy compared to a purely classical one of the same size.Comment: 17 + 60 pages. V2: corrected typos and improved discussio

Homicidal parathion poisoning

Opisana su dva slučaja ubilačkog trovanja parationom na selu. Autor ističe potrebu stroge kontrole distribucije otrovnih insekticida i neophodnost obdukcije svakog slučaja izvan grada koji pre smrti nije tretiran od strane lekara.Two cases of homicidal Parathion poisoning in a village are described. The necessity of a strict control over the distribution of poisonous insecticides and of the autopsy of each case occurring in the country and not treated by the doctor is strongly emphasized

Simple and Low-cost Fiber-optic Sensors for Detection of UV Radiation

In this paper two simple and low-cost fiberoptic sensors for detection of UV radiation are presented. A U-shaped sensor covered with an UV marker for UV radiation detection and a fiber-optic sensor with one end covered with powder from a mercury lamp are produced and described in details. Both sensors are made of large-core PMMA plastic optical fibers. As UV sources, a solar simulator and four different UV lamps are used. The light spectrum on the fiber output is measured by using an USB spectrometer. Dependence of output light intensity on the distance of end-type sensor with powder from a mercury lamp from UV lamp is investigated as well. On the output of the sensor covered with powder from a mercury lamp are obtained peaks of fluorescent emission at approximately 616 nm and 620 nm wavelengths

Multi-frequency study of a new Fe-rich supernova remnant in the Large Magellanic Cloud, MCSNR J0508-6902

We present a detailed radio, X-ray and optical study of a newly discovered Large Magellanic Cloud (LMC) supernova remnant (SNR) which we denote MCSNR J0508-6902. Observations from the Australian Telescope Compact Array (ATCA) and the $\textit{XMM-Newton}$ X-ray observatory are complemented by deep H$\alpha$ images and Anglo Australian Telescope AAOmega spectroscopic data to study the SNR shell and its shock-ionisation. Archival data at other wavelengths are also examined. The remnant follows a filled-in shell type morphology in the radio-continuum and has a size of $\sim$74 pc $\times$ 57 pc at the LMC distance. The X-ray emission exhibits a faint soft shell morphology with Fe-rich gas in its interior $-$ indicative of a Type Ia origin. The remnant appears to be mostly dissipated at higher radio-continuum frequencies leaving only the south-eastern limb fully detectable while in the optical it is the western side of the SNR shell that is clearly detected. The best-fit temperature to the shell X-ray emission ($kT = 0.41^{+0.05}_{-0.06}$ keV) is consistent with other large LMC SNRs. We determined an O/Fe ratio of $<21$ and an Fe mass of 0.5-1.8$~M_{\odot}$ in the interior of the remnant, both of which are consistent with the Type Ia scenario. We find an equipartition magnetic field for the remnant of $\sim$28 $\mu$G, a value typical of older SNRs and consistent with other analyses which also infer an older remnant

Nano-Motion Analysis for Rapid and Label Free Assessing of Cancer Cell Sensitivity to Chemotherapeutics.

Background and Objectives: Optimization of chemotherapy is crucial for cancer patients. Timely and costly efficient treatments are emerging due to the increasing incidence of cancer worldwide. Here, we present a methodology of nano-motion analysis that could be developed to serve as a screening tool able to determine the best chemotherapy option for a particular patient within hours. Materials and Methods: Three different human cancer cell lines and their multidrug resistant (MDR) counterparts were analyzed with an atomic force microscope (AFM) using tipless cantilevers to adhere the cells and monitor their nano-motions. Results: The cells exposed to doxorubicin (DOX) differentially responded due to their sensitivity to this chemotherapeutic. The death of sensitive cells corresponding to the drop in signal variance occurred in less than 2 h after DOX application, while MDR cells continued to move, even showing an increase in signal variance. Conclusions: Nano-motion sensing can be developed as a screening tool that will allow simple, inexpensive and quick testing of different chemotherapeutics for each cancer patient. Further investigations on patient-derived tumor cells should confirm the method's applicability

Measurement of 60CO gamma radiation induced attenuation in multimode step-index POF at 530 nm

As optical fibres are used ever more extensively in space applications, nuclear industry, medicine and high-energy physics experiments, it has become essential to investigate the influence of ionizing radiation on their characteristics. In this work, the radiation-induced attenuation at 530 nm is investigated experimentally in step-index multimode polymethyl-methacrylate plastic optical fibres exposed to low dose-rate gamma radiation. Cumulative doses ranged from 50 Gy to 500 Gy. The radiation induced attenuation has been empirically found to obey the power law RIA= aDb, where D is the total radiation dose and a and b are the constants determined by fitting

Fracture mechanics analysis of damaged turbine rotor discs using finite element method

This paper presents evaluation fracture mechanics parameters in low pressure turbine components. Critical locations such as keyway and dovetail area are experiencing stress concentration leading to crack initiation. Stress intensity factors were evaluated using the J-Integral approach available within ANSYS software code. The finite element method allowed the prediction of the point of crack initiation and the crack propagation using the orientations of the maximum principal stresses. Special attention in this investigation is focused to develop analytic expressions for stress intensity factors at critical location of low pres-sure steam turbine disc. [Projekat Ministarstva nauke Republike Srbije, br. I-174001 i br. TR-35045

Development and pilot evaluation of a personalized decision support intervention for low risk prostate cancer patients.

ObjectivesDevelopment and pilot evaluation of a personalized decision support intervention to help men with early-stage prostate cancer choose among active surveillance, surgery, and radiation.MethodsWe developed a decision aid featuring long-term survival and side effects data, based on focus group input and stakeholder endorsement. We trained premedical students to administer the intervention to newly diagnosed men with low-risk prostate cancer seen at the University of California, San Francisco. Before the intervention, and after the consultation with a urologist, we administered the Decision Quality Instrument for Prostate Cancer (DQI-PC). We hypothesized increases in two knowledge items from the DQI-PC: How many men diagnosed with early-stage prostate cancer will eventually die of prostate cancer? How much would waiting 3&nbsp;months to make a treatment decision affect chances of survival? Correct answers were: "Most will die of something else" and "A little or not at all."ResultsThe development phase involved 6 patients, 1 family member, 2 physicians, and 5 other health care providers. In our pilot test, 57 men consented, and 44 received the decision support intervention and completed knowledge surveys at both timepoints. Regarding the two knowledge items of interest, before the intervention, 35/56 (63%) answered both correctly, compared to 36/44 (82%) after the medical consultation (P&nbsp;=&nbsp;.04 by chi-square test).ConclusionsThe intervention was associated with increased patient knowledge. Data from this pilot have guided the development of a larger scale randomized clinical trial to improve decision quality in men with prostate cancer being treated in community settings