60 research outputs found

    Quantum Sensing with Scanning Near-Field Optical Photons Scattered by an Atomic-Force Microscope Tip

    Full text link
    Scattering scanning near-field optical microscopy (s-SNOM) is known as a promising technique for overcoming Abbe diffraction limit and substantially enhancing the spatial resolution in spectroscopic imaging. The s-SNOM works by exposing an atomic force microscope (AFM) tip to an optical electromagnetic (EM) field, while the tip is so close to a sample that the incident beam lies within the near-field regime and displays nonlinear behaviour. We suggest replacing the incident field by quantized EM fields, i.e. photons, and propose a quantum model for the suggested system, by employing electric-dipole approximation, image theory, and perturbation theory. Quantum state of scattered photons from the AFM tip is extracted from the proposed model, which contain information about electrical permittivity of the dielectric material beneath the tip. The permittivity of the sample can be extracted through spectroscopic setups. Our proposed scheme can be used for quantum imaging or quantum spectroscopy with high resolution.Comment: 4 pages and 3 figure

    Environmental Risk Assessment of Selected Antibiotics in Iran

    Get PDF
    In recent years the increasing use of pharmaceuticals and personal-care products (PPCPs), especially antibiotics, has become a particular concern because of their undesirable potential ecological and human health effects. This study presents an environmental risk assessment for the aquatic environment of some frequently used antibiotics in Iran in three stages including; a short literature review about antibiotic consumption in Iran, a comprehensive estimation regarding acute toxicity of selected antibiotics and finally calculation of Risk Quotient (RQ) using the predicted environmental concentration (PEC) and the predicted no-effect concentration (PNEC). According to recently published data, the consumption of antibiotics in Iran is several times greater than European countries and in case of antibiotics (e.g. Penicillin) is approximately 10 times greater than Scandinavian region. The calculated PECs were ranged from 0.0071 to 0.8570 and the PNECs value based on ecotoxicity data was found for all studied antibiotics (varied from 0.0037 to 177). The RQ exceeded one for Amoxicillin, Penicillin G, Sulfamethoxazole, and Erythromycin. Amoxicillin has the highest risk to aquatic organisms based on this study. With respect to the emergence of microbial resistance, it is important to begin monitoring the most frequently used antibiotic

    Seroepidemiology of Toxocara canis in Children under 14 Years Referring to Laboratories of Sistan and Baluchestan Province in Southeast of Iran

    Get PDF
    Background: The aim of the present survey was to assess thr seroepidemiologic and parasitological aspects of Toxocara canis infection in children under 14 yr old. Methods: Overall, 963 sera were collected from children in the Sistan and Baluchistan Province, Southeast of Iran during the period from Sep 2015 to Jun 2016. IgG antibody against T. canis in the subjects’ sera was evaluated using the commercial ELISA kit. Results: Anti-Toxocara IgG were detected in the serum of 17 (1.7%) of the participants. In the examined children, the highest presence of anti-Toxocara antibodies was 2.1% (9/418) in 6-10-yr olds, which was higher than other age groups (P<0.05). Anti-Toxocara antibodies were significantly higher in males (2.4% or 12/492) than in females (1.1% or 5/471) (P<0.03). Highest serological prevalence of T. canis occurred in tribes (5.5% or 4/69), followed by rural areas (0.9% or 7/757), while in the urban area it was 0.1% (6/163) (P<0.01). A significant association was seen between the serological prevalence of T. canis and laboratory findings such as eosinophilia (P=0.001) and red blood cell count (P=0.02). Conclusion: Seroprevalence of Toxocara infection is high among children living in the poor regions of southeast Iran

    On a smoothed penalty-based algorithm for global optimization

    Get PDF
    This paper presents a coercive smoothed penalty framework for nonsmooth and nonconvex constrained global optimization problems. The properties of the smoothed penalty function are derived. Convergence to an ε -global minimizer is proved. At each iteration k, the framework requires the ε(k) -global minimizer of a subproblem, where ε(k)→ε . We show that the subproblem may be solved by well-known stochastic metaheuristics, as well as by the artificial fish swarm (AFS) algorithm. In the limit, the AFS algorithm convergence to an ε(k) -global minimum of the real-valued smoothed penalty function is guaranteed with probability one, using the limiting behavior of Markov chains. In this context, we show that the transition probability of the Markov chain produced by the AFS algorithm, when generating a population where the best fitness is in the ε(k)-neighborhood of the global minimum, is one when this property holds in the current population, and is strictly bounded from zero when the property does not hold. Preliminary numerical experiments show that the presented penalty algorithm based on the coercive smoothed penalty gives very competitive results when compared with other penalty-based methods.The authors would like to thank two anonymous referees for their valuable comments and suggestions to improve the paper. This work has been supported by COMPETE: POCI-01-0145-FEDER-007043 and FCT - Fundac¸ao para a Ci ˜ encia e Tecnologia within the projects UID/CEC/00319/2013 and ˆ UID/MAT/00013/2013.info:eu-repo/semantics/publishedVersio

    Loss of PTEN function may account for reduced proliferation pathway sensitivity to LY294002 in human prostate and bladder cancer cells.

    Get PDF
    PURPOSE: Inhibition of phosphoinositide 3 (PI3)-kinase pathway is attractive for cancer treatment. To examine the role of the phosphatase and tensin homolog (PTEN) in the development of resistance to the treatment. METHODS: We cultured human prostate cancer cells (DU145 and PC-3 cells) and bladder cancer cells (EJ-1 and UM-UC-3 cells) with a PI3-kinase inhibitor, LY294002 for more than 6 weeks and cell proliferation was studied. Activation of Akt1 and ERK was examined by immunoblotting. We introduced the wild type PTEN in UM-UC-3 cells and their proliferation along with the signaling pathways was also examined. RESULTS: After 6 weeks, proliferation pathway sensitivity to LY294002 was reduced in cells expressing PTEN, but not in PTEN-null cells. PD98059, a MAPK/ERK kinase inhibitor, significantly inhibited proliferation of PTEN-expressing cells, but not PTEN-null cells. Stable PTEN expression in PTEN-null UM-UC-3 cells increased serum-induced ERK activation and sensitivity to PD98059-treatment, and reduced sensitivity to LY294002 after 6 weeks of exposure. CONCLUSIONS: Loss of PTEN function may protect against resistance to PI3-kinase inhibitors through an addiction to the PI3-kinase/Akt pathway

    Proceedings of the 29th EG-ICE International Workshop on Intelligent Computing in Engineering

    Get PDF
    This publication is the Proceedings of the 29th EG-ICE International Workshop on Intelligent Computing in Engineering from July 6-8, 2022. The EG-ICE International Workshop on Intelligent Computing in Engineering brings together international experts working on the interface between advanced computing and modern engineering challenges. Many engineering tasks require open-world resolution of challenges such as supporting multi-actor collaboration, coping with approximate models, providing effective engineer-computer interaction, search in multi-dimensional solution spaces, accommodating uncertainty, including specialist domain knowledge, performing sensor-data interpretation and dealing with incomplete knowledge. While results from computer science provide much initial support for resolution, adaptation is unavoidable and most importantly, feedback from addressing engineering challenges drives fundamental computer-science research. Competence and knowledge transfer goes both ways. &nbsp
    • …
    corecore