gebhart/patrepeval huggingface dataset:
1/f Noise Characteristics of Waveguide-Integrated PbTe MIR Detectors and Impact on Limit of Detection (2021)

The noise power spectral density of a detector is essential for determining the frequency of operation and readout architecture that yields an optimal signal-to-noise ratio. In this work, we characterize a waveguide-integrated PbTe mid-infrared detector and report on its noise spectrum, highlighting the presence of a current-dependent 1/f term dominating at low frequency and/or high bias over the Johnson component typical of a photoconductor. This behaviour, together with the substantially flat frequency response in the range between 1 kHz to 1 MHz, guide towards a lock-in readout strategy, that allows one to operate in the region of minimum noise without penalties in the detection performance. Practical guidelines to optimize the readout resolution are provided and the limit of detection of a gas sensing system exploiting PbTe photoconductors is derived, as an example of how a careful co-design of sensors and electronics can dramatically improve the detection performance.
A broad-band single polarization optical fiber (1991)

The authors report on a single-mode optical fiber that transmits one and only one polarization state of the fundamental mode over a broad wavelength band (13%). The good broadband performance is attributed to the fiber's refractive-index profile, which mathematically allows only one polarization state to cutoff. The authors discuss general design principles and show that the mode field diameter is a qualitative indicator of the fiber's performance. The fiber's guided polarization state is similar to the fundamental mode of a step-index fiber in its low attenuation, 5.5 dB/km, and small mode diameter, 5.8 mu m (both measurements at 840 nm). Most important, the fiber shows a broad single polarization band, 13%, a feature well described by the change in mode field diameter with wavelength of an ideal, circularly symmetry, W-profile fiber.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>
Observing the Effects of Temperature and Surface Roughness on Cetyltrimethylammonium Bromide Adsorption Using a Quartz‐Crystal Microbalance with Dissipation Monitoring (2019)

Abstract The effects of temperature and surface roughness on the mass and viscoelasticity of an adsorbed surfactant layer were monitored using a quartz crystal microbalance with dissipation monitoring (QCM‐D). Adsorption isotherms at 30, 40, 50, and 60 °C and at two different roughnesses on gold were measured for cetyltrimethylammonium bromide (CTAB). All isotherms displayed an increase in mass and dissipation as surfactant concentration was increased to its critical micelle concentration (CMC). Above the CMC, adsorption reached a peak followed by a slight decrease to a plateau at the equilibrium adsorption value. As the temperature was increased, the adsorbed mass above the CMC decreased. The adsorbed mass decreased further by increasing substrate roughness, while the dissipation remained unchanged within experimental uncertainty. Dynamic adsorption experiments were also conducted at various temperatures for select concentrations above and below the CMC, providing evidence for the importance of different adsorption mechanisms as a function of both surfactant concentration and surface roughness.
The Cytokinin Complex Associated With Rhodococcus fascians: Which Compounds Are Critical for Virulence? (2019)

Virulent strains of <i>Rhodococcus fascians</i> cause a range of disease symptoms, many of which can be mimicked by application of cytokinin. Both virulent and avirulent strains produce a complex of cytokinins, most of which can be derived from tRNA degradation. To test the three current hypotheses regarding the involvement of cytokinins as virulence determinants, we used PCR to detect specific genes, previously associated with a linear virulence plasmid, including two methyl transferase genes (<i>mt1</i> and <i>mt2</i>) and <i>fas4</i> (dimethyl transferase), of multiple strains of <i>R. fascians</i>. We inoculated <i>Pisum sativum</i> (pea) seeds with virulent and avirulent strains of <i>R. fascians</i>, monitored the plants over time and compared these to mock-inoculated controls. We used RT-qPCR to monitor the expression of <i>mt1, mt2</i>, and <i>fas4</i> in inoculated tissues and LC-MS/MS to obtain a comprehensive picture of the cytokinin complement of inoculated cotyledons, roots and shoots over time. The presence and expression of <i>mt1</i> and <i>mt2</i> was associated with those strains of <i>R. fascians</i> classed as virulent, and not those classed as avirulent. Expression of <i>mt1, mt2</i>, and <i>fas4</i> peaked at 9 days post-inoculation (dpi) in cotyledons and at 15 dpi in shoots and roots developed from seeds inoculated with virulent strain 602. Pea plants inoculated with virulent and avirulent strains of <i>R. fascians</i> both contained cytokinins likely to have been derived from tRNA turnover including the 2-methylthio cytokinins and <i>cis</i>-zeatin-derivatives. Along with the isopentenyladenine-type cytokinins, the levels of these compounds did not correlate with virulence. Only the novel 1- and 2-methylated isopentenyladenine cytokinins were uniquely associated with infection by the virulent strains and are, therefore, the likely causative factors of the disease symptoms.
A Phase 2, Randomized, Double-Blind, Placebo-Controlled Study of GS-9450 in Subjects With Nonalcoholic Steatohepatitis (2011)

GS-9450 treatment induced significant reductions in ALT levels in NASH patients. Reductions in CK-18 fragment levels also occurred, although they were not statistically significant. At appropriate therapeutic indices, selective caspase inhibitors may be a promising treatment option in patients with NASH.
Strong, Ductile, and Waterproof Cellulose Nanofibril Composite Films with Colloidal Lignin Particles (2018)

Brittleness has hindered commercialization of cellulose nanofibril (CNF) films. The use of synthetic polymers and plasticizers is a known detour that impairs biodegradability and carbon footprint of the product. Herein, we utilize a variety of softwood Kraft lignin morphologies to obtain strong and ductile CNF nanocomposite films. An optimum 10 wt % content of colloidal lignin particles (CLPs) produced films with nearly double the toughness compared to a CNF film without lignin. CLPs rendered the films waterproof, provided antioxidant activity and UV-shielding with better visible light transmittance than obtained with irregular lignin aggregates. We conclude based on electron microscopy, dynamic water sorption analysis, and tp-DSC that homogeneously distributed CLPs act as ball bearing lubricating and stress transferring agents in the CNF matrix. Overall, our results open new avenues for the utilization of lignin nanoparticles in biopolymer composites equipped with versatile functionalities for applications in food packaging, water purification, and biomedicine.
In Vivo Characterization of the Swine Airway Morphometry and Motion Based on Computed Tomographic Imaging During Respiration (2020)

Swine are a commonly used model in translational pulmonary research. However, in vivo airway morphometry during respiration has not been studied in extensive detail using modern imaging tools. Chest computed tomographic was performed in swine (n = 3) at multiple stages of respiration. Morphometric parameters of each airway segment at end-expiration and end-inspiration were compared as well as among matched anatomical regions (proximal and distal; ventral, lateral, and dorsal). Analysis included segment diameter, length, ellipticity, and the bifurcation angle between daughter branches. Deformation of the airway during respiration was qualitatively visualized using a point-to-point deformation map. Comparison of airway generation showed airway diameter and length were larger at end-inspiration in the fourth and seventh generations compared to end-expiration. Bifurcation angle was larger at end-inspiration compared to end-expiration. Analysis by anatomical region showed that length and bifurcation angle were larger at inspiration in the distal airway regions only. Regardless of respiratory phase, the lateral regions had larger diameters and lengths compared to the ventral and dorsal regions at similar generations and proximal regions had larger bifurcation angles. The findings that morphological changes were more prevalent in distal airways during respiration was confirmed by analysis of a deformation map. Compared to human airway models, the relative diameter may be smaller and length may be greater in swine in similar airway generations. This morphometric description of the swine airways during respiration may guide conduct of preclinical translational studies, revealing advantages and limitations of swine models for specific evaluations. Such morphometric parameters may directly determine the suitability of the swine model for the study of lung interventions, in terms of recapitulation of human morphometry dynamics.
Live bacterial vaccine vectors: An overview (2014)

Genetically attenuated microorganisms, pathogens, and some commensal bacteria can be engineered to deliver recombinant heterologous antigens to stimulate the host immune system, while still offering good levels of safety. A key feature of these live vectors is their capacity to stimulate mucosal as well as humoral and/or cellular systemic immunity. This enables the use of different forms of vaccination to prevent pathogen colonization of mucosal tissues, the front door for many infectious agents. Furthermore, delivery of DNA vaccines and immune system stimulatory molecules, such as cytokines, can be achieved using these special carriers, whose adjuvant properties and, sometimes, invasive capacities enhance the immune response. More recently, the unique features and versatility of these vectors have also been exploited to develop anti-cancer vaccines, where tumor-associated antigens, cytokines, and DNA or RNA molecules are delivered. Different strategies and genetic tools are constantly being developed, increasing the antigenic potential of agents delivered by these systems, opening fresh perspectives for the deployment of vehicles for new purposes. Here we summarize the main characteristics of the different types of live bacterial vectors and discuss new applications of these delivery systems in the field of vaccinology.
Solvent control of selective ligand labilization in transition metal photochemistry (1977)

The ligand photolabilization of trans-[Fe(tim)-(CO)(MeCN)]2+(tim = 2,3,9,10-tetramethyl-1,4,8,11-tetra-azacyclotetradeca-1,3,8,10-tetraene) is controlled by the solvent with loss of CO occurring when the complex is photolysed in acetonitrile but loss of acetonitrile occurring when it is photolysed in acetone.
Structural Characterization of Poly(α-Fluoroacrylonitrile) and Poly(Ethyl α-Fluoroacrylate) (1994)

Abstract Monomers α-fluoroacrylonitrile (FAN) and ethyl α-fluoroacrylate (EFA) and homopolymers poly(α-fluoroacrylonitrile) (PFAN) and poly-(ethyl α-fluoroacrylate) (PEFA) have been synthesized and spectroscopi-cally characterized in detail for the first time. The 13C- and 19F-NMR spectroscopic results are reported, and the results are correlated to the tacticity and microstructure of both homopolymers. The major portion of the polymers is atactic. TGA analysis of PFAN indicates that the polymer is stable to about 200°C with subsequent loss of HF. PEFA is stable to 300 °C. Molecular weights determined by intrinsic viscosity (Mv ) are found to be about 130,000 for PFAN, and GPC analysis of PEFA indicates a molecular weight (Mn ) of about 36,000. Dielectric permittivities (ε) for PFAN and PEFA were determined to be 8.9 and 4.0, respectively, at 50 Hz.
400Gbit/s/ch Field Demonstration of Modulation Format Adaptation Based on Pilot-Aided OSNR Estimation Using Real-Time DSP (2017)

We describe a field experiment of flexible modulation format adaptation on a real-time 400Gbit/s/ch DSP-LSI. This real-time DSP-LSI features OSNR estimation, practical simplified back propagation, and high gain soft-decision forward error correction. With these techniques, we have successfully demonstrated modulation format allocation and transmission of 56-channel 400Gbit/s-2SC-PDM-16QAM and 200Gbit/s-2SC-PDM-QPSK signals in 216km and 3246km standard single mode fiber, respectively.
Global Humanitarian-based Projects: A Documentation Strategy for Strengthening Project Sustainability (2018)

Abstract International educational opportunities for engineering students include, but are not limited to, internships, study abroad programs, and humanitarian programs such as Engineers Without Borders (EWB). Since 2007, a two-semester Global Engineering Outreach (GEO) course in the College of Engineering and Technology at Brigham Young University has enabled engineering and technology students from multiple disciplines to design and implement humanitarian-based engineering projects. Energy, water, sanitation, and health projects have been implemented in Tonga, Ghana, and Peru. Currently, the projects focus on the needs of communities in Peru. Typically, nearly half of the students in the two-semester course speak and write Spanish fluently and have lived abroad in a Spanish-speaking country. This allows students to regularly engage with their Peruvian counterparts during the two semesters via phone and email exchanges on a near-weekly basis. An important aspect of the course during project development is the rigorous documentation of community engagement and product design. Effective documentation is critical for program sustainability, allowing for future students and instructors to assess past community engagement efforts, identify community engagement challenges, maintain information of past societal and technical design constraints, access concepts and prototypes previously assessed, and review videos documenting community and project information. This paper will address a documentation strategy used in the GEO course in which the documentation is updated on a regular basis throughout the design process, leading to a large database for all implemented projects. The documentation is composed of project management, community communication and engagement, technical and social constraints, concept and prototype development, testing and evaluation, finances, project design, project implementation, and project maintenance. In addition, extensive video documentation is also included. Finally, this paper will also address assessment related to the effectiveness of community engagement, providing insights on how to improve program sustainability.
Mechanical loads at the knee joint during deep flexion (2002)

There is a lack of fundamental information on the knee biomechanics in deep flexion beyond 90 degrees. In this study, mechanical loads during activities requiring deep flexion were quantified on normal knees from 19 subjects, and compared with those in walking and stair climbing. The deep flexion activities generate larger net quadriceps moments (6.9-13.5% body weight into height) and net posterior forces (58.3-67.8% body weight) than routine ambulatory activities. Moreover, the peak net moments and the net posterior forces were generated between 90 degrees and 150 degrees of flexion. The large moments and forces will result in high stress at high angles of flexion. These loads can influence pathological changes to the joint and are important considerations for reconstructive procedures of the knee. The posterior cruciate ligament should have a substantial role during deep flexion, since there was a large posterior load that must be sustained at the knee. The mechanics of the knee in deep flexion are likely a factor causing problems of posterior instability in current total knee arthroplasty. Thus, it is important to consider the magnitude of the loads at the knee in the treatment of patients that commonly perform deep flexion during activities of daily living.
Distributed massive MIMO in cellular networks: Impact of imperfect hardware and number of oscillators (2015)

Distributed massive multiple-input multiple-output (MIMO) combines the array gain of coherent MIMO processing with the proximity gains of distributed antenna setups. In this paper, we analyze how transceiver hardware impairments affect the downlink with maximum ratio transmission. We derive closed-form spectral efficiencies expressions and study their asymptotic behavior as the number of the antennas increases. We prove a scaling law on the hardware quality, which reveals that massive MIMO is resilient to additive distortions, while multiplicative phase noise is a limiting factor. It is also better to have separate oscillators at each antenna than one per BS.
Cross talk between friction and height signals in atomic force microscopy (2002)

Atomic force and lateral force microscopes use a four quadrant p-i-n detector to measure the motion of a laser beam reflected from the top of a cantilever. If the detector is rotated slightly in the plane of the p-i-n diode, this will cause frictional forces to be detected as a false height signal. In this article, we will show how this coupling between friction and height signals can adversely affect the measurement of topology at height scales below 10 nm. This will be demonstrated with contact mode images of single-walled carbon nanotubes. We will also show how to detect this effect and possible ways to correct for it.
Cancer Vaccines in Phase II/III Clinical Trials: State of the Art and Future Perspectives (2010)

The topic of this review covers a very important branch of cancer research, cancer vaccination. The growing knowledge in tumor immunology has evolved rapidly, starting from nonspecific generic stimulation of the immune system to more specific approaches based on the availability of tumor antigens. The review covers molecular and cell biology, and pharmaceutical technology of cancer vaccines. Particularly, it is aimed at highlighting the results of cancer vaccines from phase II and III clinical trials, an issue that is of relevance to better understand how cancer vaccines can successfully complement antitumor therapy, including conventional chemotherapy and the recently developed target-based drugs.
Alkaline Chemical Stability and Ion Transport in Polymerized Ionic Liquids with Various Backbones and Cations (2016)

The development of anion exchange membranes (AEMs) with high alkaline chemical stability, as well as high ion conductivity, is crucial to the implementation of long-lasting, low-cost (nonplatinum) alkaline fuel cells (AFCs). In this study, 12 polymerized ionic liquids (PILs) were synthesized with various backbones and cations (backbones: ethyl methacrylate, undecyl methacrylate, undecyl acrylate, styrene; covalently attached cations: butylimidazolium, trimethylammonium, butylpyrrolidinium). 1H NMR spectroscopy was employed to determine the alkaline degradation mechanisms and extent of degradation at high pH (in D2O) at 60 °C for 1 week (168 h). For the butylpyrrolidinium cation, ethyl and undecyl methacrylate backbones proved to be more stable than the undecyl acrylate backbone. Styrene (vinylbenzene) functionalized with butylpyrrolidinium cation surpassed the stability of the benchmark benzyltrimethylammonium (BTMA) cation, where the former possessed the highest overall observed chemical stability with 0% degradation after 1 week in 20 mol equiv of KOH at 60 °C. This butylpyrrolidinium styrene-based PIL, poly(VBBP-Br), also had a high bromide conductivity of 14.5 mS cm–1 at 60 °C and 90% relative humidity. Additionally, poly(VBBP-Br) achieved the desirable AEM properties of relatively low water uptake (hydration number = 5.6 mol H2O/mol cation) at high ion exchange capacity (IEC = 4.1 mmol g–1). The styrene/butylpyrrolidinium pairing offers several advantages over the popular styrene/BTMA pairing (e.g., higher conductivity, higher chemical stability, lower water uptake), while similarly to BTMA, allows for facile functionalization that is easily incorporated into existing AEM styrene backbones. Overall, these results show the promise and practicality of the butylpyrrolidinium styrene-based AEM chemistry for AFC applications.
Molecular Dynamics Simulation of Alkane in a pore of Activated Carbon (2000)

Adsorption behavior of alkane in a pore of activated carbon was investigated by molecular dynamics simulation. Two models of carbon wall were presented based on graphitizing and non-graphitizing shapes of micropore. An adsorbate of dodecane was dealt with where methyl and methylene were treated as cluster particles having all internal degree of freedom. The Lennard-Jones potential was used for non-bonded interaction. While potentials due to bond stretches, angle bends and periodical torsion were included to describe the interaction among neighboring particles inside the dodecane. The dynamic adsorption process, and the adsorption energy of dodecane-carbon system were calculated. The influences on the adsorption behavior of pore size and shape of activated carbon were discussed.
Galaxy content of the Hydra I and Fornax clusters of galaxies (1980)

The determination of the fractional population of spirals and ellipticals in the centrally concentrated Hydra I and irregular Fornax galaxy clusters shows that the number of spiral-like structures depends on the surface brightness interval considered. The spiral content of Hydra I is similar to color studies of distant concentrated clusters; the less dense Fornax cluster has a larger spiral content and more normal spirals. The majority of low brightness and dwarf galaxies have an elliptical distribution suggesting their causal relationship.
Remarkable Dendritic Effect in the Polymer-Supported Catalysis of the Heck Arylation of Olefins (2003)

[reaction: see text] Phosphine-palladium complexes, immobilized on polystyrene, demonstrated a remarkable increase in catalytic activity and selectivity in the Heck reaction upon the introduction of a dendritic spacer between the support and phosphine. For some reactions an up to 5-fold increase in yield is observed.
Novel Results and Concepts Emerging From Lipid Cell Biology Relevant to Degenerative Brain Aging and Disease (2019)

While very rare familial forms of proteinopathy can cause Parkinson's disease (PD), Lewy body dementia (LBD) and age-related dementias, recent in-depth studies of lipid disturbances in the majority of the common forms of these diseases instead suggest a primary pathogenesis in lipid pathways. This review synthesizes a perspective from new data that point to an interdependence of lipids and proteinopathy. This article describes disturbed relationships in lipid homeostasis that causes neuropathology to develop over time and with age, which includes altered mechanisms of glia-neuron exchange of lipids and inflammatory signals.
Tumor necrosis of primary malignancy affects survival and outcome in patients with liver metastases from neuroendocrine tumors (2018)

Question. Reliable biomarkers represent a crucial unmet need in the management of neuroendocrine tumors. Histologic tumor necrosis has been suggested to have a prognostic value in selected solid tumors but is not included in established WHO NET Grading Systems. However, little is known regarding the influence of tumor necrosis on tumor progression and prognosis in patients with liver metastasis from neuroendocrine tumors.
ChemInform Abstract: Efficient, Regioselective Palladium‐Catalyzed Tandem Heck‐Isomerization Reaction of Aryl Bromides and Non‐Allylic Benzyl Alcohols. (2009)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.