319 research outputs found

    Spatial landslide susceptibility mapping using integrating an adaptive neuro-fuzzy inference system (ANFIS) with two multi-criteria decision-making approaches

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    Landslide is a type of slope process causing a plethora of economic damage and loss of lives worldwide every year. This study aimed to analyze spatial landslide susceptibility mapping in the Khalkhal-Tarom Basin by integrating an adaptive neuro-fuzzy inference system (ANFIS) with two multi-criteria decision-making approaches, i.e., the best-worst method (BWM) and the stepwise weight assessment ratio analysis (SWARA) techniques. For this purpose, the first step was to prepare a landslide inventory map, which was then divided randomly into the ratio of 70/30% for model training and validation. Thirteen conditioning factors were selected based on the previous studies and available data. In the next step, the BWM and the SWARA methods were utilized to determine the relationships between the sub-criteria and landslides. Finally, landslide susceptibility maps were generated by implementing ANFIS-BWM and ANFIS-SWARA ensemble models, and then several quantitative indices such as positive predictive value, negative predictive value, sensitivity, specificity, accuracy, root-mean-square-error, and the ROC curve were employed to appraise the predictive accuracy of each model. The results indicated that the ANFIS-BWM ensemble model (AUC = 75%, RMSE = 0.443) has better performance than ANFIS-SWARA (AUC = 73.6%, RMSE = 0.477). At the same time, the ANFIS-BWM model had the maximum sensitivity, specificity, and accuracy with values of 87.1%, 54.3%, and 40.7%, respectively. As a result, the BWM method was more efficient in training the ANFIS. Evidently, the generated landslide susceptibility maps (LSMs) can be very efficient in managing land use and preventing the damage caused by the landslide phenomenon. Graphical abstract: [Figure not available: see fulltext.

    Offshore wind farm layouts designer software's

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    Offshore wind energy can be considered one of the renewable energy sources with high force potential installed in marine areas. Consequently, the best wind farm layouts identified for constructing combined offshore renewable energy farms are crucial. To this aim, offshore wind potential analysis is essential to highlight the best offshore wind layouts for farm installation and development. Furthermore, the offshore wind farm layouts must be designed and developed based on the offshore wind accurate assessment to identify previously untapped marine regions. In this case, the wind speed distribution and correlation, wind direction, gust speed and gust direction for three sites have been analyzed, and then two offshore wind farm layout scenarios have been designed and analyzed based on two offshore wind turbine types in the Northwest Persian Gulf. In this case, offshore wind farm layouts software and tools have been reviewed as ubiquitous software tools. The results show Beacon M28 and Sea Island buoys location that the highest correlation between wind and gust speeds is between 87% and 98% in Beacon M28 and Sea Island Buoy, respectively. Considerably, the correlation between wind direction and wind speed is negligible. The Maximum likelihood algorithm, the WAsP algorithm, and the Least Squares algorithm have been used to analyze the wind energy potential in offshore buoy locations of the Northwest Persian Gulf. In addition, the wind energy generation potential has been evaluated in different case studies. For example, the Umm Al-Maradim buoy area has excellent potential for offshore wind energy generation based on the Maximum likelihood algorithm, WAsP algorithm, and Least Squares algorithm

    A primary offshore wind farm site assessment using reanalysis data: a case study for Samothraki island

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    The correct strategy for monitoring and assessing marine Renewable Energy Sources (RESs) is of great importance for local/national sustainable development. To achieve this goal, it is necessary to measure in the most precise possible manner the local/regional RESs potential. This is especially true for Offshore Wind (OW) energy potential, since the most precise techniques are long and expensive, and are not able to assess the RESs potential of large areas. Today, Remote Sensing (RS) satellites can be considered the most important land and marine observation tools. The RS tools can be used to identify the interested areas for future OW energy converters installations in large and small-scale areas. In this study, the OW energy potential has been analysed by means of a 40 years wind speed data from the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis dataset of the Samothraki island surrounding area in the Mediterranean Sea. The OW speed potential has been analysed by means of monthly data from ECMWF Interim reanalysis (ERA-Interim) datasets using the Network Common Data Form (NetCDF) format. Automatically, analyses have been carried out using the Region Of Interest (ROI) tool and Geographical Information System (GIS) software in order to extract information about the OW speed assessment of the Samothraki island area. The primary results of this study show that the southwest area of Samothraki island has good potential for future OW farms installation (bottom fixed and floating version) in near and offshore areas. This study shows the OW energy potential per location, as well as the trend of OW speed, which has changed over the past 40 years in the Mediterranean Sea

    Environmental Risk Assessment of Selected Antibiotics in Iran

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    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

    Single trace terahertz spectroscopic ellipsometry

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    © 2019 Optical Society of America. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibited"[EN] A new technique for terahertz time-domain ellipsometry is presented. Information of reflection coefficients of the sample in two orthogonal polarizations is encoded on the same terahertz trace by using a birefringent medium. This allows for single measurement refractive index extraction without the need for a moving analyzer. A comparison of the complex refractive index measurements of optical grade fused silica and non birefringent sapphire are carried out both in reflection ellipsometry and with a standard terahertz transmission spectrometer showing good agreement. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing AgreementMinisterio de Ciencia, Innovación y Universidades (TEC2016-80906-R).Báez-Chorro, MÁ.; Vidal Rodriguez, B. (2019). Single trace terahertz spectroscopic ellipsometry. Optics Express. 27(24):35468-35474. https://doi.org/10.1364/OE.27.035468S35468354742724Bockelt, A., Palaci Lopez, J., & Vidal, B. (2015). All-Fiber Centralized Architecture for Parallel Terahertz Sensors. IEEE Transactions on Terahertz Science and Technology, 5(1), 137-144. doi:10.1109/tthz.2014.2373313Khazan, M., Meissner, R., & Wilke, I. (2001). Convertible transmission-reflection time-domain terahertz spectrometer. Review of Scientific Instruments, 72(8), 3427-3430. doi:10.1063/1.1384433Liu, H.-B., Chen, Y., Bastiaans, G. J., & Zhang, X.-C. (2006). Detection and identification of explosive RDX by THz diffuse reflection spectroscopy. Optics Express, 14(1), 415. doi:10.1364/opex.14.000415Sanjuan, F., Bockelt, A., & Vidal, B. (2014). Birefringence measurement in the terahertz range based on double Fourier analysis. Optics Letters, 39(4), 809. doi:10.1364/ol.39.000809Nagashima, T., & Hangyo, M. (2001). Measurement of complex optical constants of a highly doped Si wafer using terahertz ellipsometry. Applied Physics Letters, 79(24), 3917-3919. doi:10.1063/1.1426258Matsumoto, N., Hosokura, T., Nagashima, T., & Hangyo, M. (2011). Measurement of the dielectric constant of thin films by terahertz time-domain spectroscopic ellipsometry. Optics Letters, 36(2), 265. doi:10.1364/ol.36.000265Galuza, A. A., Kiseliov, V. K., Kolenov, I. V., Belyaeva, A. I., & Kuleshov, Y. M. (2016). Developments in THz-Range Ellipsometry: Quasi-Optical Ellipsometer. IEEE Transactions on Terahertz Science and Technology, 6(2), 183-190. doi:10.1109/tthz.2016.2525732Morris, C. M., Aguilar, R. V., Stier, A. V., & Armitage, N. P. (2012). Polarization modulation time-domain terahertz polarimetry. Optics Express, 20(11), 12303. doi:10.1364/oe.20.012303Iwata, T., Uemura, H., Mizutani, Y., & Yasui, T. (2014). Double-modulation reflection-type terahertz ellipsometer for measuring the thickness of a thin paint coating. Optics Express, 22(17), 20595. doi:10.1364/oe.22.020595Byrne, M. B., Shaukat, M. U., Cunningham, J. E., Linfield, E. H., & Davies, A. G. (2011). Simultaneous measurement of orthogonal components of polarization in a free-space propagating terahertz signal using electro-optic detection. Applied Physics Letters, 98(15), 151104. doi:10.1063/1.3579258Guo, Q., Zhang, Y., Lyu, Z., Zhang, D., Huang, Y., Meng, C., … Yuan, J. (2019). THz Time-Domain Spectroscopic Ellipsometry With Simultaneous Measurements of Orthogonal Polarizations. IEEE Transactions on Terahertz Science and Technology, 9(4), 422-429. doi:10.1109/tthz.2019.2921200Pupeza, I., Wilk, R., & Koch, M. (2007). Highly accurate optical material parameter determination with THz time-domain spectroscopy. Optics Express, 15(7), 4335. doi:10.1364/oe.15.004335Grischkowsky, D., Keiding, S., van Exter, M., & Fattinger, C. (1990). Far-infrared time-domain spectroscopy with terahertz beams of dielectrics and semiconductors. Journal of the Optical Society of America B, 7(10), 2006. doi:10.1364/josab.7.002006Kim, Y., Yi, M., Kim, B. G., & Ahn, J. (2011). Investigation of THz birefringence measurement and calculation in Al_2O_3 and LiNbO_3. Applied Optics, 50(18), 2906. doi:10.1364/ao.50.002906Chen, X., Parrott, E. P. J., Huang, Z., Chan, H.-P., & Pickwell-MacPherson, E. (2018). Robust and accurate terahertz time-domain spectroscopic ellipsometry. Photonics Research, 6(8), 768. doi:10.1364/prj.6.000768Neshat, M., & Armitage, N. P. (2012). Terahertz time-domain spectroscopic ellipsometry: instrumentation and calibration. Optics Express, 20(27), 29063. doi:10.1364/oe.20.029063Van Exter, M., Fattinger, C., & Grischkowsky, D. (1989). Terahertz time-domain spectroscopy of water vapor. Optics Letters, 14(20), 1128. doi:10.1364/ol.14.00112

    Combinatorial CRISPR-Cas9 screens for de novo mapping of genetic interactions.

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    We developed a systematic approach to map human genetic networks by combinatorial CRISPR-Cas9 perturbations coupled to robust analysis of growth kinetics. We targeted all pairs of 73 cancer genes with dual guide RNAs in three cell lines, comprising 141,912 tests of interaction. Numerous therapeutically relevant interactions were identified, and these patterns replicated with combinatorial drugs at 75% precision. From these results, we anticipate that cellular context will be critical to synthetic-lethal therapies

    Dual EGFR and mTOR targeting in squamous cell carcinoma models, and development of early markers of efficacy

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    The epidermal growth factor receptor (EGFR) is a validated target in squamous cell carcinoma (SCC) of the head and neck. Most patients, however, do not respond or develop resistance to this agent. Mammalian target of rapamycin (mTOR) is involved in the pathogenesis of SCC of the head and neck (SCCHN). This study aimed to determine if targeting mTOR in combination with EGFR is effective in SCC, and to develop early pharmacodynamic markers of efficacy. Two SCC cell lines, one resistant (HEP2) and one of intermediate susceptibility (Detroit 562) to EGFR inhibitors, were xenografted in vivo and treated with an mTOR inhibitor (temsirolimus), an EGFR inhibitor (erlotinib) or a combination of both. Temsirolimus exerted superior growth arrest in both cell lines than erlotinib. The combined treatment resulted in synergistic antitumor effects in the Detroit 562 cell line. Immunohistochemical assessment of pharmacodynamic effects in fine-needle aspiration (FNA) biopsies early after treatment using phospho MAPK, Phospho-P70 and Ki67 as end points demonstrated pathway abrogation in the Detroit 562 tumours treated with the combination, the only group where regressions were seen. In conclusion, an mTOR inhibitor showed antitumor activity in EGFR-resistant SCC cell lines. Marked antitumor effects were associated with dual pathway inhibition, which were detected by early FNA biopsies

    Activation of PI3K/mTOR pathway occurs in most adult low-grade gliomas and predicts patient survival

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    Recent evidence suggests the Akt-mTOR pathway may play a role in development of low-grade gliomas (LGG). We sought to evaluate whether activation of this pathway correlates with survival in LGG by examining expression patterns of proteins within this pathway. Forty-five LGG tumor specimens from newly diagnosed patients were analyzed for methylation of the putative 5′-promoter region of PTEN using methylation-specific PCR as well as phosphorylation of S6 and PRAS40 and expression of PTEN protein using immunohistochemistry. Relationships between molecular markers and overall survival (OS) were assessed using Kaplan-Meier methods and exact log-rank test. Correlation between molecular markers was determined using the Mann-Whitney U and Spearman Rank Correlation tests. Eight of the 26 patients with methylated PTEN died, as compared to 1 of 19 without methylation. There was a trend towards statistical significance, with PTEN methylated patients having decreased survival (P = 0.128). Eight of 29 patients that expressed phospho-S6 died, whereas all 9 patients lacking p-S6 expression were alive at last follow-up. There was an inverse relationship between expression of phospho-S6 and survival (P = 0.029). There was a trend towards decreased survival in patients expressing phospho-PRAS40 (P = 0.077). Analyses of relationships between molecular markers demonstrated a statistically significant positive correlation between expression of p-S6(235) and p-PRAS40 (P = 0.04); expression of p-S6(240) correlated positively with PTEN methylation (P = 0.04) and negatively with PTEN expression (P = 0.03). Survival of LGG patients correlates with phosphorylation of S6 protein. This relationship supports the use of selective mTOR inhibitors in the treatment of low grade glioma

    On a smoothed penalty-based algorithm for global optimization

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    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
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