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HoCrO3, a member of the rare-earth chromate family, is known to exhibit an orthorhombic structure with Pbnm space group in bulk at room temperature. We have employed the pressure driven powder consolidation technique, spark plasma sintering, for synthesizing HoCrO3 powder-compact, which exhibits a superior quality with fewer defects over that synthesized by conventional solid-state sintering (resulting in a large reduction of charge carrier mediated extrinsic dielectric contribution). The powder compact shows magneto-dielectric coupling but does not exhibit a detectable ferroelectric phase in the range of 50 K to 300 K. Low temperature Raman spectra show structural distortions below 250 cm−1, indicating Ho ion displacements. Temperature evolution of the crystal structure using synchrotron x-ray diffraction reveals a probable structural phase transition below 240 K. Pyrocurrent measurement, together with synchrotron x-ray diffraction analysis, further points to a magneto-structural transition at 100 K. [ABSTRACT FROM AUTHOR]

The negative differential resistance (NDR) observed in the different current-voltage characteristics of the [Gd.sub.0.5][Sr.sub.0.5]Mn[O.sub.3] single crystals is analyzed. Joule heating is shown to be one of the main factors leading to the generation of NDR in the crystals.

Negative differential resistance (NDR) in current-voltage (I-V) characteristics and apparent colossal electroresistance were observed in Gd0.5Sr0.5MnO3 single crystals at low temperatures. The continuous dc I-V measurements showed a marked thermal drift. In addition, temperature of the sample surface was found to be significantly higher than that of the base at high applied currents. Two different strategies namely estimation and diminution of the Joule heating (pulsed I-V measurements) were employed to investigate its role in the electric transport properties. Our experiments reveal that the NDR in Gd0.5Sr0.5MnO3 is a consequence of Joule heating rather than the melting of charge order. [ABSTRACT FROM AUTHOR]

Interlayer magneto-electric coupling in BiFeO3/SrRuO3 heterostructures was investigated by impedance spectroscopy over a temperature range of 80 K-260 K. In-plane impedance measurements were performed using interdigitated gold electrodes fabricated on the BiFeO3 layer. The Nyquist plots at different temperatures were fitted with an equivalent circuit model of the heterostructure. A pronounced dip in the temperature coefficient of equivalent-capacitance and a distinct increase in the temperature coefficient of equivalent-resistance of the BiFeO3 layer were observed on cooling across ferromagnetic TC of the bottom SrRuO3 layer. Temperature dependent capacitance (at 0 T magnetic fields) and magneto-capacitance (at 5 T magnetic fields) plots showed anomalies near 160 K. A shift of the hysteresis loop along the magnetization axis in field cooled M-H measurements was also found, which indicates the presence of pinned SrRuO3 moments due to the magnetic interaction at the interface. These observations suggest a strong magneto-electric coupling between the BiFeO3 and SrRuO3 layers of this heterostructure. [ABSTRACT FROM AUTHOR]

This article first develops an integrated traffic-driving-networking simulator (ITDNS) intended for the design and evaluation of cyber transportation systems (CTS) and connected vehicle (CV) applications. The ITDNS allows a human driver to control a subject vehicle, in a virtual environment, that is capable of communicating with other vehicles and the infrastructure with CTS messages. The challenges associated with the integration of the three simulators, and how those challenges were overcome, are discussed. As an application example, an eco-signal system, which recommends the approach speed for vehicles approaching the intersection so as to minimize fuel consumption and emissions, was implemented in the ITDNS. Test drivers were then asked to virtually drive through a signalized corridor twice, one time with the eco-signal system in place and another without the system. Thanks to the human-in-the-loop component of ITDNS, the research was able to evaluate the likely benefits of the eco-signal system, while accounting for the response of human drivers to the recommended speed profiles. Moreover, the study compared the energy consumption and emission production rates of human-controlled vehicles’ approach trajectories to the rates associated with “idealistic” trajectories that may be attainable via vehicle automation. With respect to ITDNS, the study demonstrates the unique advantages of the simulator and the broad range of applications it can address. Regarding the eco-signal application example, preliminary results demonstrate the potential of the concept to result in tangible reductions of around 9% for energy consumption, 18% for carbon monoxide, and 25% for nitrogen oxides emissions. Moreover, the application eliminated hard accelerations and decelerations maneuvers, and thus may have an additional positive safety impact. [ABSTRACT FROM AUTHOR]

Vehicular Cyber-Physical Systems (VCPS) provide human drivers with various services related to road safety, and on-road infotainments. Since a service (message) delivery includes service transmission, service display and driver processing, many challenges arise due to limited network resources, possible pre-emption and contention between services for the display and non-negligible driver processing delay. In this paper, we address a new Driver-centric Service Delivery Problem (DSDP) from a cross-disciplinary resource allocation standpoint. Our goal is to deliver a number of services to a set of intended drivers in a given time period so as to maximize the system-wide performance in terms of total utility income (TUI) to drivers. We show that DSDP differs from all existing problems and is NP-Complete. A number of efficient heuristics are proposed to address several issues, including wireless transmission failure as well as distributed implementation of the multi-sender systems. Utilizing real traces collected from taxis in the city of Shanghai, we also present a case study in a more realistic scenario and conduct comprehensive simulations providing numerical results. [ABSTRACT FROM AUTHOR]

Objective: To examine practices of dentists in Texas providing dental/oral care to cancer patients., Method: Dental providers in Texas were invited via email to participate in an exploratory cross-sectional study. A non-probability voluntary convenience sampling procedure was used to recruit the sample. The online, anonymous, self-reported survey included questions to capture demographics, type of dental practice, services provided, and number of cancer patients. The study was approved by the Institutional Review Board of The university of Texas MD Anderson Cancer Center., Result: A total of 655 dentists completed the questionnaire items. Results revealed that 62% of the respondents were 51-65 years old, predominantly (68%) male, Caucasian (81%) with their dental degrees awarded in the state of Texas (77%). 91% of the dentists provide dental care to patients who are currently undergoing cancer treatment or have a history of cancer. However, 80% of the dental providers do not teach oral self-exam to their patients, which may include cancer survivors or those undergoing cancer treatment, while 32% dentists do not deliver brief interventions for effectively motivating and assisting tobacco users to quit., Conclusion: Because Texas, especially Houston, is known for world-class cancer care, dentists in the state are more likely to provide dental care to oncologic patients, especially emergency dental procedures in cancer patients facing some of the side effects of cancer treatment. Careful monitoring of oral health and reducing tobacco use are especially important during and after cancer therapy to prevent, detect, and treat complications as soon as possible. A further step in oral care for cancer patients and survivors is to train patients how to perform regular oral self-examination and to provide tobacco users with cessation counseling as part of their dental/oral treatment. These simple but comprehensive approaches, along with regular dental visits, will positively impact the health-related outcomes for cancer patients, enhancing both survival and quality of life.