gebhart/patrepeval huggingface dataset:
An ultra-wide-field fundus camera with color balanced trans-palpebral illumination (2022)

Many eye diseases, such as diabetic retinopathy (DR) and retinopathy of prematurity (ROP), can cause abnormalities at both central and peripheral regions of the fundus. Therefore, a wide field fundus imaging is desirable for screening, diagnosis, and treatment evaluation of eye diseases. The traditional fundus imaging device which uses trans-pupillary illumination has 30° to 60° field of view. In the trans-pupillary illumination, illumination path and observing path are typically separated by using different portions of the pupil to minimize the effect of reflectance artifact. Therefore, transpupillary illumination limits the field of view because only the central part can be used for imaging purpose. Transpalpebral illumination has been explored as an alternative approach to deliver light to the interior of the eye through the pars-plana, which enables capturing a wide portion of the fundus. Without the need of pharmacologic pupil dilation, a 150° visual angle fundus image was achieved. Previous studies implemented trans-palpebral illumination using a broadband LED. As it is well known that the transmission of long wavelength light is much higher than the short wavelength. Therefore, trans-palpebral illumination based fundus images are red oriented, with compromised image quality for visualizing retinal vasculatures. We have demonstrated the trans-palpebral illumination for the ultra-wide field fundus imaging. We report here the feasibility of using independent green and red illumination power controls to compensate for the difference of spectral efficiency. The color balanced trans-pars-planar illumination significantly increased dynamic range of the fundus camera.
Application of sample stacking to gravity injection in capillary electrophoresis (1991)

Abstract Sample stacking can be used to increase the amount of analyte loaded onto a capillary column without loss in resolution. After the sample is loaded onto the column, the analytes are then separated by conventional capillary zone electrophoresis. When using gravity injection, over an order of magnitude improvement in detection limit is achieved. There is an optimal point for the amount of material which can be injected onto the column based on the resolution desired for the separation.
Cell-Based Indicator to Visualize Picomolar Dynamics of Nitric Oxide Release from Living Cells (2006)

We report a novel cell-based indicator that is able to visualize picomolar dynamics of nitric oxide release from living cells. Cells from a pig kidney-derived cell line (PK15) endogenously express soluble guanylate cyclase (sGC), which is a receptor protein for the selective recognition of NO. Binding of NO by sGC causes the amplified generation of guanosine 3',5'-cyclic monophosphate (cGMP). To make the PK15 cells into NO indicators, the cells are transfected with a plasmid vector encoding a fluorescent indicator for cGMP and fluorescence resonance energy transfer is recorded at 480 +/- 15 and 535 +/- 12.5 nm upon excitation of the cells at 440 +/- 10 nm. The cell-based indicator exhibits exceptional sensitivity (detection limit of 20 pM), selectivity, reversibility, and reproducibility. The outstanding sensitivity of the present indicator has led us to uncover an oscillatory release of picomolar concentrations of NO from hippocampal neurons. We present evidence that Ca2+ oscillations in hippocampal neurons underlie the oscillatory NO release from the neurons during neurotransmission. We also have succeeded in visualizing the extent of diffusing NO from single vascular endothelial cells. The present cell-based indicator provides a powerful tool to uncover picomolar dynamics of NO that regulates a wide range of cell functions in biological systems.
Hydroxymethylated Resorcinol Coupling Agent for Enhanced Durability of Bisphenol-A Epoxy Bonds to Sitka Spruce (1995)

Epoxy adhesives can develop bonds to wood that are as strong as the wood itself, but only if the\nbonds remain dry. Once exposed to repeated water soaking and severe stresses from drying, epoxy\nbonds delaminate and fail to meet requirements for structural wood adhesives intended for exterior\nexposure. A new hydroxymethylated resorcinol (HMR) coupling agent, applied to lumber surfaces\nbefore bonding, chemically couples both epoxy adhesive and lignocellulosics of wood to produce bonds\nto Sitka spruce that are extraordinarily resistant to delamination. In this report, we explain and\ndemonstrate the nature of this coupling agent and the mechanism by which it enhances the durability\nof bonds of a bisphenol-A epoxy adhesive to wood. When diluted with benzyl alcohol, an epoxy\nadhesive developed structural bonds in HMR-primed lumber laminates that met the 5% maximum\ndelamination requirement of ASTM Specification D 2559. The USDA Forest Service has applied for\na patent for this invention.
Improved Equalization For Coded, Zero-Padded OFDM (ZP-OFDM) Systems (2007)

Zero-padded OFDM (ZP-OFDM) systems have recently been adopted in certain wireless systems, such as the multiband-OFDM based WiMedia standard, instead of the more commonly used cyclic-prefix OFDM (CP-OFDM). ZP-OFDM offers potentially superior performance in multipath channels only if more complex equalization, such as minimum-mean- squared-error (MMSE) or least-squares (LS) is performed at the receiver instead of the more commonly used overlap-add (OLA) equalizer. These complex schemes usually involve inversion of a non-diagonal, channel-dependent matrix that cannot be precomputed. In this paper we first develop two simplified algorithms for equalization of uncoded OFDM signals that improve performance in channels with spectral nulls compared to the OLA equalizer. We then develop a novel, iterative metric-calculation method for coded OFDM that with proper initialization requires only two iterations to approach the performance of a LS equalizer, without the need for matrix inversions. Simulation results will be presented to demonstrate the performance of the proposed algorithms.
Microphotonic thermal detectors and imagers (2009)

We present the theory of operation along with detailed device designs and initial experimental results of a new class of uncooled thermal detectors. The detectors, termed microphotonic thermal detectors, are based on the thermo-optic effect in high quality factor (Q) micrometer-scale optical resonators. Microphotonic thermal detectors do not suffer from Johnson noise, do not require metallic connections to the sensing element, do not suffer from charge trapping effects, and have responsivities orders of magnitude larger than microbolometer-based thermal detectors. For these reasons, microphotonic thermal detectors have the potential to reach thermal phonon noise limited performance.
Genetic suppression analysis of non-antibiotic-producing mutants of the Streptomyces coelicolor absA locus (1999)

The absA locus in Streptomyces coelicolor A3(2) was identified because mutations in it uncoupled sporulation from antibiotic synthesis: absA mutants failed to produce any of the four antibiotics characteristic of S. coelicolor. These mutants are now shown to contain point mutations in the absA1 gene which encodes the histidine kinase sensor-transmitter protein of a two-component signalling system. The absA1 non-antibiotic-producing mutants, which are unpigmented, spontaneously acquire pigmented colony sectors. Genetic analysis established that the pigmented sectors contain second-site suppressive mutations, sab (for suppressor of abs). Phenotypic characterization showed that sab strains produce all four antibiotics; some overproduce antibiotics and are designated Pha, for precocious hyperproduction of antibiotics. A set of sab mutations responsible for suppression was localized by plasmid-mediated and protoplast fusion mapping techniques to the vicinity of the absA locus. DNA cloned from this region was used to construct phage that could transduce sab mutations. Sequence analysis of sab strains defined sab mutations in both the absA1 gene and the absA2 gene; the latter encodes the two-component system's response regulator.
cdtB gene-based multiplex PCR for detection of Campylobacter spp. isolated from rectal swab culture of diarrheal children in Bamrasnaradura Infectious Diseases Institute (2012)

Multiplex PCR technique was used for detecting the cdtB gene of Campylobacter  spp. isolated from rectal swabs of diarrheal children at Bamrasnaradura Infectious  Diseases Institute. Of the 691 samples analyzed by the multiplex PCR, 28 (4.1 %) were positive for Campylobacter spp.; 24 samples (3.5 %) for Campylobacter jejuni and 4 samples (0.6 %) for Campylobacter coli . The conventional culture method could detect 15 isolates (2.2 %) of C. jejuni   and 1 isolate (0.1 %) of  C. coli  from all rectal swab samples. These data showed that the cdtB gene-based multiplex PCR technique provided better result for detection and identification of Campylobacte r spp. than that of the conventional culture method.
An endogenous dinucleotide bound to diphtheria toxin. Adenylyl-(3',5')-uridine 3'-monophosphate. (1981)

Diphtheria toxin has recently been fractionated into two forms, one of which contains tightly but noncovalently bound nucleotide-like material. Here we report identification of the major nucleotide constituent (comprising 80% of the total extractable ultraviolet-absorbing material) as adenylyl-(3',5')-uridine 3'-monophosphate (ApUp). Upon incubation with ApUp, the nucleotide-free form of toxin bound approximately one molar equivalent of the dinucleotide and was converted to a form similar or identical with the native nucleotide-bound form.
Functional Anatomy of the Trimer Apex Reveals Key Hydrophobic Constraints That Maintain the HIV-1 Envelope Spike in a Closed State (2021)

The human immunodeficiency virus type 1 (HIV-1) envelope trimer maintains a closed, metastable configuration to protect vulnerable epitopes from neutralizing antibodies. Here, we identify key hydrophobic constraints at the trimer apex that function as global stabilizers of the HIV-1 envelope spike configuration. Mutation of individual residues within four hydrophobic clusters that fasten together the V1V2, V3, and C4 domains at the apex of gp120 dramatically increases HIV-1 sensitivity to weak and restricted neutralizing antibodies targeting epitopes that are largely concealed in the prefusion Env spike, consistent with the adoption of a partially open trimer configuration. Conversely, the same mutations decrease the sensitivity to broad and potent neutralizing antibodies that preferentially recognize the closed trimer. Sera from chronically HIV-infected patients neutralize open mutants with enhanced potency, compared to the wild-type virus, suggesting that a large fraction of host-generated antibodies target concealed epitopes. The identification of structural constraints that maintain the HIV-1 envelope in an antibody-protected state may inform the design of a protective vaccine.<b>IMPORTANCE</b> Elucidating the structure and function of the HIV-1 envelope proteins is critical for the design of an effective vaccine. Despite the availability of many high-resolution structures, key functional correlates in the envelope trimer remain undefined. We utilized a combination of structural analysis, <i>in silico</i> energy calculation, mutagenesis, and neutralization profiling to dissect the functional anatomy of the trimer apex, which acts as a global regulator of the HIV-1 spike conformation. We identify four hydrophobic clusters that stabilize the spike in a tightly closed configuration and, thereby, play a critical role in protecting it from the reach of neutralizing antibodies.
Study on New Developed CVT Having Third Pulley, Tensioner Using Dry Hybrid V-Belts - How Does It Transmit Power at Both Steady and Transitional States? (2004)

<div class="htmlview paragraph">A new three-pulley CVT (Continuously Variable Transmission) with a tensioner has been developed using dry hybrid V-belts. It can transmit higher torque than conventional two-pulley CVT without a tensioner, because the tensioner increases not only a lap angle where power is transmitting but also it can always keep the belt tension optimum. This study shows whether the Euler's power transmitting theory is applicable to the tensioner type CVT to characterize the CVT operation for preliminary design. The tensioner type CVT has also high shifting speed and it does not need large thrusts on both driving and driven pulleys during shifting since the minimum tension for torque transfer is assured in the slack-side string. The FEM analysis revealed the shifting mechanism and showed that the transmitting force distribution in the pulley groove for the newly developed CVT is almost the same as that for the conventional CVT.</div>
OSPF Out-of-Band Link State Database (LSDB) Resynchronization (2007)

OSPF is a link-state intra-domain routing protocol used in IP
networks. Link State Database (LSDB) synchronization in OSPF is
achieved via two methods -- initial LSDB synchronization when an OSPF
router has just been connected to the network and asynchronous
flooding that ensures continuous LSDB synchronization in the presence
of topology changes after the initial procedure was completed. It may
sometime be necessary for OSPF routers to resynchronize their LSDBs.
The OSPF standard, however, does not allow routers to do so without
actually changing the topology view of the network. This memo
describes a vendor-specific mechanism to perform such a form of out-
of-band LSDB synchronization. The mechanism described in this document
was proposed before Graceful OSPF Restart, as described in RFC 3623,
came into existence. It is implemented/supported by at least one major
vendor and is currently deployed in the field. The purpose of this
document is to capture the details of this mechanism for public use.
This mechanism is not an IETF standard. This memo provides information
for the Internet community.
Interferon inducing activities of derivatives of 1,3-dimethyl-4-(3-dimethylaminopropylamino)-1H-pyrazolo[3,4-b]quinoline and related compounds (1976)

Syntheses and interferon inducing acitivites are reported for 137 relatives of 1,3-dimethyl-4-(3-dimethylamino-propylamino)-1H-pyrazolo[3,4-b]quinoline (1). Three different generalized synthetic schemes for the preparation of pyrazolo[3,4-b]quinolines are presented and limitations contrasted. Other heterocyclic nuclei containing the 3-dimethylaminopropylamino side chain include pyridine, quinoline, acridine, pyrazolo[3,4-b]pyridine, pyrazolo[3,4-B][1,8]naphthyridine, pyrazolo[4',3':5,6]pyrido[2,3-d]pyrimidine, dipyrazolo[3,4-b:4',3'-e]pyridine, pyrrolo-[2,3-b]quinoline, isothiazolo[5,4-b]quinoline, and pyrido[2,3-h]pyrazolo[3,4-b]quinoline. Structural requirements for interferon induction in this series are discussed and two of the more active compounds (172 and 196) are compared directly with tilorone.
Diode-based CMOS MEMS thermal flow sensors (2017)

This paper reports on the intrinsic advantages of thermoelectronic flow sensors in comparison to their thermoresistive and thermoelectric counterparts. Hereafter, we will numerically and experimentally show that thermoelectronic flow sensors (i.e. thermal flow sensors employing p-n junction based devices as temperature sensors) benefit from the possibility of having the temperature sensor located in the hottest area of the heating element for enhanced convective effects and thus improved sensor sensitivity (Average Sensitivity +42%). Further improvements can be achieved by putting more diodes in series (Average Sensitivity +380%). A multidirectional thermoelectronic flow sensor is also reported.
Concurrent Search of Mobile Users in Cellular Networks (2004)

In this paper, we propose to concurrently search for a number of mobile users in a wireless cellular network based on the probabilistic information about the locations of mobile users. The concurrent search approach guarantees that all k mobile users will be located within k time slots. It is shown that even in the worst case when mobile users appear equally in all the cells of the network, the concurrent search approach is able to reduce the average paging cost by 25%. More importantly, this is achieved without an increase in the worst case paging delay or in the worst case paging cost. Depending on the total number of mobile users to be located, total number of cells in the network, and the probabilistic information about the locations of mobile users, the reduction of the average paging cost due to the usage of the concurrent search approach ranges from 25% to 88%. The case in which perfect probabilistic information is unavailable is also studied.
Exploration of Microwave Plasma Source Cavity Ring-Down Spectroscopy for Elemental Measurements (2003)

We are exploring sensitive techniques for elemental measurements using cavity ring-down spectroscopy (CRDS) combined with a compact microwave plasma source as an atomic absorption cell. The research work marries the high sensitivity of CRDS with a low-power microwave plasma source to develop a new instrument that yields high sensitivity and capability for elemental measurements. CRDS can provide orders of magnitude improvement in sensitivity over conventional absorption techniques. Additional benefit is gained from a compact microwave plasma source that possesses the advantages of low power and low-plasma gas flow rate, which are of benefit for atomic absorption measurements. A laboratory CRDS system consisting of a tunable dye laser is used in this work for developing a scientific base and demonstrating the feasibility of the technique. A laboratory-designed and -built sampling system for solution sample introduction is used for testing. The ring-down signals are monitored using a photomultiplier tube and recorded using a digital oscilloscope interfaced to a computer. Lead is chosen as a typical element for the system optimization and characterization. The effects of baseline noise from the plasma source are reported. A detection limit of 0.8 ppb (10(-)(10)) is obtained with such a device.
Silhouette-Based Gender Recognition in Smart Environments Using Fuzzy Local Binary Patterns and Support Vector Machines (2017)

Automatic recognition of human gender in smart environments is an interesting problem in biometric and demographic studies. In this paper, we describe a method for gender recognition at a distance based on visual texture analysis of gait energy images (GEIs). These images summarize the structural and dynamical variations of the subject's silhouette during one gait cycle. Texture analysis and feature extraction are based on histogram calculation of fuzzy local binary pattern (FLBP), which describes the relative intensities of each pixel with surrounding neighbors. Unlike the original LBP, each pixel can contribute, with different weights, to more than one bin in the histogram of occurring codes. The classification model uses support vector machines with linear kernel function. The performance of the proposed approach is intensively evaluated and compared with other texture on CASIA B multiview gait database. We also consider the variation of some conditions such as clothing and carried objects. Results show that the proposed approach is promising and outperforms other variants in representing texture for gait-based gender recognition.
A single camera based rear obstacle detection system (2011)

This paper presents a rear obstacle detection system by using a single rear view camera. The system can detect various static and moving obstacles behind the cars. An efficient hierarchical detecting strategy is used to achieve high detection rate and low false positives. The temporal Inverse perspective mapping difference image based coarse detection is used to estimate whether there are obstacles in the predetermined warning area at first stage. Then a novel integral image based segmentation algorithm is developed for fine obstacle segmentation. Finally, the blob analysis is utilized for obstacle representation and verification. Our system achieves 94.2% detection rate and 16% false positives rate on 125 challenging video sequences. The average processing speed of the system is 25fps on a standard laptop.
SIMULTANEOUS MEASUREMENTS OF STRESS AND DISTORTION OF THE CERAMIC-METAL JOINTS BY SCANNING ACOUSTIC MICROSCOPY (1992)

Abstract Simultaneous measurements of stress and distortion of ceramic-metal joints were investigated using the scanning acoustic microscopy. The principle of the methodology is the measurement of the X-Z image, which is obtained by the synchronized movement of an acoustic lens in both the X- and Z-directions. This paper details the measurment and analytical procedures and provides results for silicon nitride ceramic-nickel joints, which were subjected to thermal cycles between room temperature and 1073K.
Detection of hydatidiform mole in maternal serum screening programmes for Down's syndrome (1992)

Many molar pregnancies that have not presented clinically before 15 weeks will be detected through Down's syndrome screening.
A Novel Modified Switched Inductor Boost Converter with Reduced Switch Voltage Stress (2020)

DC-DC power converters are necessary to step-up the voltage or current with high conversion ratio for many applications e.g. photovoltaic and fuel cell energy conversion, uninterruptible power supply, DC microgrid, automobile, high intensity discharged lamp ballast, hybrid vehicle, etc. in order to use low voltage sources. In this project, a modified SIBC (mSIBC) is proposed with reduced voltage stress across active switches. The proposed mSIBC configuration is transformerless and simply derived by replacing one diode of the classical switched inductor structure with an active switch. As a result, mSIBC required low voltage rating active switches, as the total output voltage is shared between two active switches. Moreover, the proposed mSIBC is low in cost, provides higher efficiency and required the same number of components compared to the classical SIBC. The experimental results are presented which validated the theoretical analysis and functionality, and the efficiency of the designed converter is 97.17%. The proposed mSIBC converter provides higher voltage conversion ratio compared to classical converters e.g. boost, buck-boost, cuk, and SEPIC. The newly designed configurations will aid the intermediate power stage between the renewable sources and utility grid or high voltage DC or AC load. Since, the total output voltage is distributed among the two active switches, low voltage rating switches can be employed to design the power circuit of the proposed converter. The classical boost converter or recently proposed switched inductor based boost converter can be replaced by the proposed mSIBC converter in real-time applications such as DC microgrid, DC-DC charger, battery backup system, UPS, EV, an electric utility grid. The proposed power circuitry is cost effective, compact in size, easily diagnostic, highly efficient and reliable.
Dopamine production in Enterococcus faecium: A microbial endocrinology-based mechanism for the selection of probiotics based on neurochemical-producing potential (2018)

The mechanisms by which probiotics may influence host physiology are still incompletely understood. Microbial endocrinology, a field representing the union of microbiology, endocrinology and neurobiology, has theorized that microorganisms have the capacity to serve as neurochemical delivery vehicles [1]. According to microbial endocrinology, neurochemicals can serve as a common language between host and bacterium, enabling bidirectional communication. We report herein the first demonstration that Enterococcus sp. has the capacity to produce dopamine in a gastrointestinal-like environment when supplied with the dopamine precursor L-3,4 dihydroxyphenylalanine (L-dopa). The results presented herein provide a means to select probiotics based on neurochemical-producing potential and suggest the possibility that probiotics containing E. faecium may serve to influence the host through dopaminergic pathways.