gebhart/patrepeval huggingface dataset:
Highly-nonlinear quantum-engineered polaritonic metasurfaces (2015)

Intersubband transitions in n-doped semiconductor heterostructures allow one to quantum-engineer one of the largest known nonlinear response in condensed matter systems but only for the electric field polarized normal to semiconductor layer. By coupling of a quantum-engineered multi-quantum-well semiconductor layer with electromagnetically-engineered plasmonic elements we may produce ultrathin metasurfaces with giant nonlinear response. Here we experimentally demonstrate metasurfaces designed for second harmonic generation at ??&amp;#8776;9.9 ??m with a record-high nonlinear response for condensed-matter systems in infrared/visible spectral range, up to 1.17??106 pm/V. The practical impact of the nonlinear metasurfaces proposed here may be extended to a variety of fields, including THz generation and detection, phase conjugation, and other nonlinear optical processes.
SUPC: SDN enabled Universal Policy Checking in Cloud Network (2019)

Multi-tenant cloud networks have various security and monitoring service functions (SFs) that constitute a service function chain (SFC) between two endpoints. SF rule ordering overlaps and policy conflicts can cause increased latency, service disruption and security breaches in cloud networks. Software Defined Network (SDN) based Network Function Virtualization (NFV) has emerged as a solution that allows dynamic SFC composition and traffic steering in a cloud network. We propose an SDN enabled Universal Policy Checking (SUPC) framework, to provide 1) Flow Composition and Ordering by translating various SF rules into the OpenFlow format. This ensures elimination of redundant rules and policy compliance in SFC. 2) Flow conflict analysis to identify conflicts in header space and actions between various SF rules. Our results show a significant reduction in SF rules on composition. Additionally, our conflict checking mechanism was able to identify several rule conflicts that pose security, efficiency, and service availability issues in the cloud network.
Design Of A New In Situ Spectroscopic Phase Modulated Ellipsometer (1990)

A new spectroscopic phase modulated ellipsometer (SPME) is presented. As compared to other ellipsometric techniques like rotating analyzer ellipsometry (RAE), the phase modulation uses a high frequency modulation (50 kHz) provided by a photoelastic modulator. Then SPME allows at least two orders of magnitude faster real-time mesurements than RAE. Thus, SPME is particularly suitable for in situ real-time applications. New insights on phase modulated ellipsometry are given. In particular, it is shown that an optical model, taking into account the presence of higher harmonics in the modulation, leads to an improvement of the precision measurement. Therefore, it can be inferred that both RAE and SPME provide comparable high precision measurements. Moreover SPME can be combined with numerical data processing systems. A new Fourier analysis of the signal, based on the use of a high precision analog digital converter and a fast digital processor, is presented. The adaptation of the SPME to a deposition chamber is illustrated. In particular, the use of optical fibers in both optical arms allows an increase of the compactness of the ellipsometer. Four detectors can be used simultaneously providing the spectroscopic capability for real-time applications. On-line connexions between the data acquisition system and external analog signals and triggers can also be used. Thus phase modulated ellipsometry appears a powerful technique for in situ control processing applications.
Laser optoacoustic tomography for medical diagnostics: principles (1996)

This paper is to describe principles of laser optoacoustic tomography for medical diagnostics. Two types of imaging modes are presented. The first is the tomography in transmission mode, which utilizes detection of stress transients transmitted from the laser-excited volume toward the depth through thick layers of tissue. The second is the tomography in reflection mode which utilizes detection of stress transients generated in superficial tissue layer and reflected back toward tissue surface. To distinguish the two modes, we have abbreviated them as (1) laser optoacoustic tomography in transmission mode, LOATT, and (2) time-resolved stress detection tomography of light absorption, TRSDTLA, in reflection mode where emphasis is made on high spatial resolution of images. The basis for laser optoacoustic tomography is the time-resolved detection of laser-induced transient stress waves, selectively generated in absorbing tissues of diagnostic interest. Such a technique allows one to visualize absorbed light distribution in turbid biological tissues irradiated by short laser pulses. Laser optoacoustic tomography can be used for detection of tissue pathological changes that result in either increased concentration of various tissue chromophores such as hemoglobin or in development of enhanced microcirculation in diseased tissue. Potential areas of applications are diagnosis of cancer, brain hemorrhages, arterial atherosclerotic plaques, and other diseased tissues. In addition, it can provide feedback information during medical treatments. Both LOATT and TRSDTLA utilize laser excitation of biological tissues and sensitive detection of laser-induced stress waves. Optical selectivity is based upon differences in optical properties of pathologically different tissues. Sensitivity comes from stress generation under irradiation conditions of temporal stress confinement. The use of sensitive wide-band lithium niobate acoustic transducers expands limits of laser optoacoustic tomography. The technology allows us to determine directly temperature distributions in tissues and locate tissues volumes with different absorption. To demonstrate principles of TRSDTLA, experiments were conducted in vivo with mice-model for breast cancer using specially designed front-surface transducers- reflectometers. To present advantages and limitation of LOATT, experiments were performed in phantoms made of gel with polystyrene spheres colored with copper sulfate. Our experimental results and theoretical calculations show that TRSDTLA can be applied for non- invasive histology of layered tissues with in-depth resolution of up to 2 microns. TRSDTLA in acoustic reflection mode is promising for diagnostics of skin and ocular diseases. LOATT in acoustic transmission mode can be applied for detection of small tissue volumes with enhanced absorption located inside organs at the depth of up to 10 cm.
Metabolic engineering of Escherichia coli for the production of 1,3-diaminopropane, a three carbon diamine (2015)

Bio-based production of chemicals from renewable resources is becoming increasingly important for sustainable chemical industry. In this study, Escherichia coli was metabolically engineered to produce 1,3-diaminopropane (1,3-DAP), a monomer for engineering plastics. Comparing heterologous C4 and C5 pathways for 1,3-DAP production by genome-scale in silico flux analysis revealed that the C4 pathway employing Acinetobacter baumannii dat and ddc genes, encoding 2-ketoglutarate 4-aminotransferase and L-2,4-diaminobutanoate decarboxylase, respectively, was the more efficient pathway. In a strain that has feedback resistant aspartokinases, the ppc and aspC genes were overexpressed to increase flux towards 1,3-DAP synthesis. Also, studies on 128 synthetic small RNAs applied in gene knock-down revealed that knocking out pfkA increases 1,3-DAP production. Overexpression of ppc and aspC genes in the pfkA deleted strain resulted in production titers of 1.39 and 1.35 g l(-1) of 1,3-DAP, respectively. Fed-batch fermentation of the final engineered E. coli strain allowed production of 13 g l(-1) of 1,3-DAP in a glucose minimal medium.
A Three-Stage Mechanistic Model for Ammonia–Borane Dehydrogenation by Shvo’s Catalyst (2012)

We propose a mechanistic model for three-stage dehydrogenation of ammonia borane (AB) catalyzed by Shvo's cyclopentadienone-ligated ruthenium complex. We provide evidence for a plausible mechanism for catalyst deactivation, the transition from fast catalysis to slow catalysis, and relate those findings to the invention of a second-generation catalyst that does not suffer from the same deactivation chemistry.The primary mechanism of catalyst deactivation is borazine-mediated hydroboration of the ruthenium species that is the active oxidant in the fast catalysis case. This transition is characterized by a change in the rate law for the reaction and changes in the apparent resting state of the catalyst. Also, in this slow catalysis situation, we see an additional intermediate in the sequence of boron, nitrogen species, aminodiborane. This occurs with concurrent generation of NH(3), which itself does not strongly affect the rate of AB dehydrogenation.
The pressure differential particle detector: its capabilities as compared to the acoustical particle detector (1981)

A new detector of airborne particles is presented. Its design and capabilities are compared to those of a similar device, the acoustical particle detector. The new device, called a pressure differential particle detector (PDPD), detects particles by a momentary change in static pressure as opposed to acoustical detection. This pressure change accompanies a particle passage through the detector's orifice and occurs in the detector's exit chamber. Unlike the acoustical particle detector, replicate models of the PDPD are easily fabricated. The PDPD also posseses improved small particle detection efficiencies and improved particle sizing capabilities. In this regard, the PDPD possesses pulse amplitude size discriminating capabilities as well as the flow dependent size discriminating capabilities of the acoustical detector. A limitation shared by both particle detectors is their relative insensitivity to particle sizes in the respirable range.
An automated multiviewing ultrasonic technique for flaw reconstruction (1987)

This paper describes key achievements in the development of an automated multiviewing ultrasonic instrumentation for flaw characterization in materials. Based on ultrasonic signals scattered from the flaw in a number of directions, the signal processing algorithms provide a reconstruction of the size, shape, and orientation of the flaw. To improve the reconstruction reliability for arbitrarily oriented flaws, an angular scan plan is developed to select the most favorable data acquisition aperture configuration for a given flaw. Reconstruction results are presented. Electronic circuits are developed for the generation and detection of broadband unipolar ultrasonic pulses in order to characterize flaws over a wider size range. A second generation multiview transducer has been developed to incorporate these capabilities. The instrumentation and the associated signal processing algorithms form a unique research and inspection tool. 17 refs., 6 figs., 1 tab.
Simultaneous multinuclear magnetic resonance imaging and spectroscopy (1991)

A technique has been developed to perform simultaneous multinuclear magnetic resonance imaging and spatially localized spectroscopy. It is inherently superior in terms of time efficiency over current approaches which use sequential or interleaved methods. The pulse sequence uses a parallel excitation and acquisition scheme to acquire multislice proton images concurrently with phosphorus-31 spectroscopic images. Because the phosphorus signal is necessarily collected in the presence of a gradient, an essential element of the technique is an algorithm to extract pure chemical-shift information.
Proposal for peltier current lead and FGM for current lead of superconducting magnet system. (1996)

The current lead is a key component in a superconducting magnet system. Yet heat conduction and ohmic heating of the current lead should be kept to a minimum for economic reasons and for the cryogenic stability of the system. High temperature superconducting materials (HTS) has recently been used to solve the contradiction in the current lead. A third generation current lead, called the Peltier current lead, is described. The Peltier current elementis a heat pump made of N-type and P-type semiconductors. The technology of the Peltier element can be applied with HTS current lead. Experiments with the Peltier current lead demonstrate the reduction of heat leak of 15 to 25%. Since the HTS and the semiconductor are made from Bi-based materials, for exapmle, Bi-2223 for HTS and BiTe (Sb) for the semiconductor, we might made a whole current lead from Bi-based material, and this is one of the functionally gradient material (FGM).
Mitogenic function of human procathepsin D: the role of the propeptide (1994)

The proform of cathepsin D is secreted by some human breast-cancer cell lines upon stimulation with oestrogen. In these cell lines, procathepsin D was described to act as an autocrine mitogen, and a correlation between the cathepsin D concentration in tumour tissues and poor prognosis for the patient was demonstrated in several independent investigations. In the present study, we focused on the mechanism of procathepsin D mitogenic activity. Procathepsin D isolated from secretions of ZR-75-1 breast-cancer cell line was used to test for mitogenic activity on a set of seven human cell lines. For nanomolar procathepsin D concentrations, we found a stronger dose-responsive cellular reaction in the case of several different human breast-cancer-derived cell lines. The mitogenic activity was not blocked by the inhibition of proteolytic activity nor by the inhibition of the interaction of procathepsin D with mannose-6-phosphate receptors. On the other hand, the addition of antibodies raised against the propeptide impaired the mitogenic activity of procathepsin D, and a synthetic peptide alone corresponding to the propeptide of procathepsin D produced similar effects, as did the zymogen molecule. The synthetic propeptide was shown to block partially the interaction of procathepsin D with the cellular surface. Our results indicate that the mitogenic function involves the propeptide of cathepsin D, which appears to be recognized by a surface receptor.
Routing, Wavelength Assignment, and Spectrum Allocation in Transparent Flexible Optical WDM (FWDM) Networks (2010)

We propose the flexible optical WDM network architecture, and introduce the routing, wavelength assignment, and spectrum allocation problem in transparent FWDM networks. Spectrum and cost efficiency are improved compared to fixed grid networks.
Catalytic Ethylene Dimerization and Oligomerization:  Recent Developments with Nickel Complexes Containing P<i>,</i>N-Chelating Ligands (2005)

Catalytic ethylene oligomerization represents a topic of considerable current academic and industrial interest, in particular for the production of linear alpha-olefins in the C4-C10 range, whose demand is growing fast. Identifying and fine-tuning the parameters that influence the activity and selectivity of metal catalysts constitute major challenges at the interface between ligand design, coordination/organometallic chemistry, and homogeneous catalysis. In this Account, we show how comparative studies aiming at modulating the coordinating properties of functional ligands for a metal, such as nickel, which is used in industrial processes, lead to beneficial effects in catalytic ethylene oligomerization.
Efficient Synthesis of Amine-Linked 2,4,6-Trisubstituted Pyrimidines as a New Class of Bacterial FtsZ Inhibitors (2017)

We have recently identified a new class of filamenting temperature-sensitive mutant Z (FtsZ)-interacting compounds that possess a 2,4,6-trisubstituted pyrimidine-quinuclidine scaffold with moderate antibacterial activity. Employing this scaffold as a molecular template, a compound library of amine-linked 2,4,6-trisubstituted pyrimidines with 99 candidates was successfully established by employing an efficient convergent synthesis designed to explore their structure-activity relationship. The results of minimum inhibitory concentration (MIC) assay against <i>Staphylococcus aureus</i> strains and cytotoxicity assay against the mouse L929 cell line identified those compounds with potent antistaphylococcal properties (MIC ranges from 3 to 8 μg/mL) and some extent of cytotoxicity against normal cells (IC<sub>50</sub> ranges from 6 to 27 μM). Importantly, three compounds also exhibited potent antibacterial activities against nine clinically isolated methicillin-resistant <i>S. aureus</i> (MRSA) strains. One of the compounds, <b>14av_amine16</b>, exhibited low spontaneous frequency of resistance, low toxicity against <i>Galleria mellonella</i> larvae, and the ability to rescue <i>G. mellonella</i> larvae (20% survival rate at a dosage of 100 mg/kg) infected with a lethal dose of MRSA ATCC 43300 strain. Biological characterization of compound <b>14av_amine16</b> by saturation transfer difference NMR, light scattering assay, and guanosine triphosphatase hydrolysis assay with purified <i>S. aureus</i> FtsZ protein verified that it interacted with the FtsZ protein. Such a property of FtsZ inhibitors was further confirmed by observing iconic filamentous cell phenotype and mislocalization of the Z-ring formation of <i>Bacillus subtilis</i>. Taken together, these 2,4,6-trisubstituted pyrimidine derivatives represent a novel scaffold of <i>S. aureus</i> FtsZ inhibitors.
A magnetostrictive force sensor (1994)

A new magnetostrictive force sensor is presented and its operation is verified experimentally. The sensor has a single excitation coil and a single detection coil, which utilize the magnetostrictive effect. The cores of the coils function as ‘‘spring elements’’ of the sensor, and are linked together by rigid end plates. The magnetostrictive force sensor is compensated for asymmetric magnetostrictive behavior, and measures both tensile and compressive forces. Force sensitivity increases with excitation current and coil turns, but is less influenced by excitation frequency.
A Molecular Basis for Stabilization of the von Hippel-Lindau (VHL) Tumor Suppressor Protein by Components of the VHL Ubiquitin Ligase (2002)

The multiprotein von Hippel-Lindau (VHL) tumor suppressor (CBC(VHL), Cul2-Elongin BC-VHL) and SCF (Skp1-Cul1/Cdc53-F-box protein) complexes are members of structurally related families of E3 ubiquitin ligases that use a heterodimeric module composed of a member of the Cullin protein family and the RING finger protein Rbx1 (ROC1/Hrt1) to activate ubiquitylation of target proteins by the E2 ubiquitin-conjugating enzymes Ubc5 and Cdc34. VHL and F-box proteins function as the substrate recruitment subunits of CBC(VHL) and SCF complexes, respectively. In cells, many F-box proteins are short lived and are proposed to be ubiquitylated by an autocatalytic mechanism and destroyed by the proteasome following assembly into SCF complexes. In contrast, the VHL protein is stabilized by interaction with the Elongin B and C subunits of CBC(VHL) in cells. In this report, we have presented direct biochemical evidence that unlike the F-box protein Cdc4, which is ubiquitylated in vitro by Cdc34 in the context of the SCF, the VHL protein is protected from Ubc5-catalyzed ubiquitylation following assembly into the CBC(VHL) complex. CBC(VHL) is continuously required for negative regulation of hypoxia-inducible transcription factors in normoxic cells and of SCF complexes, many of which function only transiently during the cell cycle or in response to cellular signals. Our findings provide a molecular basis for the different modes of cellular regulation of VHL and F-box proteins and are consistent with the known roles of CBC(VHL).
In situ 3D reconfigurable ultrasonically sculpted optical beam paths (2019)

We demonstrate that optical beams can be spatially and temporally shaped in situ by forming 3D reconfigurable interference patterns of ultrasound waves in the medium. In this technique, ultrasonic pressure waves induce a modulated refractive index pattern that shapes the optical beam as it propagates through the medium. Using custom-designed cylindrical ultrasonic arrays, we demonstrate that complex patterns of light can be sculpted in the medium, including dipole and quadrupole shapes. Additionally, through a combination of theory and experiment, we demonstrate that these optical patterns can be scanned in radial and azimuthal directions. Moreover, we show that light can be selectively confined to different extrema of the spatial ultrasound pressure profile by temporally synchronizing lightwave and ultrasound. Finally, we demonstrate that this technique can also be used to define spatial patterns of light in turbid media. The notion of in situ 3D sculpting of optical beam paths using ultrasound interference patterns can find intriguing applications in biological imaging and manipulation, holography, and microscopy.
Metabolomic stability of exercise-induced sweat (2019)

Due to increased interest in the use of excreted sweat for biomarker discovery, data must be generated supporting sample collection and handling methods to allow for controlled, large-scale biomarker discovery studies to be performed. In this manuscript, twelve amino acids were quantitated from exercise-induced excreted sweat held at room temperature or a simulated body temperature of 37 °C for up to 90 min. The data illustrate a large dynamic range exists among amino acids in sweat. Additionally, the amino acid quantities vary across individuals and among the same individual under different storage conditions, with alanine, arginine, and threonine showing a significant statistical difference between sampling events (p < 0.05). Furthermore, the results establish amino acids are relatively invariant, at both storage temperatures tested, for up to 90 min illustrated by <10% (15/156) of the amino acids measurements demonstrating change greater than 10% from the time zero value. An untargeted metabolomics approach was also applied to the data set to evaluate global changes to the metabolome. The results show more than 88% of all data points fall within the established limits, regardless of temperature condition and ionization mode. Collectively, this study demonstrates that sweat is largely invariant at two distinct temperatures for up to 90 min. These results establish sweat collection and sample handling is possible for up to 90 min with minimal changes in metabolite abundances.