gebhart/patrepeval huggingface dataset:
DNQ–novolac photoresists revisited: 1H and 13C NMR evidence for a novel photoreaction mechanism (2003)

Abstract Photoactive compounds, such as diazonaphthoquinone (DNQ) esters, blended with novolac resins, solvents and certain additives, serve as photoresists. These are used for printing of electronic circuits at the micron or sub‐micron level. Patterns are generated based on changes in the physical and chemical properties of the exposed and unexposed photoresist surfaces (printed circuit boards). The huge polarity change between the exposed and unexposed photoresists is exploited in the technique of microlithography. It is believed that the large polarity difference is due to acid formation in the exposed photoresist by a photochemical reaction of DNQ on exposure to light. However, it has also been suggested that in the unexposed part of a photoresist, the novolac resin undergoes an azo coupling reaction with DNQ, leading to an increase in the molecular weight of the resin, rendering it more insoluble in base. The protons in the para positions of the m ‐cresol units incorporated in the novolac resin are believed to take part in this azo coupling reaction with DNQ. In this paper, we propose a novel mechanism of action of positive photoresists in the unexposed part of photoresists for dissolution inhibition using molecular modelling, 1 H NMR, 13 C NMR and DEPT‐135 NMR spectroscopic techniques. Our results enable us to propose that the diazo group of DNQ attacks the methylene bridges rather than the aromatic moiety of the resin. This mechanism explains the pattern formation observed using even p ‐cresol‐based resins, where no free para positions are present in the aromatic ring. Copyright © 2003 John Wiley &amp; Sons, Ltd.
The 9-phenylxanthen-9-yl protecting group (1978)

9-Chloro-9-phenylxanthene (4b) reacts with the 5′-hydroxy groups of 2′-deoxyribonucleosides (2)(and their N-acyl derivatives) to give crystalline 9-phenylxanthen-9-yl (pixyl) derivatives (5) in satisfactory to good yields; the pixyl group may be removed by acidic hydrolysis under very mild conditions.
Death Receptor 5 Regulation during Selenium-Mediated Apoptosis in Human (2002)

Selenium is an essential micronutrient that is currently being tested for prostate cancer chemoprevention. In spite of its significant promise as a chemopreventive agent, the molecular mechanisms of selenium-mediated effects remain to be elucidated. Recent evidence suggests that selenium may mediate its chemopreventive effects by inducing apoptosis in human prostate cancer cells. Here we report that selenium-mediated apoptosis appears to involve membrane death receptor, DR5-dependent pathway in human prostate cancer cells. Selenium specifically upregulated DR5 expression but not that of DR4. Selenium upregulation of DR5 was coupled with caspase 8 activation and Bid cleavage thereby suggesting the existence of a potential cross-talk between the DR5 and the mitochondrial pathways. Thus, our results suggest that DR5 is specifically regulated by selenium and its activation may play an important role in selenium-mediated chemoprevention.
Deep Learning on Real Geophysical Data: A Case Study for Distributed Acoustic Sensing Research (2020)

Deep Learning approaches for real, large, and complex scientific data sets can be very challenging to design. In this work, we present a complete search for a finely-tuned and efficiently scaled deep learning classifier to identify usable energy from seismic data acquired using Distributed Acoustic Sensing (DAS). While using only a subset of labeled images during training, we were able to identify suitable models that can be accurately generalized to unknown signal patterns. We show that by using 16 times more GPUs, we can increase the training speed by more than two orders of magnitude on a 50,000-image data set.
Assay of retinoids in biological samples by reverse-phase high-pressure liquid chromatography. (1978)

A separation procedure for retinoids based on reversephase high-pressure liquid chromatography with solvent mixtures of acetonitrile and water is described. The method may be applied to the screening of synthetic retinoids, which have potential for use in the prevention of cancer. It is easily adapted to a variety of biological samples and can be applied to other conventional retinoid assays in liver and plasma, detecting as little as 1 nmol retinyl esters and less than 0.3 nmol retinol per g tissue. The one-step chromatography results in separation and simultaneous determination of many of the synthetic retinoids and all of the natural retinoids, including the retinyl esters that are separated into their major fatty acid components. The method has been applied to the analysis of retinoid levels in the liver and intestine of vitamin A-deficient hamsters following a p.o. dose (0.5 mg/day for 2 days) of retinyl acetate or of a synthetic vitamin A analog and is predictive of the degree to which various synthetic retinoids can be converted to retinol and stored in the liver as retinyl esters. Because of its speed, excellent recoveries, and high resolution, the method offers significant advantages over previous, more lengthy procedures.
Theory of photo-capacitance in amorphous silicon MIS structures (1982)

Abstract A theoretical treatment is presented in which the small-signal, space-charge capacitance, C sc, in a-Si MIS structures is calculated for varying levels of illumination. Bulk recombination and a sufficient density of states at the insulator-semiconductor interface to pin the Fermi level and produce a significant surface band-bending are assumed. It is shown that the trapping state density as a function of energy in the mobility gap can be derived from measurement of C sc at different levels of illumination. The method is particularly applicable in cases where the surface-state density is large enough to preclude field-effect measurements.
Exact Analysis of Intrinsic Qualitative Features of Phosphorelays using Mathematical Models (2011)

Phosphorelays are a class of signaling mechanisms used by cells to respond to changes in their environment. Phosphorelays (of which two-component systems constitute a special case) are particularly abundant in prokaryotes and have been shown to be involved in many fundamental processes such as stress response, osmotic regulation, virulence, and chemotaxis. We develop a general model of phosphorelays extending existing models of phosphorelays and two-component systems. We analyze the model analytically under the assumption of mass-action kinetics and prove that a phosphorelay has a unique stable steady-state. Furthermore, we derive explicit functions relating stimulus to the response in any layer of a phosphorelay and show that a limited degree of ultrasensitivity (the ability to respond to changes in stimulus in a switch-like manner) in the bottom layer of a phosphorelay is an intrinsic feature which does not depend on any reaction rates or substrate amounts. On the other hand, we show how adjusting reaction rates and substrate amounts may lead to higher degrees of ultrasensitivity in intermediate layers. The explicit formulas also enable us to prove how the response changes with alterations in stimulus, kinetic parameters, and substrate amounts. Aside from providing biological insight, the formulas may also be used to avoid time-consuming simulations in numerical analyses and simulations.
Trauma to the High Cervical Carotid Artery (1984)

An alternative approach to the treatment of distal extracranial nonoccluding internal carotid artery penetrating injuries is described in which internal carotid artery ligation is followed expectantly. A warning transient neurologic deficit prompted an unsuccessful attempt at revascularization via a superficial temporal artery to middle cerebral artery anastomosis. The failure of the anastomosis was thought to be secondary to a postinjury hypercoagulable state and a diminished demand for intracranial blood flow secondary to an unexpected, impressive development of collateral blood supply.
Restricted Arp3 expression in the testis prevents blood–testis barrier disruption during junction restructuring at spermatogenesis (2010)

In epithelia, a primary damage of tight junctions (TJ) always leads to a secondary disruption of adherens junction (AJ), and vice versa. This response, if occurring in the testis, would disrupt spermatogenesis because the blood-testis barrier (BTB) must remain intact during the transit of spermatids in the seminiferous epithelium, which is associated with extensive apical ectoplasmic specialization (apical ES, a testis-specific AJ type) restructuring. As such, apical ES restructuring accompanied with the transit of developing spermatids during spermiogenesis must be segregated from the BTB to avoid an immunological barrier breakdown in all stages of the seminiferous epithelial cycle, except at stage VIII when spermiation and BTB restructuring take place concurrently. We report herein a mechanism involving restricted spatial and temporal expression of Arp2/3 complex and N-WASP, whose actin branching activity associated with apical ES and BTB restructuring in the seminiferous epithelium. High expression of Arp3 at the apical ES was shown to correlate with spermatid movement and proper spermatid orientation. Likewise, high Arp3 level at the BTB associated with its restructuring to accommodate the transit of preleptotene spermatocytes at stage VIII of the epithelial cycle. These findings were validated by in vitro and in vivo studies using wiskostatin, an inhibitor that blocks N-WASP from activating Arp2/3 complex to elicit actin branching. Inhibition of actin branching caused a failure of spermatid transit plus a loss of proper orientation in the epithelium, and a "tightened" Sertoli cell TJ permeability barrier, supporting the role of Arp2/3 complex in segregating the events of AJ and BTB restructuring.
Medical Student and Resident Dermatology Education in Canada During the COVID-19 Pandemic (2021)

The coronavirus disease 2019 (COVID-19) pandemic and subsequent physical distancing recommendations created major gaps in traditional dermatologic undergraduate and postgraduate medical education delivery. Nevertheless, the educational consequences of various public health restrictions have indirectly set aside the inertia, resistance, and risk averse approach to pedagogical change in medicine. In Canada, rapid collaboration and innovation in dermatologic education has led to novel programs including the implementation of a range of internet-facilitated group learning activities and a dramatic expansion of digital telehealth and virtual care. Going forward, three key issues arising from these developments will need to be addressed: the ongoing assessment of these innovations for efficacy; sustaining the momentum and creativity that has been achieved; and, determining which of these activities are worth maintaining when traditional "tried and true" learning activities can be resumed.
Mechanical to electrical energy conversion in a hybrid liquid-solid dielectric electrostatic generator (2009)

The authors are studying the effect of the dielectric choice in electrostatic generators on the energy yield. Despite having high permittivities, solid dielectrics are shown to have a lower performance than is first apparent, due to the effect of the air gap. Liquid dielectrics are found to offer higher overall equivalent permittivities compared to solid dielectrics with air gaps but the conductivity of liquids limits their performance. Experimental work has been conducted using a hybrid generator which incorporates both solid and liquid layers. The solid polyvinylidene fluoride layer is used to limit the conduction between the plates and the liquid dielectric is withdrawn or injected for the necessary change in capacitance. The experimental work has demonstrated a number of design considerations for such generators and is ultimately used to show that energy conversion is possible using this electrostatic generator configuration.
High Altitude Long Endurance Air Vehicle Analysis of Alternatives and Technology Requirements Development (2007)

The objective of this study was to develop a variety of High Altitude Long Endurance (HALE) Unmanned Aerial Vehicle (UAV) conceptual designs for two operationally useful missions (hurricane science and communications relay) and compare their performance and cost characteristics. Sixteen potential HALE UAV configurations were initially developed, including heavier-than-air (HTA) and lighter-than-air (LTA) concepts with both consumable fuel and solar regenerative (SR) propulsion systems. Through an Analysis of Alternatives (AoA) down select process, the two leading consumable fuel configurations (one each from the HTA and LTA alternatives) and an HTA SR configuration were selected for further analysis. Cost effectiveness analysis of the consumable fuel configurations revealed that simply maximizing vehicle endurance can lead to a sub-optimum system solution. An LTA concept with a hybrid propulsion system (solar arrays and a hydrogen-air proton exchange membrane fuel cell) was found to have the best mission performance; however, an HTA diesel-fueled wing-body-tail configuration emerged as the preferred consumable fuel concept because of the large size and technical risk of the LTA concept. The baseline missions could not be performed by even the best HTA SR concept. Mission and SR technology trade studies were conducted to enhance understanding of the potential capabilities of such a vehicle. With near-term technology SR-powered HTA vehicles are limited to operation in favorable solar conditions, such as the long days and short nights of summer at higher latitudes. Energy storage system specific energy and solar cell efficiency were found to be the key technology areas for enhancing HTA SR performance.
The Behavior of Water in Jet Fuels and the Clogging of Micronic Filters at Low Temperatures (1950)

A study of the behavior of water in fuels, and its effect on the clogging of micronic type filters, especially at low temperatures has been made. A method for the determination of water in fuels using the Karl Fischer reagent has been developed and used in the determination of the solubility of water in several fuels and pure hydrocarbons from 32 deg F to 120 deg F. The effect of aromatic content, rates of saturation and disappearance of suspended water from fuels have been investigated. A small scale apparatus was devised for the study of the clogging of micronic filters at low temperatures. The variables - temperature, water content of the fuel, fuel pressure, porosity and type of paper were studied for their effects on filter clogging. Mechanisms of clogging as a function of temperature are proposed. A number of representative substances were tested as potential freezing point depressants for the prevention of clogging. In general, it was found that the more hydrophylic compounds are the more effective antifreezes. However, these compounds are the ones more readily leached from the fuel by contact with water. Methyl alcohol was found to have the best antifreeze action, but it is lost very readily from fuel solutions to water. In selecting a suitable antifreeze, due consideration must be given to the methods of handling the fuel and to the methods which may be used for the introduction of the additive.
Methods for distinguishing type of hypersonic boundary layer in shock tunnel (1968)

Abstract : An experimental program for studying the transition phenomenon, boundary layer characteristics, and local heat transfer rates on 4- and 8-foot long 10 deg included angle cones in a hypersonic chock tunnel has brought about the development and improvement of instrumentation and methods for distinguishing hypersonic laminar, transition, and turbulent boundary layers in relatively short test time experimental facilities. The methods used include schlieren optics, local heat transfer rates from thin-film sputtered platinum surface gauges, and surveys through the boundary layer using impact pressure, total temperature, and thin heat transfer wedges. Also, the actual oscilloscope traces, directly from the heat transfer instrumentation, be used to define the type of boundary layer. (Author)
Backscattering effects in the elastic scattering of p-polarized light from a large-amplitude random metallic grating (1989)

We study the scattering of a p-polarized beam incident onto a random grating whose grooves are perpendicular to the plane of incidence. The scattered field is expressed in terms of the total magnetic field and its normal derivative on the surface of the grating. The integral equations satisfied by these functions are solved numerically for each of several hundred realizations of the surface profile possessing a Gaussian spectrum. The diffuse component of the differential reflection coefficient averaged over these realizations displays a well-defined peak in the retroreflection direction for metallic and perfectly conducting random gratings but not for random gratings on dielectric surfaces.
Alpha-1 antitrypsin up-regulates human B cell differentiation selectively into IgE- and IgG4-secreting cells (1998)

Numerous allergens have proteolytic activities. It has been speculated that this property may contribute to their allergenicity. Therefore, we have evaluated the effect of different physiological protease inhibitors (PI) on the regulation of human IgE synthesis. Unexpectedly, the serine PI, alpha-1 antitrypsin, also called alpha-1 protease inhibitor (alpha1PI), induced a potent and selective dose-dependent increase of IgE and IgG4 production by human tonsillar B cells stimulated with the IgE and IgG4 switch factors, IL-4 and anti-CD40 mAb. The other serine PI tested were inefficient. Furthermore, this effect of alpha1PI was accompanied by an increase in (1) germ-line and mature sigma mRNA transcription, (2) proliferation and (3) membrane CD23 and CD21 expression, while the expression of other molecules involved in the regulation of IgE synthesis was unchanged. Since CD23-CD21 pairing plays a crucial role in the up-regulation of IgE synthesis, we have tested whether blocking this interaction affected alpha1PI-increased IgE production. The neutralizing anti-CD23 mAb, Mab 25, partly reversed the IgE increase caused by alpha1PI. Moreover, alpha1PI potentiation of IgE synthesis was prevented by elastase, a natural substrate of alpha1PI, thereby suggesting that alpha1PI may inhibit endogenous B cell enzyme(s) involved in the down-regulation of IgE synthesis. Alpha1PI also potentiated IgE and IgG4 production by IL-4-stimulated peripheral blood mononuclear cells but was not a switch factor for IgE and IgG4 as it was unable to replace IL-4 or anti-CD40 mAb in inducing IgE and IgG4 production. In conclusion, this study shows that alpha1PI acts as a potent co-stimulus for IgE and IgG4 synthesis and suggests that the equilibrium between protease/ protease inhibitor participates in the control of human IgE and IgG4 synthesis.
Early DSE and Automatic Generation of Coarse Grained Merged Accelerators (2021)

Post-Moore's law area-constrained systems rely on accelerators to deliver performance enhancements. Coarse grained accelerators can offer substantial domain acceleration, but manual, ad-hoc identification of code to accelerate is prohibitively expensive. Because cycle-accurate simulators and high-level synthesis flows are so time-consuming, manual creation of high-utilization accelerators that exploit control and data flow patterns at optimal granularities is rarely successful. To address these challenges, we present AccelMerger, the first automated methodology to create coarse grained, control- and data-flow-rich, merged accelerators. AccelMerger uses sequence alignment matching to recognize similar function call-graphs and loops, and neural networks to quickly evaluate their post-HLS characteristics. It accurately identifies which functions to accelerate, and it merges accelerators to respect an area budget and to accommodate system communication characteristics like latency and bandwidth. Merging two accelerators can save as much as 99% of the area of one. The space saved is used by a globally optimal integer linear program to allocate more accelerators for increased performance. We demonstate AccelMerger's effectiveness using HLS flows without any manual effort to fine-tune the resulting designs. On FPGA-based systems, AccelMerger yields application performance improvements of up to 16.7x over software implementations, and 1.91x on average with respect to state-of-the-art early-stage design space exploration tools.
Progress of broadband wave-transparent radome (2011)

Radome is becoming the bottleneck technique of anti-radiation missile as for the higher demand for high performance of broadband wave-transparency and high temperature resistance. Based on the fundamental theory of broadband wave-transparent radome, the review focuses on the structure design and processing at home and abroad. Furthermore, the problems which may exist in the design, preparation and machining of broadband wave-transparent radome are outlined.
Complex triarylsulfonium salt photoinitiators. I. The identification, characterization, and syntheses of a new class of triarylsulfonium salt photoinitiators (1980)

Abstract Dilphenyl‐4‐thiophenoxyphenylsulfonium salts have been found to be more efficient cationic photoinitiators than the highly photoactive triphenylsulfonium salts. The former compounds were identified as by‐products produced in the preparation of triphenylsulfonium chloride from benzene, chlorine, sulfur monochloride, and aluminum chloride. Confirmation of the structure was made by NMR and UV spectroscopy as well as by independent synthesis. The photoinitiated cationic polymerization of cyclohexene oxide and other epoxy monomers was carried out to demonstrate the higher efficiency of diphenyl‐4‐thiophenoxysulfonium hexafluoroarsenate as compared to the corresponding triphenylsulfonium salt.
Detection and prediction of lung tumor motion with fluoroscopy (2002)

A new radiotherapy adjunct system capable of tracking tumor motion due to breathing has been proposed. The properties of tumor motion with breathing were determined from fluoroscopic video recorded during patient simulation. Real-time patient motion during treatment was detected with noninvasive motion sensing and the immediate-future tumor position was predicted in correlation with the pre-determined motion properties to guide the treatment field. Here, the authors report their solutions to some critical problems with this system. The pincushion distortion of the fluoroscopic imaging system was corrected with a 5/sup th/ order two-dimensional polynomial unwarping function based on the measurement with a fine lead-grid phantom. Temporal Fourier transformation of the fluoroscopic video provided a static view of the motion field. Regions with different motion ranges can be quickly measured. In order to obtain real time tumor position with noninvasive motion sensing, a calibration technique has also been developed. Phantom simulations revealed that the motion monitoring system with prediction capability can minimize phase-introduced errors and allow more conformal treatment fields. Accurate calibrations of the radiographic imaging system and the motion detection system can significantly improve the systematic uncertainties.