132 research outputs found

    The Magnetic Properties of 1111-type Diluted Magnetic Semiconductor (La1−x_{1-x}Bax_{x})(Zn1−x_{1-x}Mnx_{x})AsO in the Low Doping Regime

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    We investigated the magnetic properties of (La1−x_{1-x}Bax_{x})(Zn1−x_{1-x}Mnx_{x})AsO with xx varying from 0.005 to 0.05 at an external magnetic field of 1000 Oe. For doping levels of xx ≤\leq 0.01, the system remains paramagnetic down to the lowest measurable temperature of 2 K. Only when the doping level increases to xx = 0.02 does the ferromagnetic ordering appear. Our analysis indicates that antiferromagnetic exchange interactions dominate for xx ≤\leq 0.01, as shown by the negative Weiss temperature fitted from the magnetization data. The Weiss temperature becomes positive, i.e., ferromagnetic coupling starts to dominate, for xx ≥\geq 0.02. The Mn-Mn spin interaction parameter ∣\mid2J/kB2J/k_B∣\mid is estimated to be in the order of 10 K for both xx ≤\leq 0.01 (antiferromagnetic ordered state) and xx ≥\geq 0.02 (ferromagnetic ordered state). Our results unequivocally demonstrate the competition between ferromagnetic and antiferromagnetic exchange interactions in carrier-mediated ferromagnetic systems.Comment: 9 pages, 3 figure

    Individualized outcome prognostication for patients with laryngeal cancer

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142424/1/cncr31087.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142424/2/cncr31087_am.pd

    Not at Home on the Range: Peer Production and the Urban/Rural Divide

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    ABSTRACT Wikipedia articles about places, OpenStreetMap features, and other forms of peer-produced content have become critical sources of geographic knowledge for humans and intelligent technologies. In this paper, we explore the effectiveness of the peer production model across the rural/urban divide, a divide that has been shown to be an important factor in many online social systems. We find that in both Wikipedia and OpenStreetMap, peer-produced content about rural areas is of systematically lower quality, is less likely to have been produced by contributors who focus on the local area, and is more likely to have been generated by automated software agents (i.e. "bots"). We then codify the systemic challenges inherent to characterizing rural phenomena through peer production and discuss potential solutions

    Not at Home on the Range: Peer Production and the Urban/Rural Divide

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    ABSTRACT Wikipedia articles about places, OpenStreetMap features, and other forms of peer-produced content have become critical sources of geographic knowledge for humans and intelligent technologies. In this paper, we explore the effectiveness of the peer production model across the rural/urban divide, a divide that has been shown to be an important factor in many online social systems. We find that in both Wikipedia and OpenStreetMap, peer-produced content about rural areas is of systematically lower quality, is less likely to have been produced by contributors who focus on the local area, and is more likely to have been generated by automated software agents (i.e. "bots"). We then codify the systemic challenges inherent to characterizing rural phenomena through peer production and discuss potential solutions

    High-yield single-step catalytic growth of graphene nanostripes by plasma enhanced chemical vapor deposition

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    We report a single-step growth process of graphene nanostripes (GNSPs) by adding certain substituted aromatics (e.g., 1,2-dichlorobenzene) as precursors during the plasma enhanced chemical vapor deposition (PECVD). Without any active heating and by using low plasma power (≤60 W), we are able to grow GNSPs vertically with high yields up to (13 ± 4) g/m^2 in 20 min. These GNSPs exhibit high aspect ratios (from 10:1 to >∼130:1) and typical widths from tens to hundreds of nanometers on various transition-metal substrates. The morphology, electronic properties and yields of the GNSPs can be controlled by the growth parameters (e.g., the species of seeding molecules, compositions and flow rates of the gases introduced into the plasma, plasma power, and the growth time). Studies of the Raman spectra, scanning electron microscopy images, ultraviolet photoelectron spectroscopy, transmission electron microscopy images, energy-dispersive x-ray spectroscopy and electrical conductivity of these GNSPs as functions of the growth parameters confirm high-quality GNSPs with electrical mobility ∼10^4 cm^2/V-s. These results together with residual gas analyzer spectra and optical emission spectroscopy taken during PECVD growth suggest the important roles of both substituted aromatics and hydrogen plasma in the rapid vertical growth of GNSPs with large aspect ratios

    High-yield single-step catalytic growth of graphene nanostripes by plasma enhanced chemical vapor deposition

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    We report a single-step growth process of graphene nanostripes (GNSPs) by adding certain substituted aromatics (e.g., 1,2-dichlorobenzene) as precursors during the plasma enhanced chemical vapor deposition (PECVD). Without any active heating and by using low plasma power (≤60 W), we are able to grow GNSPs vertically with high yields up to (13 ± 4) g/m^2 in 20 min. These GNSPs exhibit high aspect ratios (from 10:1 to >∼130:1) and typical widths from tens to hundreds of nanometers on various transition-metal substrates. The morphology, electronic properties and yields of the GNSPs can be controlled by the growth parameters (e.g., the species of seeding molecules, compositions and flow rates of the gases introduced into the plasma, plasma power, and the growth time). Studies of the Raman spectra, scanning electron microscopy images, ultraviolet photoelectron spectroscopy, transmission electron microscopy images, energy-dispersive x-ray spectroscopy and electrical conductivity of these GNSPs as functions of the growth parameters confirm high-quality GNSPs with electrical mobility ∼10^4 cm^2/V-s. These results together with residual gas analyzer spectra and optical emission spectroscopy taken during PECVD growth suggest the important roles of both substituted aromatics and hydrogen plasma in the rapid vertical growth of GNSPs with large aspect ratios

    Navigator-assisted hypofractionation (NAVAH) to address radiation therapy access disparities facing African-Americans with breast cancer

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    Background: African-Americans have the highest overall cancer death rate and shortest survival time of any racial or ethnic group in the United States. The most common cancer studied in African-American radiation therapy (RT) access disparities research is breast cancer. The goal of this study is to evaluate the impact of patient navigation on RT access for African-American breast cancer patients. Material and methods: This study is a prospective survey-based evaluation of the impact of patient navigation on access to hypofractionated RT and financial toxicity in African-American breast cancer patients. The impact of patient navigation on RT access will be collated and analyzed from survey results pre-RT versus post-RT as well as for patients with versus without receipt of patient navigation. The validated COST-Functional Assessment of Chronic Illness Therapy score will be used to compare hypofractionation versus standard fractionated RT financial toxicity for patients with early-stage breast cancer who have received lumpectomy. Discussion: This is the first study to investigate the impact of patient navigation on reducing RT access disparities facing African-American breast cancer patients. The natural progression of this work will be to expand this model to include additional breast cancer populations most vulnerable to suffering RT access disparities (Native American, Hispanic American, Appalachian) within the United States

    Wireless transmission of biosignals for hyperbaric chamber applications

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    [EN] This paper presents a wireless system to send biosignals outside a hyperbaric chamber avoiding wires going through the chamber walls. Hyperbaric chambers are becoming more and more common due to new indications of hyperbaric oxygen treatments. Metallic walls physically isolate patients inside the chamber, where getting a patient's vital signs turns into a painstaking task. The paper proposes using a ZigBee-based network to wirelessly transmit the patient's biosignals to the outside of the chamber. In particular, a wearable battery supported device has been designed, implemented and tested. Although the implementation has been conducted to transmit the electrocardiography signal, the device can be easily adapted to consider other biosignals.The authors would like to thanks the University of Balearic Islands (UIB), the Miguel Hernandez University (UMH), MEDIBAROX unit of the Perpetuo Socorro Hospital and the "Catedra de Medicina Hiperbarica" (UMH) for their support allowing the use of its facilities for this work. The authors would also like to thank Borja Mas Boned for his help designing the LabVIEW application. This research has been carried out with funding and promotion of "Catedra de Medicina Hiperbarica" of the Miguel Hernandez University. http://nbio.umh.es/es/2010/12/01/catedra-de-medicina-hiperbarica-medibarox/.Perez-Vidal, C.; Gracia Calandin, LI.; Carmona, C.; Alorda, B.; Salinas, A. (2017). Wireless transmission of biosignals for hyperbaric chamber applications. PLoS ONE. 12(3):1-19. https://doi.org/10.1371/journal.pone.0172768S119123Sureda, A., Batle, J. M., Martorell, M., Capó, X., Tejada, S., Tur, J. A., & Pons, A. (2016). Antioxidant Response of Chronic Wounds to Hyperbaric Oxygen Therapy. PLOS ONE, 11(9), e0163371. doi:10.1371/journal.pone.0163371Branco, B. H. M., Fukuda, D. H., Andreato, L. V., Santos, J. F. da S., Esteves, J. V. D. C., & Franchini, E. (2016). The Effects of Hyperbaric Oxygen Therapy on Post-Training Recovery in Jiu-Jitsu Athletes. PLOS ONE, 11(3), e0150517. doi:10.1371/journal.pone.0150517Xu, Y., Ji, R., Wei, R., Yin, B., He, F., & Luo, B. (2016). The Efficacy of Hyperbaric Oxygen Therapy on Middle Cerebral Artery Occlusion in Animal Studies: A Meta-Analysis. PLOS ONE, 11(2), e0148324. doi:10.1371/journal.pone.0148324Lin, B.-S., Lin, B.-S., Chou, N.-K., Chong, F.-C., & Chen, S.-J. (2006). RTWPMS: A Real-Time Wireless Physiological Monitoring System. IEEE Transactions on Information Technology in Biomedicine, 10(4), 647-656. doi:10.1109/titb.2006.874194Hu, S., Wei, H., Chen, Y., & Tan, J. (2012). A Real-Time Cardiac Arrhythmia Classification System with Wearable Sensor Networks. Sensors, 12(9), 12844-12869. doi:10.3390/s120912844Burns, A., Greene, B. R., McGrath, M. J., O’Shea, T. J., Kuris, B., Ayer, S. M., … Cionca, V. (2010). SHIMMER™ – A Wireless Sensor Platform for Noninvasive Biomedical Research. IEEE Sensors Journal, 10(9), 1527-1534. doi:10.1109/jsen.2010.2045498Gil, Y., Wu, W., & Lee, J. (2012). A Synchronous Multi-Body Sensor Platform in a Wireless Body Sensor Network: Design and Implementation. Sensors, 12(8), 10381-10394. doi:10.3390/s120810381Chin-Teng Lin, Kuan-Cheng Chang, Chun-Ling Lin, Chia-Cheng Chiang, Shao-Wei Lu, Shih-Sheng Chang, … Li-Wei Ko. (2010). An Intelligent Telecardiology System Using a Wearable and Wireless ECG to Detect Atrial Fibrillation. IEEE Transactions on Information Technology in Biomedicine, 14(3), 726-733. doi:10.1109/titb.2010.2047401W. Y. Chung, Y. D. Lee, and S. J. Jung, 'A Wireless Sensor Network Compatible Wearable U-Healthcare Monitoring System Using Integrated Ecg, Accelerometer and Spo2', Conf Proc IEEE Eng Med Biol Soc, 2008 (2008), 1529–32.ZigBee Alliance; http://www.zigbee.org/Mahmood, A., Javaid, N., & Razzaq, S. (2015). A review of wireless communications for smart grid. Renewable and Sustainable Energy Reviews, 41, 248-260. doi:10.1016/j.rser.2014.08.036J.S. Lee, Y.W. Su, and C.C. Shen, "A comparative study of wireless protocols: Bluetooth, UWB, ZigBee, and Wi-Fi, 33rd Annual Conference of the IEEE Industrial Electronics Society (IECON), 2007, pp. 46–51.P.P. Parikh, M.G. Kanabar, and T.S. Sidhu, "Opportunities and challenges of wireless communication technologies for smart grid applications, IEEE PES General Meeting, 2010, pp. 1–7.Fadlullah, Z. M., Fouda, M. M., Kato, N., Takeuchi, A., Iwasaki, N., & Nozaki, Y. (2011). Toward intelligent machine-to-machine communications in smart grid. IEEE Communications Magazine, 49(4), 60-65. doi:10.1109/mcom.2011.5741147A.C. Olteanu, G.D. Oprina, N. Tapus, and S. Zeisberg, "Enabling mobile devices for home automation using ZigBee, 19th IEEE International Conference on Control Systems and Computer Science, 2013, pp. 189–195.Shang, Y. (2014). Vulnerability of networks: Fractional percolation on random graphs. Physical Review E, 89(1). doi:10.1103/physreve.89.012813R. Barea-Navarro. Biomedical Instrumentation. Chapter 3. University of Alcala
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