gebhart/patrepeval huggingface dataset:
Synthesis of Novel CuO Nanosheets and Their Non-Enzymatic Glucose Sensing Applications (2013)

In this study, we have developed a sensitive and selective glucose sensor using novel CuO nanosheets which were grown on a gold coated glass substrate by a low temperature growth method. X-ray differaction (XRD) and scanning electron microscopy (SEM) techniques were used for the structural characterization of CuO nanostructures. CuO nanosheets are highly dense, uniform, and exhibited good crystalline array structure. X-ray photoelectron spectroscopy (XPS) technique was applied for the study of chemical composition of CuO nanosheets and the obtained information demonstrated pure phase CuO nanosheets. The novel CuO nanosheets were employed for the development of a sensitive and selective non-enzymatic glucose sensor. The measured sensitivity and a correlation coefficient are in order 5.20 × 10² µA/mMcm² and 0.998, respectively. The proposed sensor is associated with several advantages such as low cost, simplicity, high stability, reproducibility and selectivity for the quick detection of glucose.
EXP-SA: A Lateral Field Excited Acoustic Wave Sensor for Peroxide-Based Explosives (2012)

Intellectual Merit:The candidate films will be functionalized on the quartz surface of the LFE sensing platform and exposed to peroxide-based IEDs and the materials used to fabricate them under simulated conditions. Critical sensor element properties such as the response level, response time, detection limit, resolution, and linearity will be measured and the selectivity will be determined by exposing the sensor to known concentrations of chemical simulants. In addition the admittance of each sensor element will be measured to isolate mechanical and electrical property changes in the film so as to identify the unique chemical signature of each analyte and provide a higher degree of selectivity. Sensor electronics will be designed and fabricated resulting in a handheld electronic unit. The sensor electronics will simultaneously process the output from five LFE sensing elements and provide a digital readout. Finally, the prototype sensor unit will be assembled and tested for the detection of PBEs and the materials commonly used to fabricate them.Broader Impacts:The development of a detector for PBEs will demonstrate that cutting edge research at the University of Maine will benefit homeland security, the military. A successful demonstration of a field deployable detector for PBEs will motivate the development and commercialization, by small sensor businesses, of similar sensors for homeland security, military, health, agricultural, automotive, and environmental applications.
Image Coding for Classification (1999)

Query by image contents is a successful approach to image database indexing and retrieval. Because image data take up huge amount of storage space and network bandwidth, compressing image is a standard practice. Given that images are compressed/coded in a database, it would be more efficient if the compressed data could also be directly used as indices for content-based query. The compressed data of traditional image coding/compression techniques such as the popular JPEG cannot be readily used to classify image contents. In this work, we set out to develop image coding schemes that will enable classification of image contents to be performed in the compressed domain without the need to perform image decoding and any extra processing. One of the novel features of this work is that we exploit some of the well known properties of human colour visual system for image representation. We outline a general scheme of colour image coding for classification and describe a specific implementation.
Electron energy-loss spectroscopy of electron states in isolated carbon nanostructures (2001)

Electronic states of an isolated nano-object made of single graphene layer have been successfully explored by means of electron energy-loss spectroscopy with high sensitivity and high spatial resolution. In further systematic study of various carbon nanostructures, the curvature and/or the interlayer coupling between adjacent graphene layers have been proved to govern the electronic states of carbon nanostructures. Using density functional theory, experimentally observed variations of the carbon $K(1s)$ near-edge fine structure have been ascribed mostly to the increasing curvature of the graphene layers.
Improving GPS-based landing system performance using an empirical barometric altimeter confidence bound (2008)

This paper develops an empirical confidence bound for barometric altimeter altitude errors and shows how this bound may improve the performance of GPS-based approach and landing systems. This empirical bound is developed using historical meteorological data collected at a set of geographically diverse locations over a thirty year period. The confidence bound developed is shown to provide a Gaussian overbound on altimeter altitude errors in standard atmospheric conditions between a 10-5 and 10-6 confidence level. This confidence bound is integrated into the standard methodology for analyzing the performance of GPS-based landing systems and the results of a performance trade study using the confidence bound are presented. The results show that incorporating the empirical barometric altimeter confidence bound provides an increase in the coterminous United States (CONUS) service volume for lateral precision with vertical guidance (LPV) type approaches. While this increase is approximately 2% for an L1 single-frequency GPS user, it jumps to roughly 40% for an L5 single-frequency user.
Trichloroethylene mineralization in a fixed-film bioreactor using a pure culture expressing constitutively tolueneortho -monooxygenase (1997)

An aerobic, single-pass, fixed-film bioreactor was designed for the continuous degradation and mineralization of gas-phase trichloroethylene (TCE). A pure culture of Burkholderia cepacia PR1(23)(TOM(23C)), a Tn5transposon mutant of B. cepacia G4 that constitutively expresses the TCE-degrading enzyme, toluene ortho-monooxygenase (TOM), was immobilized on sintered glass (SIRANtrade mark carriers) and activated carbon. The inert open-pore structures of the sintered glass and the strongly, TCE-absorbing activated carbon provide a large surface area for biofilm development (2-8 mg total cellular protein/mL carrier with glucose minimal medium that lacks chloride ions). At gas-phase TCE concentrations ranging from 0.04 to 2.42 mg/L of air and 0.1 L/min of air flow, initial maximum TCE degradation rates of 0.007-0.715 nmol/(min mg protein) (equivalent to 8.6-392.3 mg TCE/L of reactor/day) were obtained. Using chloride ion generation as the indicator of TCE mineralization, the bioreactor with activated carbon mineralized an average of 6.9-10.3 mg TCE/L of reactor/day at 0.242 mg/L TCE concentration with 0.1 L/min of air flow for 38-40 days. Although these rates of TCE degradation and mineralization are two- to 200-fold higher than reported values, TOM was inactivated in the sintered-glass bioreactor at a rate that increased with increasing TCE concentration (e.g., in approximately 2 days at 0.242 mg/L and <1 day at 2.42 mg/L), although the biofilter could be operated for longer periods at lower TCE concentrations. Using an oxygen probe and phenol as the substrate, the activity of TOM in the effluent cells of the bioreactor was monitored; the loss of TOM activity of the effluent cells corroborated the decrease in the TCE degradation and mineralization rates in the bioreactor. Repeated starving of the cells was found to restore TOM activity in the bioreactor with activated carbon and extended TCE mineralization by approximately 34%. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 55: 674-685, 1997.
NADPH Oxidase Subunit CYBB Confers Chemotherapy and Ferroptosis Resistance in Mesenchymal Glioblastoma via Nrf2/SOD2 Modulation (2023)

Glioblastoma multiforme (GBM) is a highly heterogeneous disease with a mesenchymal subtype tending to exhibit more aggressive and multitherapy-resistant features. Glioblastoma stem-cells derived from mesenchymal cells are reliant on iron supply, accumulated with high reactive oxygen species (ROS), and susceptible to ferroptosis. Temozolomide (TMZ) treatment is the mainstay drug for GBM despite the rapid development of resistance in mesenchymal GBM. The main interconnection between mesenchymal features, TMZ resistance, and ferroptosis are poorly understood. Herein, we demonstrated that a subunit of NADPH oxidase, CYBB, orchestrated mesenchymal shift and promoted TMZ resistance by modulating the anti-ferroptosis circuitry Nrf2/SOD2 axis. Public transcriptomic data re-analysis found that CYBB and SOD2 were highly upregulated in the mesenchymal subtype of GBM. Accordingly, our GBM cohort confirmed a high expression of CYBB in the GBM tumor and was associated with mesenchymal features and poor clinical outcome. An in vitro study demonstrated that TMZ-resistant GBM cells displayed mesenchymal and stemness features while remaining resilient to erastin-mediated ferroptosis by activating the CYBB/Nrf2/SOD2 axis. The CYBB maintained a high ROS state to sustain the mesenchymal phenotype, TMZ resistance, and reduced erastin sensitivity. Mechanistically, CYBB interacted with Nrf2 and consequently regulated SOD2 transcription. Compensatory antioxidant SOD2 essentially protected against the deleterious effect of high ROS while attenuating ferroptosis in TMZ-resistant cells. An animal study highlighted the protective role of SOD2 to mitigate erastin-triggered ferroptosis and tolerate oxidative stress burden in mice harboring TMZ-resistant GBM cell xenografts. Therefore, CYBB captured ferroptosis resilience in mesenchymal GBM. The downstream compensatory activity of CYBB via the Nrf2/SOD2 axis is exploitable through erastin-induced ferroptosis to overcome TMZ resistance.
Compressional- and shear-wave studies of distributed acoustic sensing acquired vertical seismic profile data (2017)

Abstract Understanding the strengths and limitations of rapidly advancing distributed acoustic sensing (DAS) technology used for recording vertical seismic profile (VSP) data is achieved by comparing DAS and geophone data sets using both compressional-wave (P-wave) and shear-wave (S-wave) VSP data and their corresponding geophysical answer products. We validate the kinematics (time) and dynamics (amplitude) of DAS VSP data by examining the extracted slowness values, response-to-incident angles, corridor stacks, and common-depth-point (CDP) transforms. For kinematics validation, the slowness values computed from P- and S-wave components of DAS VSP data agree with the geophone slowness values. For dynamics validation, we confirm the cos2θ response of the fiber to the incident angle of the seismic wavefield for P-waves and sin 2θ for S-waves. The amplitudes of the P-wave corridor stacks are comparable; the S-wave corridor stacks are similar for shallow events and differ for later events due to the limited response of the fiber to S-waves at near-vertical angles of incidence. High-quality CDP transform images are obtained for P- and S-waves. These analyses indicate that properly acquired DAS VSP data sets are reliable for the kinetics and dynamics of both P- and S-waves. Once the fiber-optic cable is installed in the well, VSP acquisition costs are greatly reduced because DAS data may be acquired with no additional well intervention. The extensive spatial coverage obtained using fiber-optic cables, the ease of acquiring time-lapse (4D) VSP data, and the reliability of the resulting DAS VSP data sets are making DAS technology an extremely important VSP acquisition tool.
Cover Picture: A Practical One‐Pot Synthesis of Positron Emission Tomography (PET) Tracers via Nickel‐Mediated Radiofluorination (ChemistryOpen 4/2015) (2015)

The cover picture shows the differences in brain metabolism of a healthy young and a healthy old subject, as well as a patient suffering from Parkinsons disease (left to right) uncovered by 6-[18F]FDOPA-positron emission tomography (PET). Morbus Parkinson occurs when nerve cells that produce dopamine begin to die. The shortage of dopamine leads to movement problems in affected individuals. 6-[18F]FDOPA is extensively used to evaluate the progression of Parkinsons disease. Bold stick projections of this PET tracer, as well as a neuronal network, are seen in the background. Unfortunately, conventional procedures to produce 6-[18F]FDOPA are cumbersome. Thus, several recent developments aim at the simplification of this radiosynthesis. In our work, we studied the applicability of the recently reported Ni-mediated radiofluorination approach for daily routine production of 6-[18F]FDOPA. For more details, see the Full Paper on p. 457 ff.
Commutation Technique for High-Frequency Link Cycloconverter Based on State-Machine Control (2005)

A technique for commutating the load current of a high-frequency link, pulse-width modulated cycloconverter is presented. As the load current makes a sign transition, switch operation becomes critical to avoid commutation failure. Previous techniques required either dead time or the use of large inductors to limit shoot-through current, thereby compromising performance and efficiency. The technique presented here identifies the switching sequence that is necessary to allow load current to commutate naturally without distortion. The switching sequence is managed with a state machine.
Preliminary systems engineering evaluations for the National Ecological Observatory Network. (2008)

The National Ecological Observatory Network (NEON) is an ambitious National Science Foundation sponsored project intended to accumulate and disseminate ecologically informative sensor data from sites among 20 distinct biomes found within the United States and Puerto Rico over a period of at least 30 years. These data are expected to provide valuable insights into the ecological impacts of climate change, land-use change, and invasive species in these various biomes, and thereby provide a scientific foundation for the decisions of future national, regional, and local policy makers. NEON's objectives are of substantial national and international importance, yet they must be achieved with limited resources. Sandia National Laboratories was therefore contracted to examine four areas of significant systems engineering concern; specifically, alternatives to commercial electrical utility power for remote operations, approaches to data acquisition and local data handling, protocols for secure long-distance data transmission, and processes and procedures for the introduction of new instruments and continuous improvement of the sensor network. The results of these preliminary systems engineering evaluations are presented, with a series of recommendations intended to optimize the efficiency and probability of long-term success for the NEON enterprise.
Coexistence of Localized and Delocalized Surface Plasmon Modes in Percolating Metal Films (2006)

Near-field intensity statistics in semicontinuous silver films over a wide range of surface coverage are investigated using near-field scanning optical microscopy. The variance of intensity fluctuations and the high-order moments of intensity enhancement exhibit local minima at the percolation threshold. This reduction in local field fluctuations results from resonant excitation of delocalized surface plasmon modes. By probing the modification of the critical indices for high-order moments of intensity enhancement caused by the delocalized states, we provide the first experimental evidence for the coexistence of localized and delocalized surface plasmon modes in percolating metal films.
EBV Latency II-derived Peptides Induce A Specific CD4+ Cytotoxic T-cell Activity and Not A CD4+ Regulatory T-cell Response (2012)

Epstein-Barr virus (EBV) is associated with several malignant diseases that can be distinguished by their patterns of viral latent gene expression. We developed here an original peptidic approach to favor the induction of a specific CD4+ T-cell response against EBV latency II malignancies (Hodgkin's lymphoma, nasopharyngeal carcinoma, T/NK lymphoma). Previously, we selected 6 peptides derived from EBV nuclear antigen-1, latency membrane proteins (LMP)-1, and LMP-2 highly promiscuous for major histocompatibility complex class II molecules and showed their ability to induce interferon-γ-secreting CD4+ T cells. We confirmed here that all peptides used in cocktail are recognized by human CD4+ memory T cells from healthy donors, inducing a broad T-helper (Th)1 cytokine secretion interferon-γ, interleukin-2. Furthermore, we have generated EBV-specific CD4+ T-cell lines and proved their cytotoxic potential, not only on original models expressing latency II antigens (EBV-transformed T cell or monocyte), but also on lymphoblastoid cell lines expressing latency III antigens (lymphoblastoid cell lines). In addition, granzyme B enzyme-linked immunospot assays suggested that a part of this specific cytotoxic activity could be linked to the granule lytic pathway. Very importantly, we have showed that neither phenotypical changes nor functional activities of CD4+CD25+CD127(low)-regulatory T cells were observed in response to EBV+ peptides, avoiding any risk of aggravation of the preexisting immunosuppressive environment reported in EBV-associated malignancies. In conclusion, our promiscuous peptide cocktail could be used safely in immunotherapeutic approaches against EBV latency II malignancies, mainly to prevent relapse in high-risk patients further to classic treatments.
Multifunctional chitosan magnetic-graphene (CMG) nanoparticles: a theranostic platform for tumor-targeted co-delivery of drugs, genes and MRI contrast agents (2013)

Combing chemotherapy with gene therapy has been one of the most promising strategies for the treatment of cancer. The noninvasive MRI with superparamagnetic iron oxide (SPIO) as contrast agent is one of the most effecitve techniques for evaluating the antitumor therapy. However, to construct a single system that can deliver efficiently gene, drug and SPIO to the cancer site remains a challenge. Herein, we report a chitosan functionalized magnetic graphene nanoparticle (CMG) platform for simultaneous gene/drug and SPIO delivery to tumor. The phantom and ex vivo MRI images suggest CMG as a strong T<sub>2</sub> contrast-enhancing agent. The CMGs are biocompatible as evaluated by the WST assay and predominantly accumulate in tumors as shown by biodistribution studies and MRI. The anticancer drug doxorubicin (DOX) loaded CMGs (DOX-CMGs) release DOX faster at pH 5.1 than at pH 7.4, and more effective (IC50 = 2 μM) in killing A549 lung cancer cells than free DOX (IC50 = 4 μM). CMGs efficiently deliver DNA into A549 lung cancer cells and C42b prostate cancer cells. In addition, i.v. administration of GFP-plasmid encapsulated within DOX-CMGs into tumor-bearing mice has showed both GFP expression and DOX accumulation at the tumor site at 24 and 48 hrs after administration. These results indicate CMGs provide a robust and safe theranostic platform, which integrates targeted delivery of both gene medicine and chemotherapeutic drug(s), and enhanced MR imaging of tumors. The integrated chemo- and gene- therapeutic and diagnostic design of CMG nanoparticles shows promise for simultaneous targeted imaging, drug delivery and real -time monitoring of therapeutic effect for cancer.
Time‐reversal imaging of seismic sources and application to the great Sumatra earthquake (2006)

The increasing power of computers and numerical methods (like spectral element methods) allows continuously improving modelization of the propagation of seismic waves in heterogeneous media and the development of new applications in particular time reversal in the three‐dimensional Earth. The concept of time‐reversal (hereafter referred to as TR) was previously successfully applied for acoustic waves in many fields like medical imaging, underwater acoustics and non destructive testing. We present here the first application at the global scale of TR with associated reverse movies of seismic waves propagation by sending back long period time‐reversed seismograms. We show that seismic wave energy is refocused at the right location and the right time of the earthquake. When TR is applied to the Sumatra‐Andaman earthquake (26 Dec. 2004), the migration of the rupture from the south towards the north is retrieved. Therefore, TR is potentially interesting for constraining the spatio‐temporal history of complex earthquakes.
High Temperature Stable W-GaAs Schottky Barrier (1982)

The effect of annealing a W-GaAs (Se + implanted) Schottky diode at high temperatures was investigated. The diode showed an excellent stability against annealing. The ideal factor n and the barrier height φ B of the diode stayed more or less constant at values of 1.1–1.2 and 0.73 V, respectively, for the temperature variation of 800°C–950°C. Using He + backscattering analysis, it was shown that the interdiffusion in W and GaAs couples takes place at 900°C.
Detecting privacy in attention aware system (2006)

Privacy and security are important issues for acceptation of ambient technology. For this reason, we propose a detector of relations between users and objects based on attention aware system. This detector is inspired by social sciences and completes the representation-driven model mainly used in ontology-based approaches. We discuss the role of context in these approaches and managing privacy. An attention model is derived from the gravitation model and cognitive psychology approaches. This model exploits contextual elements such as position, speed and saliency of objects in a scene to estimate shared attention. An application has been developed to demonstrate the efficiency of this system when managing windows applications, while guaranteeing the security and privacy of users. (9 pages)