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The Laurentian Great Lakes, one of the world's largest surface freshwater systems, pose a modeling challenge in seasonal forecast and climate projection. While physics-based hydrodynamic modeling is a fundamental approach, improving the forecast accuracy remains critical. In recent years, machine learning (ML) has quickly emerged in geoscience applications, but its application to the Great Lakes hydrodynamic prediction is still in its early stages. This work is the first one to explore a deep learning approach to predicting spatiotemporal distributions of the lake surface temperature (LST) in the Great Lakes. Our study shows that the Long Short-Term Memory (LSTM) neural network, trained with the limited data from hypothetical monitoring networks, can provide consistent and robust performance. The LSTM prediction captured the LST spatiotemporal variabilities across the five Great Lakes well, suggesting an effective and efficient way for monitoring network design in assisting the ML-based forecast. Furthermore, we employed an explainable artificial intelligence (XAI) technique named SHapley Additive exPlanations (SHAP) to uncover how the features impact the LSTM prediction. Our XAI analysis shows air temperature is the most influential feature for predicting LST in the trained LSTM. The relatively large bias in the LSTM prediction during the spring and fall was associated with substantial heterogeneity of air temperature during the two seasons. In contrast, the physics-based hydrodynamic model performed better in spring and fall yet exhibited relatively large biases during the summer stratification period. Finally, we developed a statistical integration of the hydrodynamic modeling and deep learning results based on the Best Linear Unbiased Estimator (BLUE). The integration further enhanced prediction accuracy, suggesting its potential for next-generation Great Lakes forecast systems. [ABSTRACT FROM AUTHOR]

We report on the angular and field dependence of the magnetoresistance (MR) in bilayers of Pt / EuO 1 − x thin films, measured in both in-plane and out-of-plane geometries at different temperatures (T). The presence of oxygen vacancies manifested by a metal–insulator transition as well as a high-T ferromagnet-to-paramagnet transition (TP) was observed in the bilayers. The anisotropic magnetoresistance could be extracted in the entire T-range, even above TP, exhibiting two sign crossovers. We attribute its T-evolution to the rotation of the easy axis of the magnetization direction from a high-T out-of-plane to a low-T in-plane orientation. In addition, we provide direct experimental evidence of the spin Hall effect-induced spin Hall magnetoresistance, systematically considering several known MR contributions that can arise from the films' (111) texture and interface. [ABSTRACT FROM AUTHOR]

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]

We present spin transport studies on a low-field, room-temperature magnetoelectric multiferroic polycrystalline Sr 3 Co 2 Fe 24 O 41 |Pt heterostructure wherein a highly tunable transverse conical magnetic phase is responsible for static and dynamic magnetoelectric coupling. We measured angular dependence of spin Hall magnetoresistance (SMR) at constant magnetic fields (H) in the range; 50–100 kOe. Application of field below the critical value (H c1 ≈ 2.5 kOe), yielded negative SMR and the H -evolution of normalized SMR ((Δ R ∕ R 0) × 100 %) exhibited a negative gradient. Further, an increase in H resulted in the positive slope of (Δ R ∕ R 0) × 100 % Vs. H and later at higher H around 14 kOe, a crossover from negative to positive SMR was observed. We employed a simple model for estimating the equilibrium magnetic configuration and computed the SMR modulation at various values of H. We argue that the tilting of the cone is dominant and in turn responsible for the observed nature of SMR below 2.5 kOe while, the closing of the cone-angle is pronounced at higher fields causing a reversal in sign of the SMR from negative to positive. Importantly, SMR experiments revealed that a change in the helicity with a reversal of the magnetic field has no influence on the observed SMR. Longitudinal spin Seebeck effect (LSSE) signal was measured to be ≈ 500 nV at 280 K, under application of thermal gradient, Δ T = 23 K and field, 60 kOe. The observed LSSE signal, originating from pure magnon spin current, showed a similar H -dependent behavior as that of the magnetization of Sr 3 Co 2 Fe 24 O 41. Our detailed spin transport studies on polycrystalline Sr 3 Co 2 Fe 24 O 41 |Pt heterostructure demonstrate high tunability of the amplitude and the sign of the SMR, highlighting its potential for novel spintronic devices such as SMR-based spin valves and voltage-controlled spin transport devices. [Display omitted] • Spin transport in room temperature multiferroic Z-type hexaferrite Sr 3 Co 2 Fe 24 O 41. • Spin Hall magnetoresistance as a probe for magnetic structure of Sr 3 Co 2 Fe 24 O 41. • Conical magnetic structure decides sign and amplitude of Spin Hall magnetoresistance. • Low-field tilting and high-field closing of the cones explain the spin transport. • Computation of Spin Hall magnetoresistance matches well with experiments. [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]

• We show enhanced spin transport in MgFe 2 O 4 thin films deposited on Si(100). • The spin current is thermally generated via the spin Seebeck effect (SSE). • Competing FM-AFM interactions manifest as a loop shift in standard hysteresis loops. • A distribution of anisotropy energies for the AFM could explain the results. We observe an exchange bias at low temperatures in polycrystalline ferrimagnetic MgFe 2 O 4 (MFO) films grown on Si(100), emerging from Antiferromagnetic (AFM)-like interactions at defect sites, concentrated predominantly at the grain boundaries. In this report, we show it is possible to utilize these AFM interactions to get enhanced spin transport utilizing the spin Seebeck effect (SSE). The temperature dependence of the SSE signal in two films with different defect densities allowed us to identify a unique temperature window for both films where an enhanced SSE signal was observed. Such enhancement has been reported in different Ferromagnet (FM)/AFM bilayer systems, but its observation in a single layer hosting both FM-AFM interactions makes our results attractive. Temperature dependent SQUID magnetometry revealed two distinct regions of strong and weak coupling for the FM-AFM interactions. The weak coupling region is characterized by a distribution of AFM energy barriers (Δ E), which can modify the spin conductance across the FM-AFM boundary and hence, affect the spin transport. Indeed, we find that the same functional form fits both the Δ E distribution and the SSE temperature evolution for both films. This study should aid in the understanding of SSE in the large class of polycrystalline materials with inherent growth induced defect densities and illustrate the significance of magnetically disordered phases in spin transport. [ABSTRACT FROM AUTHOR]

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]

Non-melanoma skin cancer of the head and neck (NMSCHN) is one of the most common malignancies worldwide, and its incidence is growing at a significant rate. It has been found to be aggressive in its spread and has the capacity to metastasize to regional lymph nodes. Cutaneous squamous cell carcinoma (cSCC) has a considerably high mortality rate. It has remarkable characteristics: diameter >2 cm, depth >5 mm, high recurrence, perineural invasion, and locoregional metastases. Aggressive cSCC lesions most commonly metastasize to the parotid gland. Also, immunocompromised patients have a higher risk of developing this aggressive cancer along with the worst prognostic outcomes. It is very important to discuss and assess the risk factors, prognostic factors, and outcomes of patients with cSCC, which will give clinicians future directives for making modifications to their treatment plans. The successful treatment of aggressive cSCC of the head and neck includes early detection and diagnosis, surgery alone or adjuvant chemotherapy, and radiotherapy as required. Multimodal therapy options should be considered by clinicians for better outcomes of aggressive cSCC of the head and neck. [ABSTRACT FROM AUTHOR]

Transportation cyber–physical systems (TCPSs) require simulation-based testing and evaluation due to the prohibitive cost of building realistic test beds. Given the transdisciplinary nature of TCPSs, various simulation models and frameworks have been proposed in civil engineering, computer science, and related fields. Traditionally, researchers in different areas have developed their own set of simulation tools, which provide limited capability for TCPS research. In recent years, we have witnessed a growing interest of combining two or more features of traditional simulators to capture the unique characteristics of TCPSs. In this paper, we describe several mainstream simulation models used in transportation, communication, and human-factor studies in TCPS research. Moreover, we present our unique design and implementation of an integrated traffic–driving–network simulator (ITDNS). Finally, we discuss future enhancements that will promote best simulation practices for TCPS research. [ABSTRACT FROM AUTHOR]

Double perovskite R 2 NiMnO 6 ( R =Pr, Nd, Tb, Ho and Y) composites are prepared via solid state synthesis or nitrate route. Isothermal magnetic entropy change ( Δ S M ( T , H ) ) and relative cooling power ( RCP ) for all systems are calculated and compared. All of them possess relatively high values of Δ S M ( T , H ) and RCP as compared to many perovskite and double perovskite systems reported previously. Ho 2 NiMnO 6 has the highest value for | Δ S M ( T , H ) | and RCP as 8.4 JKg − 1 K − 1 at 70 kOe and 59.18 J Kg −1 at 20 kOe respectively. This study highlights the potential of magnetocaloric refrigerant materials at low temperature. [ABSTRACT FROM AUTHOR]

Background: Engaging young adults for the purpose of communicating health risks associated with nicotine and tobacco use can be challenging since they comprise a population heavily targeted with appealing marketing by the evolving tobacco industry. The Food and Drug Administration seeks novel ways to effectively communicate risks to warn about using these products. This paper describes the first step in developing a text messaging program delivered by smartphones that manipulate three messaging characteristics (i.e., depth, framing, and appeal).Methods: Perceptions of community college students were described after previewing text messages designed to inform about risks of using conventional and new tobacco products. Thirty-one tobacco users and nonusers, aged 18-25 participated in five focus discussions held on two community college campuses. Attendees reviewed prototype messages and contributed feedback about text message structure and content. Qualitative data were coded and analyzed using NVivo Version 10.Results: Most participants were female and two-thirds were ethnic minorities. A variety of conventional and new tobacco products in the past month were used by a third of participants. Three identified domains were derived from the qualitative data. These included perceived risks of using tobacco products, receptivity to message content, and logistical feedback regarding the future message campaign.Conclusion: Overall, participants found the messages to be interesting and appropriate. A gap in awareness of the risks of using new tobacco products was revealed. Feedback on the prototype messages was incorporated into message revisions. These findings provided preliminary confirmation that the forthcoming messaging program will be appealing to young adults. [ABSTRACT FROM AUTHOR]

It is essential to consider drivers' perceptions and reactions when building Vehicular Cyber-Physical Systems (VCPS) since the effectiveness and efficiency of VCPS will largely depend on how drivers could benefit from such a system. This paper considers, for the first time, novel service scheduling problems from a Human Factors (HF) standpoint by taking into consideration the following fact: a driver may not be able to receive more than one service in a short period of time, even if multiple services can be transmitted to the driver from the conventional communications and networking standpoint. We study a family of the HF-aware Service Scheduling (HFSS) Problems, where the goal is to deliver up to n services, each having a time-dependent (and possibly decreasing) utility to a subset of intended drivers so as to minimize the system-wide total utility loss due to unsuccessful delivery of some services. We show that such problems are different from all existing problems. We formulate the basic HFSS problem (BHFSSP) using Integer Linear Programming (ILP) and prove its NP-Completeness. We then propose efficient heuristics for BHFSSP and its more general versions, and present numerical results from large-scale test cases. We also address several practical issues related to wireless transmission failures, distributed implementation in the multisender scenario, and other HF related considerations. [ABSTRACT FROM AUTHOR]