gebhart/patrepeval huggingface dataset:
Indentation of a rigid sphere into an elastic substrate with surface tension and adhesion (2015)

The surface tension of compliant materials such as gels provides resistance to deformation in addition to and sometimes surpassing that owing to elasticity. This paper studies how surface tension changes the contact mechanics of a small hard sphere indenting a soft elastic substrate. Previous studies have examined the special case where the external load is zero, so contact is driven by adhesion alone. Here, we tackle the much more complicated problem where, in addition to adhesion, deformation is driven by an indentation force. We present an exact solution based on small strain theory. The relation between indentation force (displacement) and contact radius is found to depend on a single dimensionless parameter: <i>ω</i>=<i>σ</i>(<i>μR</i>)<sup>-2/3</sup>((9<i>π</i>/4)<i>W</i><sub>ad</sub>)<sup>-1/3</sup>, where <i>σ</i> and <i>μ</i> are the surface tension and shear modulus of the substrate, <i>R</i> is the sphere radius and <i>W</i><sub>ad</sub> is the interfacial work of adhesion. Our theory reduces to the Johnson-Kendall-Roberts (JKR) theory and Young-Dupre equation in the limits of small and large <i>ω</i>, respectively, and compares well with existing experimental data. Our results show that, although surface tension can significantly affect the indentation force, the magnitude of the pull-off load in the partial wetting liquid-like limit is reduced only by one-third compared with the JKR limit and the pull-off behaviour is completely determined by <i>ω</i>.
Supplementary Figures 1-3 from Host-Derived Angiopoietin-2 Affects Early Stages of Tumor Development and Vessel Maturation but Is Dispensable for Later Stages of Tumor Growth (2023)

Supplementary Figures 1-3 from Host-Derived Angiopoietin-2 Affects Early Stages of Tumor Development and Vessel Maturation but Is Dispensable for Later Stages of Tumor Growth
Self-Stabilized Oligonucleotides as Novel Antisense Agents (2017)

Antisense oligonucleotides and their several modified analogs have been studied in order to regulate the expression of various genes in vitro as well as in vivo. This chapter discusses oligonucleotides called &quot;self-stabilized oligonucleotides&quot; in which oligonucleotides have been stabilized towards nucleases by structural modification rather than the chemical modification. Self-stabilized oligonucleotides have increased nuclease resistance, hybridize selectively with target nucleic acid, and are taken up by cells effectively. The hairpin loop domain of self-stabilized oligonucleotide does not interfere in its selectivity and affinity for the target nucleic acid. Self-stabilized oligonucleotides should be more selective for their targets over their linear counterparts. The approach to self-stabilized oligonucleotide described here is applicable to both oligodeoxyribonucleotides and to oligoribonucleotides containing phosphorodiester, phosphorothioate, or other nuclease-susceptible internucleotide linkages. The antiviral activity of self-stabilized oligonucleotide phosphorothioates has been studied against three viruses, human immunodeficiency virus-1, influenza virus type A, and herpes simplex virus type 1, in tissue culture assays.
Structural CNT Composites Part II: Assessment of CNT Yarns as Reinforcement for Composite Overwrapped Pressure Vessels (2015)

Carbon nanotubes (CNTs) are one-dimensional nanomaterials with outstanding electrical and thermal conductivities and mechanical properties. This combination of properties offers routes to enable lightweight structural aerospace components. Recent advances in the manufacturing of CNTs have made bulk forms such as yarns, tapes and sheets available in commercial quantities to permit the evaluation of these materials for aerospace use, where the superior tensile properties of CNT composites can be exploited in tension dominated applications such as composite overwrapped pressure vessels (COPVs). To investigate their utility in this application, aluminum rings were overwrapped with thermoset/CNT yarn composite and their mechanical properties measured. CNT composite overwrap characteristics such as processing method, CNT/resin ratio, and applied tension during CNT yarn winding were varied to determine their effects on the mechanical performance of the CNT composite overwrapped Al rings (CCOARs). Mechanical properties of the CCOARs were measured under static and cyclic loads at room, elevated, and cryogenic temperatures to evaluate their mechanical performance relative to bare Al rings. At room temperature, the breaking load of CCOARs with a 10.8% additional weight due to the CNT yarn/thermoset overwrap increased by over 200% compared to the bare Al ring. The quality of the wound CNT composites was also investigated using x-ray computed tomography.
Silicon‐Directed Nazarov Reactions II. Preparation and Cyclization of β‐Silyl‐substituted Divinyl Ketones (1983)

Abstract Two general methods for the preparation of β‐silyl‐substituted divinyl ketones have been developed starting from either α, β‐unsaturated aldehydes or simple ketones. Anhydrous FeCl 3 induces the cyclization to cyclopentenones under mild conditions and in good yields with predictable and complete control over the position of the double bond in the five‐membered ring. The observed effects of substituents on rate can be explained by a rate‐determining cationic electrocyclization. Silyl substitution has been shown to retard the reaction.
Semi-Supervised Automated Layer Identification of X-ray Tomography Imaged PCBs (2020)

Reverse engineering (RE) for printed circuit boards (PCB) can be achieved through X-ray Computed Tomography (CT) in a non-destructively yet predominantly manual process. For practical RE to be possible in applications such as obsolescence replacement and hardware assurance, it is important that this process be as automated and fast as possible. This paper introduces a framework to identify which slices of an X-ray CT 3-D PCB stack belong to what layer on a physical PCB in an automated and generalizable fashion for any X-rayed PCB. To the best of our knowledge, this is the first method for identifying the correspondence between an X-ray CT slice and layers of a PCB using reference design information, demonstrated on a 6 layered PCB. First, a spatial pyramid bag-of-visual-words technique is leveraged to enable a semi-supervised approach where the user has either digital or X-ray layout information available for heterogeneous image comparison between X-ray CT image slices. Second, a weighting scheme based on entropy of an image region is proposed. Our results show near perfect quantitative and qualitative layer identification. The completion of this step facilitates improved performance in later RE stages, such as feature extraction or analysis of an X-rayed PCB.
Syntheses of Novel Polynorbornene Derivatives via Ring Opening Metathesis Polymerization (2006)

Abstract Ring opening metathesis is an important class of controlled polymerization techniques. Synthesis of novel polynorbornene derivatives with functional groups designed for application in crosslikable and self assembling materials, and the polymerizations via ROMP and/or free radical polymerization are introduced. Novel monomers and/or macroinitiators for combination of two polymerization techniques are useful for controlling molecular architecture. The sequence of using controlled polymerization techniques affects the molecular structure and the properties of resulting polymers.
Effects of Longwall Mining Subsidence on Ground Water Levels Within a Watershed Hydraulically Isolated from Mine Drainage (1994)

Surface and ground water resources are effectively preserved from depletion by underground mine drainage if impervious deposits of sufficient thickness and extent that underlie the aquifer avoid fracturing and undergo only plastic deformation resulted from the strata flexure. This does not mean, however, that these waters are not subjected to the effects of mining disturbance. Differential vertical settlement of the mine overburden and the ground surface can significantly affect flow pattern and water retention within a watershed area. This is evident, for example, in the areas of multi seam coal mining where the longwall method is used. The effects of this type of mining on water level were tested in a selected watershed where shallow water bearing deposits were entirely isolated from underground mine pumpage. Results of more than 7 years of field investigations were compared with data collected from other coal mining areas of various hydrogeological conditions. The study revealed a variety of water table responses on the postmining subsidence. Basically, changes of water table height in a given site above the point located at the top of aquifer base depend mainly on alteration of that point position against the local drainage base in the hierarchic structure of flow system. The relationship between the magnitude of ground subsidence and water level decline varies within the area of the subsidence trough, within the watershed, and among various watersheds of different hydrogeologic conditions. Except for the situation of hydrostatic flow conditions, lowering of water table elevation in response to the settlement of aquifer base was observed.
Military Blast Exposure and Chronic Neurodegeneration: Summary of Working Groups and Expert Panel Findings and Recommendations (2017)

The potential relationship between chronic traumatic encephalopathy (CTE) and head injuries such as blast-related traumatic brain injury (TBI) is an important area of study, particularly for military and contact sports populations, yet little is known about this relationship. To address this topic, the Department of Defense (DoD) Blast Injury Research Program Coordinating Office organized the 2015 International State-of-the-Science Meeting, which brought together subject matter experts from the DoD, other federal agencies, academia, industry, foreign allies, and the sports community. Over the course of the meeting, this community of experts reached a consensus regarding the current body of knowledge and the future of the field. The overarching finding was that there is insufficient existing scientific evidence to link blast-related TBI with CTE. The meeting's Expert Panel also agreed on 13 additional findings describing research and knowledge gaps, clinical gaps, and research opportunities that, if addressed with focused effort, would further the understanding of the relationship between blast-related TBI and CTE. To this end, the Expert Panel also developed six recommendations for advancing research, each with short- and long-term goals. Among the six recommendations, the Expert Panel identified the first four as highest priority for addressing pressing research needs. These four high-priority recommendations include, in order of priority: (1) more collection and study of clinical neuropathology samples, (2) standardization of clinical diagnostic criteria, (3) development of clinically appropriate and standardized animal models, and (4) development of noninvasive serial assessment strategies (i.e., imaging or biospecimen biomarkers).
Thermally activated carrier transfer among CdTe∕ZnTe self-organized quantum dots (2006)

Carrier transfer among CdTe∕ZnTe self-organized quantum dots (QDs) was studied using time-resolved photoluminescence (PL) measurements. The authors have confirmed that carriers in the high energy ground states of small QDs transfer to the lower-energy ground states of larger QDs even at 10K. The energy dependence of PL decay time changes uniquely with increasing temperature. They have found that the change in the energy dependence of PL decay time can be explained by thermally activated carrier transfer.
Auto-rectification of user photos (2014)

The image auto rectification project at Google aims to create a pleasanter version of user photos by correcting the small, involuntary camera rotations (roll / pitch/ yaw) that often occur in non-professional photographs. Our system takes the image closer to the fronto-parallel view by performing an affine rectification on the image that restores parallelism of lines that are parallel in the fronto-parallel image view. This partially corrects perspective distortions, but falls short of full metric rectification which also restores angles between lines. On the other hand the 2D homography for our rectification can be computed from only two (as opposed to three) estimated vanishing points, allowing us to fire upon many more images. A new RANSAC based approach to vanishing point estimation has been developed. The main strength of our vanishing point detector is that it is line-less, thereby avoiding the hard, binary (line/no-line) upstream decisions that cause traditional algorithm to ignore much supporting evidence and/or admit noisy evidence for vanishing points. A robust RANSAC based technique for detecting horizon lines in an image is also proposed for analyzing correctness of the estimated rectification. We post-multiply our affine rectification homography with a 2D rotation which aligns the closer vanishing point with the image Y axis.
Focused Shock Drilling Exploratory Research Program. Technical progress report, March 1-September 30, 1985 (1985)

This is the first technical progress report for the Focused Shock Drilling Exploratory Research Program. The Program objectives are to determine the feasibility of high energy steerable focused shock drilling technology. We are well into Task 1 of the Program Plan. The objective of Task 1 was to measure the spark impedance for the five line drill, to test electrode designs for the bit, and to test materials for the erodable face drill bit. We have decided to use a different pulse power machine instead of a single water line for measuring spark impedance and testing electrode designs and have combined the latter part of Task 2, and the initial part of Task 3 into Task 1. In the initial phases of this Program we determined that there were several areas of technology that needed further study before we were ready to build a hundred kilojoule focused shock machine. As described in the proposal, the purpose of Task 1 and the first part of Task 3 was to measure physical properties of the spark impedance in order to be able to correctly design the big machine. We also needed to conduct a study of various pulse power systems to determinemore » which system would be optimal for the focused shock drill. (In the proposal we had proposed using a water line for conducting the experiments, but in the early stages of the contract, we realized that water line may not represent the optimum approach for either laboratory experiments or for an actual down hole machine.« less
A study of frequency response in silicon heterojunction bipolar transistors with amorphous silicon emitters (1996)

A detailed physical model of amorphous silicon (a-Si:H) is incorporated into a two-dimensional device simulator to examine the frequency response limits of silicon heterojunction bipolar transistors (HBT's) with a-Si:H emitters. The cutoff frequency is severely limited by the transit time in the emitter space charge region, due to the low electron drift mobility in a-Si:H, to 98 MHz which compares poorly with the 37 GHz obtained for a silicon homojunction bipolar transistor with the same device structure. The effects of the amorphous heteroemitter material parameters (doping, electron drift mobility, defect density and interface state density) on frequency response are then examined to find the requirements for an amorphous heteroemitter material such that the HBT has better frequency response than the equivalent homojunction bipolar transistor, We find that an electron drift mobility of at least 100 cm/sup 2/ V/sup -1/ s/sup -1/ is required in the amorphous heteroemitter and at a heteroemitter drift mobility of 350 cm/sup 2/ V/sup -1/ s/sup -1/ and heteroemitter doping of 5/spl times/10/sup 17/ cm/sup -3/, a maximum cutoff frequency of 52 GHz can be expected.
Sequence and Stereoselectivity of the C1-Symmetric Metallocene Me2Si(1-(4,7-Me2Ind))(9-Flu)ZrCl2 (2003)

The homo- and copolymerization behaviors of two C1-symmetric metallocenes Me2Si(Ind)(9-Flu)ZrCl2 (2) and Me2Si(1-(4,7-Me2Ind))(9-Flu)ZrCl2 (3) in the presence of methylaluminoxane (MAO) are compared. In liquid propylene at 0 °C, metallocene 2 yields a predominantly isotactic polypropylene of low tacticity ([mmmm] = 27%) where metallocene 3 produces syndiotactic polypropylene (74% [rrrr]). The stereoselectivity of metallocene 3 depends on monomer concentration: the percentage of syndiotactic pentads [rrrr] in polymers derived from 3 increases with increasing monomer concentration. Copolymerization of ethylene and propylene with metallocenes 2 and 3 yields highly alternating but atactic ethylene−propylene copolymers.
Using head movement to recognize activity (2002)

This paper presents a methodology for automatically identifying human actions in either the frontal or the lateral view. By tracking the movement of the head of the subject over successive frames of a monocular grayscale image sequence, we recognize 12 different actions. The head is segmented automatically in each frame, and the feature vectors extracted. Input sequences captured from a fixed CCD camera are matched against stored models of actions. The system uses the nearest neighbor classifier to identify the test action.
Topogivity: A Machine-Learned Chemical Rule for Discovering Topological Materials (2022)

Topological materials present unconventional electronic properties that make them attractive for both basic science and next-generation technological applications. The majority of currently known topological materials have been discovered using methods that involve symmetry-based analysis of the quantum wavefunction. Here we use machine learning to develop a simple-to-use heuristic chemical rule that diagnoses with a high accuracy whether a material is topological using only its chemical formula. This heuristic rule is based on a notion that we term topogivity, a machine-learned numerical value for each element that loosely captures its tendency to form topological materials. We next implement a high-throughput procedure for discovering topological materials based on the heuristic topogivity-rule prediction followed by ab initio validation. This way, we discover new topological materials that are not diagnosable using symmetry indicators, including several that may be promising for experimental observation.
Prediction of OLED Temperature Distribution Based on Neural Network (2021)

Abstract In recent years, the market share of OLED screens has increased year by year. Compared with traditional LCD screens, the advantages of OLED screens with bright colors and lower power consumption are attributed to the fact that LCD needs a backlight LED as the light source, and the pixels of the OLED screen emit light by themselves, so the power consumption of OLED is reduced and the thickness becomes thinner. In addition to the above reasons, OLED has a special advantage, that is, OLED can be bent, so the use of OLED screens is becoming more and more popular, and has even exceeded LCD screens usage rate. Although OLED has many advantages, it still has some disadvantages that need to be improved. OLED has a short lifetime. After a period of use, the luminance of the OLED will degrade, and the luminance degradation experienced by the different region of OLED screen is different, called differential aging, so it will cause burn-in. There have been some studies on OLED luminance degradation, including research on OLED luminance degradation under different temperature conditions, but they have not discussed the effects of temperature in different areas of a panel. Therefore, this paper will discuss the temperature prediction for different regions of an OLED panel. The temperature prediction of the OLED panel is based on the four temperature sensors installed at the rear of the OLED panel and the picture displayed on the panel at the time. The prediction method is neural network that uses pre-collected data for model training. After the training is completed, the temperature distribution of the OLED panel is predicted based on the four temperature sensors and displayed pictures. The prediction error method uses mean square error, and the error value obtained is less than 0.2°C.
Investigation of implantation damage recovery using microwave system for defect-less p-n junction (2014)

Advanced junction technology aiming at defect-less p-n junctions has been studied for the integration of ultimately scaled logic CMOS and non-digital functionalities. It is featured by low-temperature microwave annealing (MWA). We demonstrate that MWA effectively repairs ion-implantation damage without the excessive dopant diffusion in CMOS. This technology is promising for implementing high-performance logic CMOS and highly-functional non-digital components on one chip.
Multifractal radiographic analysis of osteoporosis (1994)

An important complication of osteoporosis is fracture. Alteration in bone structure, as well as decreased bone mass, contribute to the tendency to fracture in osteoporosis. Current methods that measure bone mass alone show substantial overlap of the measurements of osteoporotic patients who fracture with those that do not. Our aim is to develop noninvasive methods of evaluating bone structure on plain film radiographs to better predict fracture risk in osteoporosis. Regions of interest (ROIs) were selected from digitized lateral lumbar spine radiographs of 43 patients being seen in an osteoporosis clinic. The fractal dimension of these ROIs was estimated using a surface area method. The ability of fractal dimension to distinguish between cases that had fracture elsewhere in the spine from those that did not, was evaluated using receiver operating characteristic (ROC) analysis. These results were compared with ROC analysis for these same patients using bone mineral density (BMD) measurements (bone mass). Significantly larger Az (area under ROC curve) values were obtained using fractal dimension (0.87) than from using BMD (0.58), indicating a better test performance using fractal dimension. Therefore, computerized radiographic methods to evaluate bone structure, such as fractal analysis, may be helpful in better determining fracture risk in osteoporosis.
ChemInform Abstract: Catalytic Asymmetric Hydrogenation of Imines with a Chiral Titanocene Catalyst: Kinetic and Mechanistic Investigations. (1995)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Epidemiology, outcomes, and mortality predictors of invasive mold infections among transplant recipients: a 10‐year, single‐center experience (2013)

During the era of culture-based diagnostics, observed rates of IMI were low among all transplants except lung transplant recipients, with relatively higher mortality rates. Diagnostic aggressiveness and host variables impact the reported incidence and outcome of IMI and likely account for institutional variability in multicenter studies. Definitions to standardize diagnoses among SOT recipients are needed.
Ventricular Tachycardia Ablation in the Elderly (2017)

VT ablation in the elderly is feasible and reasonably safe with a modestly higher in-hospital and 1-year mortality, with similar rates of VT recurrence at 1 year compared with younger patients. Successful VT ablation, that is, lack of VT recurrence, is strongly associated with improved survival even in this elderly subgroup.