gebhart/patrepeval huggingface dataset:
Mutational biosynthesis of a new antibiotic, streptomutin A, by an idiotroph of Streptomyces griseus. (1975)

Microorganisms producing antibiotics have been genetically converted by earlier workers to mutants which cannot produce antibiotic without supplementation with a moiety of the antibiotic. These antibiotics include neomycin, kanamycin, paromomycin, butirosin, sisomicin, ribostamycin and novobiocin. Success has not been reported for organisms producing guanidinocyclitol antibiotics such as streptomycin. We mutagenized conidia of the streptomycin-producing Streptomyces griseus strain 7-455F3 with nitrosoguanidine at pH 7.0. Non-producers of streptomycin were visually selected by the agar-plug technique using Bacillus subtilis. We successfully isolated mutant MIT-A5 which produces no streptomycin unless streptidine is added to the agar medium. The streptidine-dependent phenotype was confirmed in submerged culture in flasks. Attempts to produce new antibiotics by feeding aminocyclitols to mutant MIT-A5 failed. However a new antibiotic (streptomutin A) was produced by supplementation with the guanidinocyclitol, 2-deoxystreptidine. We propose the term "mutational biosynthesis" for the production of new metabolites by the use of mutants blocked in the biosynthetic pathway to the secondary metabolite. We further propose the term "idiotroph" to properly describe such mutants.
RADIORECEPTOR ASSAY OF HUMAN CHORIONIC GONADOTROPIN: DETECTION OF EARLY PREGNANCY (1974)

Division of Endocrinology, Department of Medicine, Cornell University Medical College, New York 10021
Room temperature hyperpolarization of nuclear spins in bulk (2014)

Dynamic nuclear polarization (DNP), a means of transferring spin polarization from electrons to nuclei, can enhance the nuclear spin polarization (hence the NMR sensitivity) in bulk materials at most 660 times for (1)H spins, using electron spins in thermal equilibrium as polarizing agents. By using electron spins in photo-excited triplet states instead, DNP can overcome the above limit. We demonstrate a (1)H spin polarization of 34%, which gives an enhancement factor of 250,000 in 0.40 T, while maintaining a bulk sample (∼ 0.6 mg, ∼ 0.7 × 0.7 × 1 mm(3)) containing >10(19) (1)H spins at room temperature. Room temperature hyperpolarization achieved with DNP using photo-excited triplet electrons has potentials to be applied to a wide range of fields, including NMR spectroscopy and MRI as well as fundamental physics.
Influence of pH‐Induced Unfolding and Refolding of Egg Albumen on Its Foaming Properties (2005)

ABSTRACT: The foaming properties of egg albumen, which had been subjected to low and high pH unfolding followed by refolding, were investigated. The foaming capacity of egg albumen, the stability of the foam, or both, could be improved by an unfolding and refolding regime by choosing proper unfolding and refolding pH values. The foaming capacities of egg albumen were greatly improved when the refolding was at pH 6.5, 7.5, or 8.5, whereas the foaming capacities could be either slightly increased or decreased when the refolding was at pH 4.5 or 5.5 compared with the controls. The foam stability was in almost all cases improved by the unfolding and refolding treatments except for a few cases of unfolding at pH 1.5 or 10.5. The foam stability and liquid drainage were improved most when the unfolding was at pH 12.5. Analysis of total and surface sulfhydryl groups, surface hydrophobicity, and protein analysis by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) provided strong evidence that the partial unfolding of egg albumen proteins as well as the interactions among egg albumen proteins through disulfide and/or hydrophobic groups dictated the improvements in foaming properties. The increase in surface hydrophobicity showed better correlation with the improvement of foaming properties than the change of surface sulfhydryl content did.
Generation of a low Immunoglobulin E‐binding mutant of the timothy grass pollen major allergen Phl p 5a (2007)

The mutant rPhl p 5a Delta(94-113, 175-198) fulfils the basic requirements for a hypoallergenic molecule suitable for a future immunotherapy of grass pollen allergy; it offers substantially reduced IgE binding and maintained T cell reactivity.
Microring resonators for very large scale integrated photonics (2003)

Microring resonators have three key attributes which make them desirable for Very Large Scale Integrated Photonic Circuits (VLSI-PCs). They provide numerous wavelength selective functions including channel dropping filters, true ON/OFF routing switches, and notch filters, to name a few. The responses of the foregoing devices can always be improved by using multiple rings in coupled cavity arrangements. With reported devices having radii of from 5 /spl mu/m to 25 /spl mu/m, device integration densities of 10/sup 4/ to 10/sup 5/ devices/cm/sup 2/ can be envisioned. In ring resonator based devices, the rings are the wavelength selective elements, while the bus waveguides are simply optical conduits that interconnect rings among themselves or to the outside world. Since rings and bus waveguides serve two different roles, it is desirable to control the parameters of each independently. Vertical coupling allows such flexibility in design. In vertical coupling, air-clad ring resonators are integrated vertically above lower index contrast buried bus waveguides. Vertical integration allows one to optimize the buried waveguides for high input/output fiber coupling efficiency, and for low junction scattering induced cross-talk when bus waveguides cross, while independently optimizing the ring resonator for compactness and low bending loss. It also allows for precision control of the ring-to-waveguide interaction strength.
Extracting atmospheric turbulence and aerosol characteristics from passive imagery (2013)

Obtaining accurate, precise and timely information about the local atmospheric turbulence and extinction conditions and aerosol/particulate content remains a difficult problem with incomplete solutions. It has important applications in areas such as optical and IR free-space communications, imaging systems performance, and the propagation of directed energy. The capability to utilize passive imaging data to extract parameters characterizing atmospheric turbulence and aerosol/particulate conditions would represent a valuable addition to the current piecemeal toolset for atmospheric sensing. Our research investigates an application of fundamental results from optical turbulence theory and aerosol extinction theory combined with recent advances in image-quality-metrics (IQM) and image-quality-assessment (IQA) methods. We have developed an algorithm which extracts important parameters used for characterizing atmospheric turbulence and extinction along the propagation channel, such as the refractive-index structure parameter C<sup>2</sup><sub>n</sub> , the Fried atmospheric coherence width r<sub>0</sub> , and the atmospheric extinction coefficient β<sub>ext</sub> , from passive image data. We will analyze the algorithm performance using simulations based on modeling with turbulence modulation transfer functions. An experimental field campaign was organized and data were collected from passive imaging through turbulence of Siemens star resolution targets over several short littoral paths in Point Loma, San Diego, under conditions various turbulence intensities. We present initial results of the algorithm’s effectiveness using this field data and compare against measurements taken concurrently with other standard atmospheric characterization equipment. We also discuss some of the challenges encountered with the algorithm, tasks currently in progress, and approaches planned for improving the performance in the near future.
A high-speed photocurrent multiplication device based on an organic double-layered structure (2000)

A high-speed photocurrent multiplication device that has an organic double-layered structure was fabricated. In this device, the improvement in the uniformity of the organic films, caused by inserting an additional amorphous-like organic underlayer, enabled high-electric-field operation of the device. Owing to efficient carrier photogeneration under the application of higher voltages, the response time of the multiplied photocurrent became shorter without a decrease in the multiplication rate, and showed clear saturation above 18 V. At a high applied voltage of 20 V, a large multiplication rate of 1.7×105-fold, with a high-speed response of 3.7 s, was achieved. A rise time of only 26 ms required for the 1000-fold multiplication suggests that the multiplication device could potentially be applied to a practical imaging device.
A protein isolated from Brucella abortus is a copper-zinc superoxide dismutase (1990)

Brucella abortus contains a protein that elicits an antigenic response in cattle previously exposed to the organism. The amino acid sequence of the recombinant form of this antigenic protein was determined by gas-phase sequencing of the pyridylethylated protein and its peptides obtained by digestion with cyanogen bromide (CNBr), clostripain, and Staphylococcus aureus V8 protease. The Brucella protein demonstrated 53.6% identity with the Cu-Zn superoxide dismutase (SOD) from Photobacterium leiognathi. Residues essential for metal coordination and enzymatic activity and cysteines required for the formation of the intrasubunit disulfide bridge of Cu-Zn SOD were conserved in the Brucella protein. also exhibited SOD activity that was inhibited by cyanide, which is characteristic of a Cu-Zn SOD. Brucella abortus Cu-Zn SOD is the second prokaryotic Cu-Zn SOD to be sequenced, and the fifth found in prokaryotes. The high degree of conservation between Photobacterium and Brucella Cu-Zn SOD supports the hypothesis of a separately evolved prokaryotic and eukaryotic Cu-Zn SOD gene.
Application of SAFT to Layered, Anisotropic Media (2005)

The synthetic aperture focusing technique (SAFT) is used in ultrasonic inspection to give an enhanced image of defects in parts. Synthetic aperture focusing has been applied to isotropic media for decades. More recently it has been applied to anisotropic media, most prominently unidirectional and homogenized composites. Applying SAFT to anisotropic media is a more complex problem due to directional dependent velocities and beam skew phenomena. This paper presents a SAFT algorithm that treats structures with multiple anisotropic layers as commonly used for composite fabrication. By taking into account the orientation and thickness of each layer, an exact representation of the media is given; therefore better results can be obtained compared to homogenizing the media.
End-to-End Security for DTLS-SRTP (2008)

The end-to-end security properties of DTLS-SRTP depend on the
authenticity of the certificate fingerprint exchanged in the
signalling channel. In current approaches the authenticity is
protected by SIP-Identity or SIP-Identity-Media. These types of
signatures are broken if intermediaries like Session Border
Controllers in other domains change specific information of the SIP
header or the SIP body. The end-to-end security property between the
originating and terminating domain is lost if these intermediaries re-
sign the SIP message and create a new identity signature using their
own domain credentials. This document defines a new signature type
'Fingerprint-Identity' which is exchanged in the signalling
channel. Fingerprint-Identity covers only those elements of a SIP
message necessary to authenticate the certificate fingerprint and to
secure media end-to-end. It is independent from SIP-Identity and SIP-
Identity-Media and can be applied in parallel to them.
A Wideband Index Modulation with Circularly-Shifted Chirps (2021)

In this study, we propose a wideband index modulation (IM) based on circularly -shifted chirps. To derive the proposed method, we first prove that a Golay complementary pair (GCP) can be constructed by linearly combining the Fourier series of chirps. We show that Fresnel integrals and/or Bessel functions, arising from sinusoidal and linear chirps, respectively, can lead to GCPs. We then exploit discrete Fourier transform-spread orthogonal frequency division multiplexing (DFT-s-OFDM) to obtain a low-complexity transmitter and receiver. We also discuss its generalization for achieving a trade-off between peak-to-mean envelope power ratio (PMEPR) and spectral efficiency (SE). Through comprehensive simulations, we compare the proposed scheme with DFT-s-OFDM with IM, orthogonal frequency division multiplexing (OFDM) with IM and complementary sequences (CSs) from Reed-Muller (RM) code. Our numerical results show that the proposed method limits the PMEPR while exploiting the frequency selectivity in fading channels without an auxiliary method.
Proteasome Inhibition by a Totally Synthetic β-Lactam Related to Salinosporamide A and Omuralide (2005)

A new and effective proteasome inhibitor, beta-lactam 3, has been accessed enantioselectively by multistep synthesis from the readily prepared intermediates 7 and 8 which were joined by a [2 + 2]-cycloaddition reaction to form the spiro beta-lactam 9 stereoselectively. The intermediate 9 was converted to 3 in seven steps and 30% overall yield. The beta-lactam 3 is stable for many days in water at pH 7, in contrast to the natural beta-lactones salinosporamide A (1) and omuralide (2). In common with 1 and 2, the beta-lactam 3 effectively inhibits the mammalian proteasome.
Studies on ion scattering and sputtering processes in ion beam sputter-deposition of high Tc superconducting films: The optimization of deposition parameters (1990)

Ion beam sputter‐deposition is one of the techniques used for synthesizing high Tc superconducting films in laboratory experiments. However, the scaling‐up of this method for technological applications, such as in microelectronics, will require a better understanding of basic phenomena occurring during the deposition process. First results are presented here from experimental and computer simulation studies on ion scattering and sputtering processes. It is demonstrated that scattering of neutralized ions from the targets can result in undesirable erosion of, and inert gas incorporation in, the growing films, depending on the ion/target atom mass ratio and ion beam angle of incidence/target/substrate geometry. The studies indicate that sputtering by Kr+ or Xe+ ions is preferable to the most commonly used Ar+ ions, since the undesirable phenomena mentioned above are minimized for the first two ions. These results are used to determine optimum sputter deposition geometry and ions beam parameters for growing high Tc films.
Active optical system for variable view imaging of micro objects with emphasis on kinematic analysis (2008)

Insufficient vision information, such as occlusion, low resolvability, and a small field of view, represent important issues in microassembly and micromanipulation. We propose an active optical system to solve problems related to insufficient vision information through the integration of robotics and optics technologies. The proposed system integrates a double-prism system and a scanning mirror system to supply a compact flexible view. The kinematics of the imaging system is analyzed based on a simplified model initially to investigate the workspace and identify the kinematic performance. A more rigorous analysis of kinematics of the system is then made based on the ray tracing method. The simulation results based on the preliminary design are provided for investigating the workspace and demonstrating the capability of the system in imaging with variable views.
Portable low-coherence interferometer for quantitative phase microscopy of live cells (2013)

We present a compact, highly portable and inexpensive interferometric module for obtaining spatial interferograms of microscopic biological samples, without the strict stability and the highly-coherent illumination that are usually required for interferometric microscopy setups. The module is built using off-the-shelf optical elements and can easily operate with low-coherence illumination, while being positioned in the output of a conventional transmission microscope. The interferograms are processed into the quantitative amplitude and phase profiles of the sample. Based on the phase profile, the optical thickness or optical path delay profile of the sample is obtained with temporal and spatial stabilities, at the order of 0.2-0.3 nm. We show several configurations of this interferometer that are suitable for both on-axis and off-axis holographic geometries, and present various experimental results, including imaging live cells in a non-contact label-free manner and transparent elements with nano-scale thickness. Since the interferometer can be connected to the output of a transmission microscope and operate in a simple way, without involvement of an expert user with a knowledge in optics and without complicated alignment prior to every experiment, and still obtain a remarkably high accuracy, we believe that this new setup will make interferometric phase microscopy more accessible and affordable for biologists and clinicians, while significantly broadening its range of applications.
Direct optical frequency modulation and injection locking of resonant tunnel diode oscillator (1992)

Preliminary results indicate that a resonant tunnel diode (RTD) oscillator can be optically tuned, frequency modulated, and injection locked. Experiments were performed in which a 2.8 GHz RTD oscillator was frequency modulated from DC to 100 MHz and injection locked over a 150 kHz bandwidth with a laser diode via fibre optics.
Compositional effect on the dielectric properties of high-k titanium silicate thin films deposited by means of a cosputtering process (2006)

We report on the successful growth of high dielectric constant (high-k) titanium silicate TixSi1−xO2 thin films of various compositions (0⩽x⩽1) at room temperature from the cosputtering of SiO2 and TiO2 targets. The developed process is shown to offer the latitude required to achieve not only a precise control of the film composition but an excellent morphology (i.e., dense films with low roughness) as well. The Fourier transform infrared and x-ray photoelectron spectroscopy characterizations have evidenced the presence of Ti–O–Si type of atomic environments, which is the fingerprint of the titanium silicate phase. The titanium silicate films are found to exhibit excellent dielectric properties with very low dielectric losses [tan(δ)&lt;0.02] regardless of their composition. The dielectric constant of the films is found to increase with their TiO2 content from 4 (for pure SiO2 films) to 45 (for TiO2). On the other hand, increasing the TiO2 content of the films is also shown to degrade significantly their leakage current. Nevertheless, titanium silicate films with almost equiatomic composition (x∼0.45) are found to exhibit an excellent trade-off between a high-k value (∼18) and low leakage current (∼5×10−7A∕cm2 at 1MV∕cm). Finally, the compositional dependence of the dielectric properties of the TixSi1−xO2 films is discussed in terms of bonding states and optical band gap.
Nanogel-Based PspA Intranasal Vaccine Prevents Invasive Disease and Nasal Colonization by Streptococcus pneumoniae (2013)

To establish a safer and more effective vaccine against pneumococcal respiratory infections, current knowledge regarding the antigens common among pneumococcal strains and improvements to the system for delivering these antigens across the mucosal barrier must be integrated. We developed a pneumococcal vaccine that combines the advantages of pneumococcal surface protein A (PspA) with a nontoxic intranasal vaccine delivery system based on a nanometer-sized hydrogel (nanogel) consisting of a cationic cholesteryl group-bearing pullulan (cCHP). The efficacy of the nanogel-based PspA nasal vaccine (cCHP-PspA) was tested in murine pneumococcal airway infection models. Intranasal vaccination with cCHP-PspA provided protective immunity against lethal challenge with Streptococcus pneumoniae Xen10, reduced colonization and invasion by bacteria in the upper and lower respiratory tracts, and induced systemic and nasal mucosal Th17 responses, high levels of PspA-specific serum immunoglobulin G (IgG), and nasal and bronchial IgA antibody responses. Moreover, there was no sign of PspA delivery by nanogel to either the olfactory bulbs or the central nervous system after intranasal administration. These results demonstrate the effectiveness and safety of the nanogel-based PspA nasal vaccine system as a universal mucosal vaccine against pneumococcal respiratory infection.
DNA and Adenoviral Vectors Encoding Carcinoembryonic Antigen Fused to Immunoenhancing Sequences Augment Antigen-Specific Immune Response and Confer Tumor Protection (2006)

A panel of vectors was constructed to encode carcinoembryonic antigen (CEA) fused at its C-terminal end to various polypeptides, so as to compare their immunogenicity by plasmid DNA immunization and adenovirus injection in wild-type and CEA transgenic (CEA.tg) mice. Fusions between CEA and the minimized domain of tetanus toxin fragment C (CEA-DOM) or the Fc portion of IgG1 (CEA-FcIgG) were identified as highly immunogenic and elicited significant CEA-specific antibody and CD8+ T cell responses. CEA.tg mice were protected from tumor growth on challenge with MC38-CEA tumor cells only when immunized with repeated injections of plasmid pV1J/CEA-DOM followed by Ad/CEA-DOM. Depletion of T-regulatory cells resulted in an increased immune response and antitumor effect with DNA plus adenovirus immunization. In addition, this protective effect was abrogated if the NK, CD4+, or CD8+ cell population from immunized mice was depleted before tumor challenge. Passive transfer studies demonstrated that CD4+ and CD8+ T cells and antibodies contributed to the antitumor effect, thus suggesting that a genetic vaccine based on the use of plasmid DNA and adenoviral vectors encoding CEA fused to immunoenhancing sequences augments CEA-specific immune responses and effectively protects from tumor development.
Recent Advances in the Development of Mammalian Geranylgeranyl Diphosphate Synthase Inhibitors (2017)

The enzyme geranylgeranyl diphosphate synthase (GGDPS) catalyzes the synthesis of the 20-carbon isoprenoid geranylgeranyl diphosphate (GGPP). GGPP is the isoprenoid donor for protein geranylgeranylation reactions catalyzed by the enzymes geranylgeranyl transferase (GGTase) I and II. Inhibitors of GGDPS result in diminution of protein geranylgeranylation through depletion of cellular GGPP levels, and there has been interest in GGDPS inhibitors as potential anti-cancer agents. Here we discuss recent advances in the development of GGDPS inhibitors, including insights gained by structure-function relationships, and review the preclinical data that support the continued development of this novel class of drugs.