gebhart/patrepeval huggingface dataset:
Friction stir welded and deep drawn multi-material tailor welded blanks (2019)

Abstract The ever increasing demand for more resource-efficient and safer vehicles in today's automotive industry makes lightweight construction techniques necessary. However, overcoming contradicting requirements arising from lightweight design and safety remains a challenging task. The extent to which lightweight measures can be applied in order to save fuel, heavily depends on the fact that rising safety requirements have to be met by increasing strength of parts. This contradicting demand for parts with high strength and low weight leads to the development of new production technologies. One example, regarding car body components, is the tailor welded blank (TWB) technology. In tailor welded blanks, materials and thicknesses are locally adapted to meet the needed strength and strain properties while keeping the weight as low as possible. While tailor welded blanks consisting of similar materials with different thicknesses are already used in vehicles, the use of TWBs with dissimilar materials, e.g. steel and aluminum, is still in development due to the problems in joining dissimilar materials. Especially when manufacturing parts made of TWBs through joining and subsequent deep drawing, the joint needs to have very good strength properties in order not to fail during forming. One way to overcome these joining difficulties is friction stir welding. In this paper, a methodology is presented to produce multi-material tailor welded blanks with varying thicknesses through friction stir welding (FSW) and deep drawing in a subsequent step. A newly developed FSW joint configuration is used to weld steel sheets in 1 mm thickness to 2 mm thick aluminum sheets. A welding parameter study is conducted to investigate the influence of the process parameters on the joint quality. Tensile and Nakajima tests show that the joint strength, obtained with optimal process parameters, exceeds the strength of the steel base material. Thus, failure occurs in the steel, whereas the joint remains intact. The friction stir welded blanks were furthermore deep drawn. Two different tool approaches were tested to compensate the different sheet thicknesses during the forming process. Using the more suitable approach, blanks were deep drawn with three different punch geometries to show the potential of friction stir welding for the manufacturing of multi-material tailor welded blanks.
Pulsed photothermal radiometry as a method for investigating blood vessel-like structures (2001)

Pulsed photothermal radiometry (PPTR) is known to be suitable for in vivo investigations of tissue optical properties. As a noncontact, nondestructive method it is a very attractive candidate for on-line dosimetry of laser treatments that rely on thermal laser-tissue interaction. In this article, we extend the one-dimensional (1D) analytical formalism that has widely been used to describe PPTR signals to a two-dimensional treatment of a simplified model of a blood vessel. This approach leads to quantitative description of a PPTR signal that, unlike in an 1D treatment, not only shows changes in time, but also varies in space. Using this approach, we are able to gain instructive understanding on how target characteristics of a blood vessel-like structure influence such a spatiotemporal PPTR signal. Likewise, the ability of extracting target features from those measurements is evaluated. Subsequently, we present experimental realization of the idealized model of a blood vessel as used in our theory. Comparison of actual PPTR measurements with theoretical predictions allow vessel localization laterally and in depth. Using our setup, we furthermore demonstrate the influence of flow inside the vessel on the measured signal.
Synthesis and exciton optical activity of D3-cryptophanes (1987)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis and exciton optical activity of D3-cryptophanesJosette Canceill, Andre Collet, Giovanni Gottarelli, and Paolo PalmieriCite this: J. Am. Chem. Soc. 1987, 109, 21, 6454–6464Publication Date (Print):October 1, 1987Publication History Published online1 May 2002Published inissue 1 October 1987https://pubs.acs.org/doi/10.1021/ja00255a035https://doi.org/10.1021/ja00255a035research-articleACS PublicationsRequest reuse permissionsArticle Views506Altmetric-Citations63LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Disintegration of the Top Stent on Zenith Abdominal Aortic Stent-Grafts (2016)

Physicians should be aware of the potential for top stent separation from the Zenith LP stent-graft as a cause of endoleak and migration.
Anatomic Relations Between the Lumbar Pedicle and the Adjacent Neural Structures (1997)

On the basis of this study, improper placement of the pedicle screw medially or caudally in the lumbar spine should be avoided.
Fine-scale transgenic mapping of the MyoD core enhancer: MyoD is regulated by distinct but overlapping mechanisms in myotomal and non-myotomal muscle lineages (1999)

Skeletal muscle lineage determination is regulated by the myogenic regulatory genes, MyoD and Myf-5. Previously, we identified a 258 bp core enhancer element 20 kb 5' of the MyoD gene that regulates MyoD gene activation in mouse embryos. To elucidate the cis control mechanisms that regulate MyoD transcription, we have mutagenized the entire core enhancer using linker-scanner mutagenesis, and have tested the transcriptional activity of enhancer mutants using lacZ reporter gene expression in transgenic mouse embryos. In total, 83 stable transgenic lines representing 17 linker-scanner mutations were analyzed in midgestational mouse embryos. Eight linker-scanner mutations resulted in a partial or complete loss of enhancer activity, demonstrating that MyoD is primarily under positive transcriptional control. Six of these mutations reduced or abolished transgene expression in all skeletal muscle lineages, indicating that activation of MyoD expression in trunk, limb and head musculature is regulated, in part, by shared transcriptional mechanisms. Interestingly, however, two adjacent linker-scanner mutations (LS-14 and LS-15) resulted in a dramatic reduction in transgene expression specifically in myotomes at 11.5 days. At later stages, transgene expression was absent or greatly reduced in myotomally derived muscles including epaxial muscles (deep back muscles) and hypaxial muscles of the body wall (intercostal muscles, abdominal wall musculature). In contrast, head muscles, as well as muscles of the body derived from migrating muscle progenitor cells (e.g. limb, diaphragm), were unaffected by these mutations. In Pax-3-mutant mice, LS-14 and LS-15 transgene expression was eliminated in the body, but was unaffected in the head, yielding an identical expression pattern to the endogenous MyoD gene in mice mutant for both Myf-5 and Pax-3. These data support the hypothesis that LS-14 and LS-15 define the core enhancer targets for Myf-5-dependent activation of MyoD in myotomal muscles.
Optimizing Stiffness of a Novel Parallel-Actuated Robotic Shoulder Exoskeleton for a Desired Task or Workspace (2018)

The purpose of this work is to optimize the stiffness of a novel parallel-actuated robotic exoskeleton designed to offer a large workspace. This is done in an effort to help provide a solution to the issue wearable parallel actuated robots face regarding a tradeoff between stiffness and workspace. Presented in the form of a shoulder exoskeleton, the device demonstrates a new parallel architecture that can be used for wearable hip, ankle and wrist robots as well. The stiffness of the architecture is dependent on the placement of its actuated substructures. Therefore, it is desirable to place these substructures effectively so as to maximize dynamic performance for any application. In this work, an analytical stiffness model of the device is created and validated experimentally. The model is then used, along with a method of bounded nonlinear multi-objective optimization to configure the parallel actuators so as to maximize stiffness for the entire workspace. Furthermore, it is shown how to use the same technique to optimize the device for a particular task, such as lifting in the sagittal plane.
Nanosecond time-resolved dual-comb absorption spectroscopy (2022)

Frequency combs have revolutionized the field of optical spectroscopy, enabling researchers to probe molecular systems with a multitude of accurate and precise optical frequencies. While there have been tremendous strides in direct frequency comb spectroscopy, these approaches have been unable to record high resolution spectra on the nanosecond timescale characteristic of many physiochemical processes. Here we demonstrate a new approach to optical frequency comb generation in which a pair of electro-optic combs is produced in the near-infrared and subsequently transferred with high mutual coherence and efficiency into the mid-infrared within a single optical parametric oscillator. The high power, mutual coherence, and agile repetition rates of these combs as well as the large mid-infrared absorption of many molecular species enable fully resolved spectral transitions to be recorded in timescales as short as 20 ns. We have applied this approach to study the rapid dynamics occurring within a supersonic pulsed jet, however we note that this method is widely applicable to fields such as chemical and quantum physics, atmospheric chemistry, combustion science, and biology.
ROLLOVER, BRAKING, AND DYNAMIC STABILITY-MODIFIED SUSPENSION VEHICLES. FINAL REPORT. VOLUME 1. TECHNICAL REPORT (1990)

A study was performed to investigate the dynamic response properties of modified suspension pickup trucks and utility vehicles in particular open loop steering and braking maneuvers. Three example vehicles were tested, a 1985 Toyota pickup, a 1986 Chevrolet K-20 pickup, and a 1986 Chevrolet S-10 Blazer; in both their OE configurations and with extensive suspension, chassis, and tire modifications using aftermarket components. These modifications tended to increase the cg height, widen the track, decrease braking gain, increase suspension compliance, and possibly lead to greater loads on suspension components. Outriggers were used to prevent rollover, and an automatic vehicle controller was used to input large, repeatable and rapid open loop maneuvers. Each vehicle configuration was tested in 5 maneuvers, including straight line braking, trapezoidal steering, braking in a turn, steady state turning, and sinusoidal steering. Full scale test results are presented to show the effect of vehicle modifications on sublimit and limit performance in these maneuvers.
Neurosteroid Synthesis in Adult Female Rat Hippocampus, Including Androgens and Allopregnanolone (2014)

Female rat hippocampus synthesizes significant amount of estrogens, including progesterone (PROG), estrone and estradiol (E2). Hippocampal level of PROG and E2 are considerably higher than those in plasma. Female hippocampal estrogens play a significant role in the fluctuation of dendritic spine density across the estrous cycle. Here we extend the study to the investigation of female androgens, including testosterone (T) and Dihydrotestosterone (DHT), in the female rat hippocampus, since female androgens had been largely unknown. By combination of mass-spectrometric analysis with HPLC-purification and picolinoyl-derivatization of sex steroids, we determined the accurate concentration of T and DHT in the hippocampus. The levels of T and DHT in female hippocampus at Proestrus were approximately 1.1 nM and 0.6 nM, respectively, suggesting a significant synthesis of T and DHT. The level of plasma T was approx. 0.1 nM, implying almost no contribution of plasma T to hippocampal T. The concentration of hippocampal DHT had a good correlation with that of hippocampal T, suggesting a significant activity of 5-reductase (DHT synthase) in the female. Allopregnanolone level was also determined as a useful indicator of 5-reductase activity. Interestingly mRNA expression level of 5-reductase and androgen receptor (AR) was not significantly different between the different estrous cycle stages, or between female and male. Nevertheless, sex difference existed with respect to the levels of T, DHT and Allo in hippocampus. Although physiological significance of female hippocampal androgens waits further investigations, the female hippocampus produces T or DHT which may be useful to suppress anxiety, for example.
Weight approximations in multi‐attribute decision models (2002)

Abstract The use of surrogate weights based on rankings has been proposed as a method for avoiding difficulties associated with the elicitation of weights in multi‐attribute decision analysis. When the simple multiattribute rating technique using swings (SMARTS) method is being employed it has been suggested that rank order centroid (ROC) weights are the best surrogate weights to use. This study shows that ROC weights are appropriate to use as a substitute for original weights that are constrained to sum to a fixed total (usually 1 or 100) as used in the point allocation method. If, however, the original weights are determined without any initial restrictions, as in the direct rating method, and are then normalized, which is the common procedure in SMARTS analysis, then the ROC weights do not provide the best approximations to the original weights. This paper shows how to obtain rank order distribution (ROD) weights that provide a better approximation than the ROC approach to unrestricted original weights. The paper also shows that, as the number of attributes in a decision problem increases, the ROD weights approximate to the more easily calculated rank sum weights. Copyright © 2003 John Wiley &amp; Sons, Ltd.
Dynamics of critical fluctuations of a macromolecular solution (1975)

The angular and the spectral distribution of scattered light intensity and the hydrodynamic shear viscosity from polystyrene (Mn = 1.96×105, Mw/Mn &amp;lt; 1.02) in cyclohexane were measured at the critical solution concentration above the critical consolute temperature in the one phase region. In comparing the linewidth, correlation length, and shear viscosity data with the modified mode−mode coupling theory of Kawasaki, we note that the magnitude of a ’’scaled linewidth’’ Γ+ (≡6πη*pΓ/kBTK3) as a function of Kξ is a factor of 1.5−3 higher than the single universal curve of Kawasaki and Lo, where η*p, Γ, kB, T, K, and ξ are, respectively, the shear viscosity, the linewidth, the Boltzmann constant, the absolute temperature, the magnitude of the momentum transfer vector, and the correlation length. Since the theory describes only the critical part of the linewidth Γc, we separate the decay rate due to critical fluctuations and the finite molecular size of the polymer. The resultant scaled linewidth Γ* (≡6πη*pΓc/ kBTK3) as a function of Kξ can then be brought down to the universal curve. Our comparison between existing polymer data and theory represents a first attempt to take into account the finite molecular dimension of the system in decay rate of order parameter fluctuations. The data exhibit considerable scatter after the background correction. Consequently, there seems to be a need to consider more carefully the manner in which the backgrounds are subtracted before more crucial comparisons between experiments and theory can be made.
Insights Into Vascular Anomalies, Cancer, and Fibroproliferative Conditions: The Role of Stem Cells and the Renin-Angiotensin System (2022)

Cells exhibiting embryonic stem cell (ESC) characteristics have been demonstrated in vascular anomalies (VAs), cancer, and fibroproliferative conditions, which are commonly managed by plastic surgeons and remain largely unsolved. The efficacy of the mTOR inhibitor sirolimus, and targeted therapies that block the Ras/BRAF/MEK/ERK1/2 and PI3KCA/AKT/mTOR pathways in many types of cancer and VAs, further supports the critical role of ESC-like cells in the pathogenesis of these conditions. ESC-like cells in VAs, cancer, and fibroproliferative conditions express components of the renin-angiotensin system (RAS) - a homeostatic endocrine signaling cascade that regulates cells with ESC characteristics. ESC-like cells are influenced by the Ras/BRAF/MEK/ERK1/2 and PI3KCA/AKT/mTOR pathways, which directly regulate cellular proliferation and stemness, and interact with the RAS at multiple points. Gain-of-function mutations affecting these pathways have been identified in many types of cancer and VAs, that have been treated with targeted therapies with some success. In cancer, the RAS promotes tumor progression, treatment resistance, recurrence, and metastasis. The RAS modulates cellular invasion, migration, proliferation, and angiogenesis. It also indirectly regulates ESC-like cells via its direct influence on the tissue microenvironment and by its interaction with the immune system. <i>In vitro</i> studies show that RAS inhibition suppresses the hallmarks of cancer in different experimental models. Numerous epidemiological studies show a reduced incidence of cancer and improved survival outcomes in patients taking RAS inhibitors, although some studies have shown no such effect. The discovery of ESC-like cells that express RAS components in infantile hemangioma (IH) underscores the paradigm shift in the understanding of its programmed biologic behavior and accelerated involution induced by β-blockers and angiotensin-converting enzyme inhibitors. The findings of SOX18 inhibition by R-propranolol suggests the possibility of targeting ESC-like cells in IH without β-adrenergic blockade, and its associated side effects. This article provides an overview of the current knowledge of ESC-like cells and the RAS in VAs, cancer, and fibroproliferative conditions. It also highlights new lines of research and potential novel therapeutic approaches for these unsolved problems in plastic surgery, by targeting the ESC-like cells through manipulation of the RAS, its bypass loops and converging signaling pathways using existing low-cost, commonly available, and safe oral medications.
Influence of Land Use and Site Characteristics on Invasive Plant Abundance in the Quinebaug Highlands of Southern New England (2004)

Invasive exotic plants have been identified as one of the major threats to ecosystem function and biodiversity. This study examined the distribution and abundance (cover and frequency) of invasive plants in natural habitats of the Quinebaug Highlands forest block (13,760 ha) of northern Connecticut and southern Massachusetts in relation to current and historical land use and site conditions. Multiple regression and GIS analyses were used to identify areas of high infestation and factors most useful in predicting invasions. Celastrus orbiculatus, Rosa multiflora, and Berberis thunbergii were the most frequent invasives. Past land use was the strongest predictor of invasive cover (r2 = 0.219) and richness (r2 = 0.303; p < 0.001 both regressions). Current land development and physical soil characteristics were also strongly correlated. These results add to our understanding of factors promoting plant invasions. Because invasive species control in natural areas is time- and resource-intensive, this information may enhance conservation efforts by increasing efficiency in predicting and managing biological invasions.
A study of Docetaxel-induced effects in MCF-7 cells by means of Raman microspectroscopy (2012)

Chemotherapies feature a low success rate of about 25%, and therefore, the choice of the most effective cytostatic drug for the individual patient and monitoring the efficiency of an ongoing chemotherapy are important steps towards personalized therapy. Thereby, an objective method able to differentiate between treated and untreated cancer cells would be essential. In this study, we provide molecular insights into Docetaxel-induced effects in MCF-7 cells, as a model system for adenocarcinoma, by means of Raman microspectroscopy combined with powerful chemometric methods. The analysis of the Raman data is divided into two steps. In the first part, the morphology of cell organelles, e.g. the cell nucleus has been visualized by analysing the Raman spectra with k-means cluster analysis and artificial neural networks and compared to the histopathologic gold standard method hematoxylin and eosin staining. This comparison showed that Raman microscopy is capable of displaying the cell morphology; however, this is in contrast to hematoxylin and eosin staining label free and can therefore be applied potentially in vivo. Because Docetaxel is a drug acting within the cell nucleus, Raman spectra originating from the cell nucleus region were further investigated in a next step. Thereby we were able to differentiate treated from untreated MCF-7 cells and to quantify the cell-drug response by utilizing linear discriminant analysis models.
Material impulse response estimation from overlapping ultrasound echoes using a compressed sensing technique (2017)

In ultrasound examination of thin multi-layered materials, the received signal is, in both through-transmission and pulse-echo configurations, a superposition of multiple reflections from inside the sample. If the layer thicknesses are small compared to the duration of the emitted ultrasound pulse, the received signal will be a sum of overlapping ultrasound pulses. In such scenarios, estimation of the layer thicknesses is challenging. Previous work has adopted model-based decomposition of the overlapping echoes, or various pulse compression or deconvolution schemes, in order to better reveal the arrival times of each individual echo.
Prediction of maximum P- and S-wave amplitude distributions incorporating frequency- and distance-dependent characteristics of the observed apparent radiation patterns (2016)

Frequency-dependent model of the apparent radiation pattern has been extensively incorporated into engineering and scientific applications for high-frequency seismic waves, but distance-dependent properties have not yet been fully taken into account. We investigated the unified characteristics of frequency and distance dependences in both apparent P- and S-wave radiation patterns during local crustal earthquakes. Observed distortions of the apparent P- and S-wave radiation patterns could be simply modeled by using a function of the normalized hypocentral distance, which is a product of the wave number and hypocentral distance. This behavior suggests that major cause of distortion of the apparent radiation pattern is seismic wave scattering and diffraction within the heterogeneous crust. On the basis of observed normalized hypocentral distance dependency, we proposed a method for prediction of spatial distributions of maximum P- and S-wave amplitudes. Our method incorporating normalized hypocentral distance dependence of the apparent radiation pattern reproduced the observed spatial distributions of maximum P- and S-wave amplitudes over a wide frequency and distance ranges successfully.