gebhart/patrepeval huggingface dataset:
Refractive scintillation in the interstellar medium (1987)

The slow variation in the apparent intensity of pulsars on time scales of days to months was recently shown to be due to a large-scale component of interstellar scintillation (Rickett, Coles, and Bourgois). These variations are greater than one would expect if the turbulence spectrum were a simple Kolmogorov power law. It is shown that this large-scale component can be greatly enhanced when the turbulence spectrum has a limiting "inner scale" of the order of 10<SUP>9</SUP>m. The authors present a solution for the covariance of refractive scintillation of an extended source in an extended medium. The results show that refractive scintillations are also responsible for slow variations in "low-frequency variables".
GaAs epitaxy on (001) Si: below 1×106 cm-2 dislocation density with 2.4 pm buffer thickness (2020)

We report a record-low threading dislocation density of 9.3 x10 5 cm -2 in GaAs thin films directly grown on (001) Si substrates. The total buffer thickness (2.4 pm) is only two thirds of the state-of-art reported value.
A &lt;i&gt;j&lt;/i&gt;-Lanes Tree Hashing Mode and &lt;i&gt;j&lt;/i&gt;-Lanes SHA-256 (2013)

j-lanes hashing is a tree mode that splits an input message to j slices, computes j independent digests of each slice, and outputs the hash value of their concatenation. We demonstrate the performance advantage of j-lanes hashing on SIMD architectures, by coding a 4-lanes-SHA-256 implementation and measuring its performance on the latest 3rd Generation IntelR CoreTM. For messages whose lengths range from 2 KB to 132 KB, we show that the 4-lanes SHA-256 is between 1.5 to 1.97 times faster than the fastest publicly available implementation that we are aware of, and between ~2 to ~2.5 times faster than the OpenSSL 1.0.1c implementation. For long messages, there is no significant performance difference between different choices of j. We show that the 4-lanes SHA-256 is faster than the two SHA3 finalists (BLAKE and Keccak) that have a published tree mode implementation. Finally, we explain why j-lanes hashing will be faster on the coming AVX2 architecture that facilitates using 256 bits registers. These results suggest that standardizing a tree mode for hash functions (SHA-256 in particular) could be useful for performance hungry applications.
Laser Flash Photolysis Study of Alkylhalocarbenes Generated from Non-Nitrogenous Precursors (1998)

Previously we have studied the photochemistry of alkylchlorodiazirines using laser flash photolysis methods and the pyridine ylide technique (White et al. J. Org. Chem. 1992, 17, 2841). The yield of trappable carbene was found to be a sensitive function of the alkylcarbene structure. This was attributed to ring opening of the diazirine to form a biradical which could suffer rearrangement, in addition to fragmentation to a carbene. It was also possible to explain the data in terms of a carbene−pyridine complex which can either rearrange or collapse to an ylide. In this work, alkylchlorocarbenes are generated from phenanthridenes. The results do not rule out the intermediacy of a carbene−pyridine complex; however, if this species is formed, it does not rearrange to chloroalkene in competition with collapse to form an ylide. This study reduces the urgency with which to postulate carbene−olefin complexes (Tomioka et al. J. Am. Chem. Soc. 1984, 106, 454).
Soil Fertility and its Relationship to Soil Mineralogy of some Areas in Southwest Sinai, Egypt (2021)

Soil minerals represent an important component of its system, andstudy of their role in soil fertility is essential for better soil managementand consequently high productivity. The aim of this research is to study the influenceof soil minerals on some soil fertility attributes such as clay percentage, OM and CEC. Physical and chemical properties of clay minerals affect soil fertility by controlling nutrient availability and supplies, through the stabilization and sequestration of soil organic matter. Clay minerals also affect soil physical properties through microaggregate formation and controlling soil microbial population and activity. The soils of the study area had a coarse texture with low water retention and high permeability. The clay content is very low. Quartz grains are one of the most common detritus minerals present in different percentages. It was derived from granite and sandstone as parent materials in the study area. Most quartz contains extremely low concentrations of plant nutrient elements other than Si. Although quartz is highly resistant to weathering, silica is slightly soluble at the common pH values of soils.Feldspars are alkali aluminosilicates and are, by far, the most abundant igneous rock forming minerals. Calcite is a calcium carbonate mineral, which was formed in the study area form the breakdown of the carbonate rocks e.g. limestone and dolomite. The low soil-CEC and low organic matter are the main fertility constraints of these soils. Therefore, organic matter application is recommended to improve CEC, carbon content, and nutrient availability.
Modeling, Design, and Verification for the Analog Front-End of a MEMS-Based Parallel Scanning-Probe Storage Device (2007)

We present an integrated analog front-end (AFE) for the read-channel of a parallel scanning-probe storage device. The read/write element is based on an array of microfabricated silicon cantilevers equipped with heating elements to form nanometer-sized indentations in a polymer surface using integral atomic-force microscope (AFM) tips. An accurate cantilever model based on the combination of a thermal/electrical lumped-element model and a behavioral model of the electrostatic/mechanical part are introduced. The behavioral model of the electrostatic/mechanical part is automatically generated from a full finite-element model (FEM). The model is completely implemented in Verilog-A and was used to co-develop the integrated analog front-end circuitry together with the read/write cantilever. The cantilever model and the analog front-end were simulated together and the results were experimentally verified. The approach chosen is well suited for system-level simulation and verification/extraction in a design environment based on standard EDA tools.
Performance of superconducting microwave devices passivated with dielectric materials (1997)

We present a set of experiments which show that three dielectric processing variables in particular affect the performance of superconducting microwave devices: processing time and temperature, moisture content of the dielectric material, and surface interactions with the high temperature superconductor (HTS). The changes in microwave performance of a straight-line microstrip resonator before and after passivation were quantified by measurements of the loaded and unloaded quality factors for each resonator. Dielectric materials of varying moisture content were used. The dielectrics were processed at different times and temperatures. This study shows that the degradation of the microwave devices can be minimized by choosing dielectrics which (i) have a low moisture content, (ii) interact as little as possible with the HTS surface, and (iii) can be rapidly processed at relatively low temperatures.
Effects of Laminate Architecture on Fracture Resistance of Sponge Biosilica: Lessons from Nature (2008)

Abstract Hexactinellid sponges are known for their ability to synthesize unusually long and highly flexible fibrous spicules, which serve as the building blocks of their skeletal systems. The spicules consist of a central core of monolithic hydrated silica, surrounded by alternating layers of hydrated silica and proteinaceous material. The principal objective of the present study is to ascertain the role of the latter laminate architecture in the material's resistance to both crack initiation and subsequent crack growth. This has been accomplished through indentation testing on the giant anchor spicule of Monorhaphis chuni , both in the laminated region and in the monolithic core, along with a theoretical analysis of deformation and cracking at indents. The latter suggests that the threshold load for crack initiation is proportional to K c 4 / E 2 H where K c is fracture toughness, E is Young's modulus, and H is hardness. Two key experimental results emerge. First, the load required to form well‐defined radial cracks from a sharp indent in the laminated region is two orders of magnitude greater than that for the monolithic material. Secondly, its fracture toughness is about 2.5 times that of the monolith, whereas the modulus and hardness are about 20% lower. Combining the latter property values with the theoretical analysis, the predicted increase in the threshold load is a factor of about 80, broadly consistent with the experimental measurements.
Abstract 5447: A novel inhibitor of DNA methylation (2010)

Abstract We previously reported the discovery of XB05, a synthetic small molecule with antiproliferative activity. XB05 was found to be a strong inhibitor of DNMT1 activity in cell-free and cell-based assays. However, screening in the NCI 60 tumor cell lines and analysis using COMPARE indicated a novel mechanism of action for XB05, different from standard demethylating agents such as 5-azacytidine (azaC) and decitabine. Here, we report on new research to further characterize XB05 activity. We have examined the effects of XB05 on clonogenicity, promoter methylation, gene expression, and DNMT1 protein. XB05 was found to inhibit colony formation of HCT116 colon carcinoma cells in a dose-dependent manner with a sub-micromolar IC50. Western blots of nuclear extracts from HCT116 cells treated for 72 h with 100 nM XB05 or 10 µM azaC (as positive control) showed greatly decreased levels of DNMT1, suggesting that binding to XB05 can induce degradation of DNMT1 (previous research indicates direct drug-enzyme binding). Analysis of CDKN2A promoter methylation by bisulfite modification and sequencing demonstrated heavy methylation in untreated HCT116 cells. This was reversed by treatment of with 100 nM XB05 or 10 µM azaC, resulting in re-expression of the gene (which encodes tumor suppressor, p16), as shown by qRT-PCR. Experiments to assess promoter methylation using multiplex arrays and to examine gene expression changes using DNA microarrays were recently completed and data analysis is ongoing. To evaluate in vivo activity, we treated mice bearing subcutaneous HCT116 xenografts by IP injection of XB05 with multiple doses of up to 10 mg/kg. There was no evidence of toxicity as judged by body weights and gross necropsies. The tumors of mice treated with XB05, although not significantly smaller than in control animals, were characterized by extensive necrosis in the center of the tumor, leading to a “hollow” tumor in the majority (12/20) of mice. No similar necrosis was observed in vehicle-treated or azaC-treated mice, suggesting that this effect is treatment related. Because induced necrosis is seen with vascular disrupting agents, we also examined the effect of XB05 on endothelial cells in an in vitro assay, and observed reproducible inhibition of endothelial tube formation at 400 nM or higher. In summary, our new data confirm that XB05 is a potent inhibitor of DNA methylation in cultured cancer cells, and provide the first evidence of in vivo activity, which may involve effects on the tumor vasculature, as well as the tumor itself. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5447.
Interferenceless coded aperture correlation holography with synthetic point spread holograms (2020)

Lensless, interferenceless coded aperture correlation holography (LI-COACH) is an incoherent computational optical technique for three-dimensional (3D) imaging. In direct imaging, the image of the object is generated by a lens, whereas the LI-COACH is an indirect imaging technique that consists of two steps: one-time point spread hologram (PSH) training and then many times imaging of multiple-point objects. In the one-time training step, a point object moves in the object space along the optical axis. Light emitted from the point is modulated by a quasi-random phase mask, and the PSH library is recorded. In the imaging step, an object is mounted within the axial boundaries of the PSH library, and the object holograms are recorded using the same quasi-random phase masks. The 3D image of the object is reconstructed by the cross correlation of the object holograms with the PSH library. In this study, the entire PSH library is digitally synthesized from a single PSH, recorded at one plane only. The recorded PSH is scaled by magnification factors corresponding to the various axial planes. The reconstruction results from the synthetic PSH library are comparable with those from the recorded PSH library. The proposed approach can reduce the time of the training step in LI-COACH.
Online selection of diverse results (2012)

The phenomenal growth in the volume of easily accessible information via various web-based services has made it essential for service providers to provide users with personalized representative summaries of such information. Further, online commercial services including social networking and micro-blogging websites, e-commerce portals, leisure and entertainment websites, etc. recommend interesting content to users that is simultaneously diverse on many different axes such as topic, geographic specificity, etc. The key algorithmic question in all these applications is the generation of a succinct, representative, and relevant summary from a large stream of data coming from a variety of sources. In this paper, we formally model this optimization problem, identify its key structural characteristics, and use these observations to design an extremely scalable and efficient algorithm. We analyze the algorithm using theoretical techniques to show that it always produces a nearly optimal solution. In addition, we perform large-scale experiments on both real-world and synthetically generated datasets, which confirm that our algorithm performs even better than its analytical guarantees in practice, and also outperforms other candidate algorithms for the problem by a wide margin.
Lærerstuderendes undervisning i modeller og modellering i praktikken – handlinger og udfordringer i et PCK-perspektiv (2021)

I dette casebaserede (N=29) studie har lærerstuderende i kontekst af deres praktik gennemført undervisning om modeller og modellering (M&amp;M) i fagene fysik/kemi og biologi. Undervisningen er dokumenteret vha. lektionsplaner, videoklip og refleksioner. Empirien er analyseret mhp. at identificere typiske træk og udfordringer i de lærerstuderendes tidlige praksis. Cases er samtidig analyseret for tegn på M&amp;M-PCK ud fra en nyudviklet analyseramme. Resultaterne peger på at de studerende har solid metamodelviden, og at de fortrinsvis baserer deres undervisning på formater som de kender fra læreruddannelsen. PCK-analysen indkredser dog samtidig en række udfordringer som har konsekvenser for arbejdet med M&amp;M på læreruddannelsen.
Demonstration of optical microfluidics (2004)

We demonstrate a novel method for the control of small droplets using laser-based heating. Temperature dependent interfacial surface tensions were the primary force used to move droplets. With this approach, ~1.7 &mu;L to 14 pL droplets were moved on a bare, unmodified polystyrene surface, at speeds of up to 3 mm/s. Upon contact, droplets spontaneously fused and rapidly mixed within 33 ms. We performed an optical absorption-based protein assay using horseradish peroxidase and a chromogenic substrate (ABTS), and readily detected as little as ~125 attomoles of reacting enzyme.
A Unique New Humanized Mouse Model for Multiple Myeloma (MM): Opportunities for Studying MM In Its Natural Environment and for Preclinical Testing (2010)

Abstract Abstract 981 Here we report the development of a unique mouse model to study the pathobiology of multiple myeloma (MM) by implementing a technology for creating a natural human bone environment in the immune deficient RAG2γ-/-c-/- mouse. To this end we combined a procedure to culture-expand human BM-derived mesenchymal stromal cells (MSC) that were seeded on biphasic calcium phosphate (BCP) particles and subsequently implanted subcutaneously in RAG2γ-/-c-/- mice. Within 6 weeks this leads to the formation of so-called ossicles that contain substantial amounts of human bone, while the remaining open spaces are filled with mouse hematopoietic cells and blood vessels, creating an environment that strongly resembles the human bone marrow. A striking finding was that this humanized environment in the mouse acts as a 3-D natural “niche” for patient MM (pMM) cells. Intrascaffold injection of pMM cells resulted in engraftment and outgrowth of tumor cells in close contact with the human bone layer in the ossicles. In addition, intracardial injection, revealed that these primary tumor cells were also capable of homing to the implanted artificial BM-niches, while no tumor cells were detected in the mouse BM. The outgrowth of pMM in this model is accompanied by an increase in osteoclast number on the bone surface, indicating the presence of bone resorption, one of the most important clinical sequelae of MM. Interestingly, by gene-marking pMM cells with luciferase and using bioluminescent imaging, we were able to follow myeloma outgrowth in time, and visualize the effect of treatment. Hence, this novel humanized mouse model provides the first opportunity to investigate patient-derived MM plasma cells in their natural environment, which may lead to better insights in the pathogenesis of this disease. Furthermore, it could serve as a model for preclinical testing of new therapeutic approaches for the treatment of MM patients. Disclosures: de Weers: Genmab bv: Employment.
Monitoring of Congenital Adrenal Hyperplasia by Microbore HPLC–Electrospray Ionization Tandem Mass Spectrometry of Dried Blood Spots (2002)

In the present study, we demonstrated that the concentration of fetal DNA within maternal plasma is increased in cases of placenta previa, especially in patients with invasive placenta. We believe that invasion of trophoblasts into uterine muscle in these patients led to increased concentrations of cell-free fetal DNA within maternal plasma. Because the concentration of fetal DNA was high in the plasma of women with invasive placenta, antenatal diagnosis might be achieved through analysis of fetal DNA concentrations within maternal plasma. Placenta previa and a previous history of uterine surgery, including cesarean delivery, are considered risk factors for invasive placenta. In women who have these risk factors, fetal DNA quantification would be especially useful in the detection of invasive placenta.
Energy flow in terrestrial controlled-source electromagnetic geophysics (2019)

Abstract Visualisations of the flow of electromagnetic energy based on the time-averaged Poynting vector have yielded important and sometimes counter-intuitive physical insights in the case of electric circuits containing resistors and inductors. Less well-understood is the flow of electromagnetic energy in spatially contiguous media excited by grounded sources. In geophysics, for example, it is important for readers to recognise how geological structures help shape controlled-source electromagnetic responses. It is demonstrated herein using energy flow visualisations how a resistive layer impeding vertical electric current flow will produce a larger anomalous response to grounded-source excitation at the Earth’s surface than an equivalent conductive layer.
Vertical-cavity surface-emitting laser flip-chip bonding to silicon photonics chip (2015)

We demonstrate the integration of vertical-cavity surface-emitting lasers (VCSELs) with silicon photonics chip using flip-chip bonding technique, with bidirectional vertical-coupled grating coupler for light coupling.
Excess Lipin enzyme activity contributes to TOR1A recessive disease and DYT-TOR1A dystonia (2020)

TOR1A/TorsinA mutations cause two incurable diseases: a recessive congenital syndrome that can be lethal, and a dominantly-inherited childhood-onset dystonia (DYT-TOR1A). TorsinA has been linked to phosphatidic acid lipid metabolism in Drosophila melanogaster. Here we evaluate the role of phosphatidic acid phosphatase (PAP) enzymes in TOR1A diseases using induced pluripotent stem cell-derived neurons from patients, and mouse models of recessive Tor1a disease. We find that Lipin PAP enzyme activity is abnormally elevated in human DYT-TOR1A dystonia patient cells and in the brains of four different Tor1a mouse models. Its severity also correlated with the dosage of Tor1a/TOR1A mutation. We assessed the role of excess Lipin activity in the neurological dysfunction of Tor1a disease mouse models by interbreeding these with Lpin1 knock-out mice. Genetic reduction of Lpin1 improved the survival of recessive Tor1a disease-model mice, alongside suppressing neurodegeneration, motor dysfunction, and nuclear membrane pathology. These data establish that TOR1A disease mutations cause abnormal phosphatidic acid metabolism, and suggest that approaches that suppress Lipin PAP enzyme activity could be therapeutically useful for TOR1A diseases.
Abstract P174: Dynamics of the Renin-Angiotensin-Aldosterone System: Implications of Angiotensin-Peptide Fingerprinting on the Clinical Use and Development of Antihypertensive Drugs (2011)

BACKGROUND: The Renin-Angiotensin-Aldosterone-System (RAAS) is an extensively studied peptide hormone system which is critically involved in the regulation of blood pressure and other important physiologic functions. Angiotensin-(1-10) which is liberated from angiotensinogen by kidney secreted Renin, is sequentially metabolized to different N- and C-terminal truncated fragments with partially described biologic activities. Beside Angiotensin II (Ang-(1-8)), various other angiotensin peptides including Ang-(1-7), Ang-(1-9), Ang-(2-8) and Ang-(3-8) are known to possess physiologic activity while Ang-(1-7) and more recently Ang-(1-9) were described to antagonize pathologic effects of Ang-(1-8) via vasodilation and antifibrotic action respectively. The role of Ang-(1-8) in hypertension converts enzymes participating in Ang-(1-8) generation to favorable targets for antihypertensive drugs. METHODS: Human blood was collected from healthy volunteers followed by ex-vivo incubation at 37°C in the presence of different inhibitors of angiotensin metabolism. Angiotensin concentrations were determined employing a novel sensitive LC-MS/MS based method, which allows the simultaneous quantification of a broad panel of angiotensin peptides in human plasma. RESULTS: The investigation of different angiotensin metabolism modifiers revealed agent specific patterns of angiotensin peptide levels reflecting the specificity of these inhibitors. Spiking experiments allowed the determination of turnover rates for distinct angiotensin conversion reactions surrounded by their physiological matrix. CONCLUSION: The measurement of blood concentrations of angiotensin peptides provides important information about the substrate specificities and activities of enzymes involved in their metabolism. This allows the identification of potential causes for pathologic conditions, facilitating a patient specific therapeutic modulation of the RAAS. The overall assessment of angiotensin peptide concentrations (Angiotensin-Peptide-Fingerprinting) represents a powerful tool to gain a more detailed understanding of blood pressure regulation, enabling the pharmacologic characterization of RAAS modifying agents in use and development.